Merge pull request #47353 from apelisse/http-cache

Automatic merge from submit-queue

go-client: Use httpcache client for all requests, even though only openapi returns ETags for caching

**What this PR does / why we need it**: Use HTTP ETag for caching Swagger spec download

This also adds a new command-line flag "cachedir" to specify where the cache should keep its file. It defaults to `$HOME/.kube/http-cache`.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: partly #38637

**Special notes for your reviewer**:
Because this adds a bunch of dependencies, and removes a couple of files, I do recommend reading each commit individually.

**Release note**:
```release-note
```

Kubernetes-commit: fc89743dca6b563063b74728c3b28100cf674d9d

vendor/github.com/coreos/etcd/auth/simple_token.go

@@ -37,27 +37,19 @@ var (
 )
 
 type simpleTokenTTLKeeper struct {
-	tokensMu        sync.Mutex
 	tokens          map[string]time.Time
-	stopCh          chan chan struct{}
+	donec           chan struct{}
+	stopc           chan struct{}
 	deleteTokenFunc func(string)
-}
-
-func NewSimpleTokenTTLKeeper(deletefunc func(string)) *simpleTokenTTLKeeper {
-	stk := &simpleTokenTTLKeeper{
-		tokens:          make(map[string]time.Time),
-		stopCh:          make(chan chan struct{}),
-		deleteTokenFunc: deletefunc,
-	}
-	go stk.run()
-	return stk
+	mu              *sync.Mutex
 }
 
 func (tm *simpleTokenTTLKeeper) stop() {
-	waitCh := make(chan struct{})
-	tm.stopCh <- waitCh
-	<-waitCh
-	close(tm.stopCh)
+	select {
+	case tm.stopc <- struct{}{}:
+	case <-tm.donec:
+	}
+	<-tm.donec
 }
 
 func (tm *simpleTokenTTLKeeper) addSimpleToken(token string) {
@@ -76,27 +68,45 @@ func (tm *simpleTokenTTLKeeper) deleteSimpleToken(token string) {
 
 func (tm *simpleTokenTTLKeeper) run() {
 	tokenTicker := time.NewTicker(simpleTokenTTLResolution)
-	defer tokenTicker.Stop()
+	defer func() {
+		tokenTicker.Stop()
+		close(tm.donec)
+	}()
 	for {
 		select {
 		case <-tokenTicker.C:
 			nowtime := time.Now()
-			tm.tokensMu.Lock()
+			tm.mu.Lock()
 			for t, tokenendtime := range tm.tokens {
 				if nowtime.After(tokenendtime) {
 					tm.deleteTokenFunc(t)
 					delete(tm.tokens, t)
 				}
 			}
-			tm.tokensMu.Unlock()
-		case waitCh := <-tm.stopCh:
-			tm.tokens = make(map[string]time.Time)
-			waitCh <- struct{}{}
+			tm.mu.Unlock()
+		case <-tm.stopc:
 			return
 		}
 	}
 }
 
+func (as *authStore) enable() {
+	delf := func(tk string) {
+		if username, ok := as.simpleTokens[tk]; ok {
+			plog.Infof("deleting token %s for user %s", tk, username)
+			delete(as.simpleTokens, tk)
+		}
+	}
+	as.simpleTokenKeeper = &simpleTokenTTLKeeper{
+		tokens:          make(map[string]time.Time),
+		donec:           make(chan struct{}),
+		stopc:           make(chan struct{}),
+		deleteTokenFunc: delf,
+		mu:              &as.simpleTokensMu,
+	}
+	go as.simpleTokenKeeper.run()
+}
+
 func (as *authStore) GenSimpleToken() (string, error) {
 	ret := make([]byte, defaultSimpleTokenLength)
 
@@ -113,9 +123,7 @@ func (as *authStore) GenSimpleToken() (string, error) {
 }
 
 func (as *authStore) assignSimpleTokenToUser(username, token string) {
-	as.simpleTokenKeeper.tokensMu.Lock()
 	as.simpleTokensMu.Lock()
-
 	_, ok := as.simpleTokens[token]
 	if ok {
 		plog.Panicf("token %s is alredy used", token)
@@ -124,14 +132,12 @@ func (as *authStore) assignSimpleTokenToUser(username, token string) {
 	as.simpleTokens[token] = username
 	as.simpleTokenKeeper.addSimpleToken(token)
 	as.simpleTokensMu.Unlock()
-	as.simpleTokenKeeper.tokensMu.Unlock()
 }
 
 func (as *authStore) invalidateUser(username string) {
 	if as.simpleTokenKeeper == nil {
 		return
 	}
-	as.simpleTokenKeeper.tokensMu.Lock()
 	as.simpleTokensMu.Lock()
 	for token, name := range as.simpleTokens {
 		if strings.Compare(name, username) == 0 {
@@ -140,5 +146,4 @@ func (as *authStore) invalidateUser(username string) {
 		}
 	}
 	as.simpleTokensMu.Unlock()
-	as.simpleTokenKeeper.tokensMu.Unlock()
 }

vendor/github.com/coreos/etcd/auth/store.go

@@ -215,8 +215,7 @@ func (as *authStore) AuthEnable() error {
 	tx.UnsafePut(authBucketName, enableFlagKey, authEnabled)
 
 	as.enabled = true
-
-	as.simpleTokenKeeper = NewSimpleTokenTTLKeeper(newDeleterFunc(as))
+	as.enable()
 
 	as.rangePermCache = make(map[string]*unifiedRangePermissions)
 
@@ -244,11 +243,12 @@ func (as *authStore) AuthDisable() {
 	as.enabled = false
 
 	as.simpleTokensMu.Lock()
+	tk := as.simpleTokenKeeper
+	as.simpleTokenKeeper = nil
 	as.simpleTokens = make(map[string]string) // invalidate all tokens
 	as.simpleTokensMu.Unlock()
-	if as.simpleTokenKeeper != nil {
-		as.simpleTokenKeeper.stop()
-		as.simpleTokenKeeper = nil
+	if tk != nil {
+		tk.stop()
 	}
 
 	plog.Noticef("Authentication disabled")
@@ -647,14 +647,12 @@ func (as *authStore) RoleAdd(r *pb.AuthRoleAddRequest) (*pb.AuthRoleAddResponse,
 
 func (as *authStore) AuthInfoFromToken(token string) (*AuthInfo, bool) {
 	// same as '(t *tokenSimple) info' in v3.2+
-	as.simpleTokenKeeper.tokensMu.Lock()
 	as.simpleTokensMu.Lock()
 	username, ok := as.simpleTokens[token]
-	if ok {
+	if ok && as.simpleTokenKeeper != nil {
 		as.simpleTokenKeeper.resetSimpleToken(token)
 	}
 	as.simpleTokensMu.Unlock()
-	as.simpleTokenKeeper.tokensMu.Unlock()
 	return &AuthInfo{Username: username, Revision: as.revision}, ok
 }
 
@@ -914,7 +912,7 @@ func NewAuthStore(be backend.Backend, indexWaiter func(uint64) <-chan struct{})
 	}
 
 	if enabled {
-		as.simpleTokenKeeper = NewSimpleTokenTTLKeeper(newDeleterFunc(as))
+		as.enable()
 	}
 
 	if as.revision == 0 {

vendor/github.com/coreos/etcd/clientv3/client.go

@@ -282,8 +282,16 @@ func (c *Client) dial(endpoint string, dopts ...grpc.DialOption) (*grpc.ClientCo
 			tokenMu: &sync.RWMutex{},
 		}
 
-		err := c.getToken(context.TODO())
-		if err != nil {
+		ctx := c.ctx
+		if c.cfg.DialTimeout > 0 {
+			cctx, cancel := context.WithTimeout(ctx, c.cfg.DialTimeout)
+			defer cancel()
+			ctx = cctx
+		}
+		if err := c.getToken(ctx); err != nil {
+			if err == ctx.Err() && ctx.Err() != c.ctx.Err() {
+				err = grpc.ErrClientConnTimeout
+			}
 			return nil, err
 		}
 
@@ -335,6 +343,8 @@ func newClient(cfg *Config) (*Client, error) {
 	client.balancer = newSimpleBalancer(cfg.Endpoints)
 	conn, err := client.dial(cfg.Endpoints[0], grpc.WithBalancer(client.balancer))
 	if err != nil {
+		client.cancel()
+		client.balancer.Close()
 		return nil, err
 	}
 	client.conn = conn
@@ -353,6 +363,7 @@ func newClient(cfg *Config) (*Client, error) {
 		}
 		if !hasConn {
 			client.cancel()
+			client.balancer.Close()
 			conn.Close()
 			return nil, grpc.ErrClientConnTimeout
 		}

vendor/github.com/coreos/etcd/clientv3/watch.go

@@ -616,10 +616,24 @@ func (w *watchGrpcStream) serveSubstream(ws *watcherStream, resumec chan struct{
 					if ws.initReq.createdNotify {
 						ws.outc <- *wr
 					}
+					// once the watch channel is returned, a current revision
+					// watch must resume at the store revision. This is necessary
+					// for the following case to work as expected:
+					//	wch := m1.Watch("a")
+					//	m2.Put("a", "b")
+					//	<-wch
+					// If the revision is only bound on the first observed event,
+					// if wch is disconnected before the Put is issued, then reconnects
+					// after it is committed, it'll miss the Put.
+					if ws.initReq.rev == 0 {
+						nextRev = wr.Header.Revision
+					}
 				}
+			} else {
+				// current progress of watch; <= store revision
+				nextRev = wr.Header.Revision
 			}
 
-			nextRev = wr.Header.Revision
 			if len(wr.Events) > 0 {
 				nextRev = wr.Events[len(wr.Events)-1].Kv.ModRevision + 1
 			}

vendor/github.com/coreos/etcd/etcdserver/api/v3rpc/maintenance.go

@@ -185,9 +185,5 @@ func (ams *authMaintenanceServer) Hash(ctx context.Context, r *pb.HashRequest) (
 }
 
 func (ams *authMaintenanceServer) Status(ctx context.Context, ar *pb.StatusRequest) (*pb.StatusResponse, error) {
-	if err := ams.isAuthenticated(ctx); err != nil {
-		return nil, err
-	}
-
 	return ams.maintenanceServer.Status(ctx, ar)
 }

vendor/github.com/coreos/etcd/etcdserver/apply.go

@@ -520,15 +520,14 @@ func (a *applierV3backend) LeaseGrant(lc *pb.LeaseGrantRequest) (*pb.LeaseGrantR
 	if err == nil {
 		resp.ID = int64(l.ID)
 		resp.TTL = l.TTL()
-		resp.Header = &pb.ResponseHeader{Revision: a.s.KV().Rev()}
+		resp.Header = newHeader(a.s)
 	}
-
 	return resp, err
 }
 
 func (a *applierV3backend) LeaseRevoke(lc *pb.LeaseRevokeRequest) (*pb.LeaseRevokeResponse, error) {
 	err := a.s.lessor.Revoke(lease.LeaseID(lc.ID))
-	return &pb.LeaseRevokeResponse{Header: &pb.ResponseHeader{Revision: a.s.KV().Rev()}}, err
+	return &pb.LeaseRevokeResponse{Header: newHeader(a.s)}, err
 }
 
 func (a *applierV3backend) Alarm(ar *pb.AlarmRequest) (*pb.AlarmResponse, error) {
@@ -609,69 +608,125 @@ func (a *applierV3backend) AuthEnable() (*pb.AuthEnableResponse, error) {
 	if err != nil {
 		return nil, err
 	}
-	return &pb.AuthEnableResponse{}, nil
+	return &pb.AuthEnableResponse{Header: newHeader(a.s)}, nil
 }
 
 func (a *applierV3backend) AuthDisable() (*pb.AuthDisableResponse, error) {
 	a.s.AuthStore().AuthDisable()
-	return &pb.AuthDisableResponse{}, nil
+	return &pb.AuthDisableResponse{Header: newHeader(a.s)}, nil
 }
 
 func (a *applierV3backend) Authenticate(r *pb.InternalAuthenticateRequest) (*pb.AuthenticateResponse, error) {
-	ctx := context.WithValue(context.WithValue(context.TODO(), "index", a.s.consistIndex.ConsistentIndex()), "simpleToken", r.SimpleToken)
-	return a.s.AuthStore().Authenticate(ctx, r.Name, r.Password)
+	ctx := context.WithValue(context.WithValue(context.Background(), "index", a.s.consistIndex.ConsistentIndex()), "simpleToken", r.SimpleToken)
+	resp, err := a.s.AuthStore().Authenticate(ctx, r.Name, r.Password)
+	if resp != nil {
+		resp.Header = newHeader(a.s)
+	}
+	return resp, err
 }
 
 func (a *applierV3backend) UserAdd(r *pb.AuthUserAddRequest) (*pb.AuthUserAddResponse, error) {
-	return a.s.AuthStore().UserAdd(r)
+	resp, err := a.s.AuthStore().UserAdd(r)
+	if resp != nil {
+		resp.Header = newHeader(a.s)
+	}
+	return resp, err
 }
 
 func (a *applierV3backend) UserDelete(r *pb.AuthUserDeleteRequest) (*pb.AuthUserDeleteResponse, error) {
-	return a.s.AuthStore().UserDelete(r)
+	resp, err := a.s.AuthStore().UserDelete(r)
+	if resp != nil {
+		resp.Header = newHeader(a.s)
+	}
+	return resp, err
 }
 
 func (a *applierV3backend) UserChangePassword(r *pb.AuthUserChangePasswordRequest) (*pb.AuthUserChangePasswordResponse, error) {
-	return a.s.AuthStore().UserChangePassword(r)
+	resp, err := a.s.AuthStore().UserChangePassword(r)
+	if resp != nil {
+		resp.Header = newHeader(a.s)
+	}
+	return resp, err
 }
 
 func (a *applierV3backend) UserGrantRole(r *pb.AuthUserGrantRoleRequest) (*pb.AuthUserGrantRoleResponse, error) {
-	return a.s.AuthStore().UserGrantRole(r)
+	resp, err := a.s.AuthStore().UserGrantRole(r)
+	if resp != nil {
+		resp.Header = newHeader(a.s)
+	}
+	return resp, err
 }
 
 func (a *applierV3backend) UserGet(r *pb.AuthUserGetRequest) (*pb.AuthUserGetResponse, error) {
-	return a.s.AuthStore().UserGet(r)
+	resp, err := a.s.AuthStore().UserGet(r)
+	if resp != nil {
+		resp.Header = newHeader(a.s)
+	}
+	return resp, err
 }
 
 func (a *applierV3backend) UserRevokeRole(r *pb.AuthUserRevokeRoleRequest) (*pb.AuthUserRevokeRoleResponse, error) {
-	return a.s.AuthStore().UserRevokeRole(r)
+	resp, err := a.s.AuthStore().UserRevokeRole(r)
+	if resp != nil {
+		resp.Header = newHeader(a.s)
+	}
+	return resp, err
 }
 
 func (a *applierV3backend) RoleAdd(r *pb.AuthRoleAddRequest) (*pb.AuthRoleAddResponse, error) {
-	return a.s.AuthStore().RoleAdd(r)
+	resp, err := a.s.AuthStore().RoleAdd(r)
+	if resp != nil {
+		resp.Header = newHeader(a.s)
+	}
+	return resp, err
 }
 
 func (a *applierV3backend) RoleGrantPermission(r *pb.AuthRoleGrantPermissionRequest) (*pb.AuthRoleGrantPermissionResponse, error) {
-	return a.s.AuthStore().RoleGrantPermission(r)
+	resp, err := a.s.AuthStore().RoleGrantPermission(r)
+	if resp != nil {
+		resp.Header = newHeader(a.s)
+	}
+	return resp, err
 }
 
 func (a *applierV3backend) RoleGet(r *pb.AuthRoleGetRequest) (*pb.AuthRoleGetResponse, error) {
-	return a.s.AuthStore().RoleGet(r)
+	resp, err := a.s.AuthStore().RoleGet(r)
+	if resp != nil {
+		resp.Header = newHeader(a.s)
+	}
+	return resp, err
 }
 
 func (a *applierV3backend) RoleRevokePermission(r *pb.AuthRoleRevokePermissionRequest) (*pb.AuthRoleRevokePermissionResponse, error) {
-	return a.s.AuthStore().RoleRevokePermission(r)
+	resp, err := a.s.AuthStore().RoleRevokePermission(r)
+	if resp != nil {
+		resp.Header = newHeader(a.s)
+	}
+	return resp, err
 }
 
 func (a *applierV3backend) RoleDelete(r *pb.AuthRoleDeleteRequest) (*pb.AuthRoleDeleteResponse, error) {
-	return a.s.AuthStore().RoleDelete(r)
+	resp, err := a.s.AuthStore().RoleDelete(r)
+	if resp != nil {
+		resp.Header = newHeader(a.s)
+	}
+	return resp, err
 }
 
 func (a *applierV3backend) UserList(r *pb.AuthUserListRequest) (*pb.AuthUserListResponse, error) {
-	return a.s.AuthStore().UserList(r)
+	resp, err := a.s.AuthStore().UserList(r)
+	if resp != nil {
+		resp.Header = newHeader(a.s)
+	}
+	return resp, err
 }
 
 func (a *applierV3backend) RoleList(r *pb.AuthRoleListRequest) (*pb.AuthRoleListResponse, error) {
-	return a.s.AuthStore().RoleList(r)
+	resp, err := a.s.AuthStore().RoleList(r)
+	if resp != nil {
+		resp.Header = newHeader(a.s)
+	}
+	return resp, err
 }
 
 type quotaApplierV3 struct {
@@ -836,3 +891,12 @@ func pruneKVs(rr *mvcc.RangeResult, isPrunable func(*mvccpb.KeyValue) bool) {
 	}
 	rr.KVs = rr.KVs[:j]
 }
+
+func newHeader(s *EtcdServer) *pb.ResponseHeader {
+	return &pb.ResponseHeader{
+		ClusterId: uint64(s.Cluster().ID()),
+		MemberId:  uint64(s.ID()),
+		Revision:  s.KV().Rev(),
+		RaftTerm:  s.Term(),
+	}
+}

vendor/github.com/coreos/etcd/etcdserver/server.go

@@ -1253,9 +1253,14 @@ func (s *EtcdServer) apply(es []raftpb.Entry, confState *raftpb.ConfState) (appl
 		case raftpb.EntryNormal:
 			s.applyEntryNormal(&e)
 		case raftpb.EntryConfChange:
+			// set the consistent index of current executing entry
+			if e.Index > s.consistIndex.ConsistentIndex() {
+				s.consistIndex.setConsistentIndex(e.Index)
+			}
 			var cc raftpb.ConfChange
 			pbutil.MustUnmarshal(&cc, e.Data)
 			removedSelf, err := s.applyConfChange(cc, confState)
+			s.setAppliedIndex(e.Index)
 			shouldStop = shouldStop || removedSelf
 			s.w.Trigger(cc.ID, err)
 		default:

vendor/github.com/coreos/etcd/integration/bridge.go

@@ -31,8 +31,9 @@ type bridge struct {
 	l       net.Listener
 	conns   map[*bridgeConn]struct{}
 
-	stopc chan struct{}
-	wg    sync.WaitGroup
+	stopc  chan struct{}
+	pausec chan struct{}
+	wg     sync.WaitGroup
 
 	mu sync.Mutex
 }
@@ -43,8 +44,11 @@ func newBridge(addr string) (*bridge, error) {
 		inaddr:  addr + "0",
 		outaddr: addr,
 		conns:   make(map[*bridgeConn]struct{}),
-		stopc:   make(chan struct{}, 1),
+		stopc:   make(chan struct{}),
+		pausec:  make(chan struct{}),
 	}
+	close(b.pausec)
+
 	l, err := transport.NewUnixListener(b.inaddr)
 	if err != nil {
 		return nil, fmt.Errorf("listen failed on socket %s (%v)", addr, err)
@@ -59,10 +63,13 @@ func (b *bridge) URL() string { return "unix://" + b.inaddr }
 
 func (b *bridge) Close() {
 	b.l.Close()
+	b.mu.Lock()
 	select {
-	case b.stopc <- struct{}{}:
+	case <-b.stopc:
 	default:
+		close(b.stopc)
 	}
+	b.mu.Unlock()
 	b.wg.Wait()
 }
 
@@ -75,6 +82,22 @@ func (b *bridge) Reset() {
 	b.conns = make(map[*bridgeConn]struct{})
 }
 
+func (b *bridge) Pause() {
+	b.mu.Lock()
+	b.pausec = make(chan struct{})
+	b.mu.Unlock()
+}
+
+func (b *bridge) Unpause() {
+	b.mu.Lock()
+	select {
+	case <-b.pausec:
+	default:
+		close(b.pausec)
+	}
+	b.mu.Unlock()
+}
+
 func (b *bridge) serveListen() {
 	defer func() {
 		b.l.Close()
@@ -91,13 +114,23 @@ func (b *bridge) serveListen() {
 		if ierr != nil {
 			return
 		}
+		b.mu.Lock()
+		pausec := b.pausec
+		b.mu.Unlock()
+		select {
+		case <-b.stopc:
+			inc.Close()
+			return
+		case <-pausec:
+		}
+
 		outc, oerr := net.Dial("unix", b.outaddr)
 		if oerr != nil {
 			inc.Close()
 			return
 		}
 
-		bc := &bridgeConn{inc, outc}
+		bc := &bridgeConn{inc, outc, make(chan struct{})}
 		b.wg.Add(1)
 		b.mu.Lock()
 		b.conns[bc] = struct{}{}
@@ -108,6 +141,7 @@ func (b *bridge) serveListen() {
 
 func (b *bridge) serveConn(bc *bridgeConn) {
 	defer func() {
+		close(bc.donec)
 		bc.Close()
 		b.mu.Lock()
 		delete(b.conns, bc)
@@ -119,21 +153,29 @@ func (b *bridge) serveConn(bc *bridgeConn) {
 	wg.Add(2)
 	go func() {
 		io.Copy(bc.out, bc.in)
+		bc.close()
 		wg.Done()
 	}()
 	go func() {
 		io.Copy(bc.in, bc.out)
+		bc.close()
 		wg.Done()
 	}()
 	wg.Wait()
 }
 
 type bridgeConn struct {
-	in  net.Conn
-	out net.Conn
+	in    net.Conn
+	out   net.Conn
+	donec chan struct{}
 }
 
 func (bc *bridgeConn) Close() {
+	bc.close()
+	<-bc.donec
+}
+
+func (bc *bridgeConn) close() {
 	bc.in.Close()
 	bc.out.Close()
 }

vendor/github.com/coreos/etcd/integration/cluster.go

@@ -532,7 +532,9 @@ func (m *member) electionTimeout() time.Duration {
 	return time.Duration(m.s.Cfg.ElectionTicks) * time.Millisecond
 }
 
-func (m *member) DropConnections() { m.grpcBridge.Reset() }
+func (m *member) DropConnections()    { m.grpcBridge.Reset() }
+func (m *member) PauseConnections()   { m.grpcBridge.Pause() }
+func (m *member) UnpauseConnections() { m.grpcBridge.Unpause() }
 
 // NewClientV3 creates a new grpc client connection to the member
 func NewClientV3(m *member) (*clientv3.Client, error) {

vendor/github.com/coreos/etcd/pkg/transport/listener.go

@@ -28,7 +28,6 @@ import (
 	"net"
 	"os"
 	"path/filepath"
-	"strings"
 	"time"
 
 	"github.com/coreos/etcd/pkg/fileutil"
@@ -120,10 +119,11 @@ func SelfCert(dirpath string, hosts []string) (info TLSInfo, err error) {
 	}
 
 	for _, host := range hosts {
-		if ip := net.ParseIP(host); ip != nil {
+		h, _, _ := net.SplitHostPort(host)
+		if ip := net.ParseIP(h); ip != nil {
 			tmpl.IPAddresses = append(tmpl.IPAddresses, ip)
 		} else {
-			tmpl.DNSNames = append(tmpl.DNSNames, strings.Split(host, ":")[0])
+			tmpl.DNSNames = append(tmpl.DNSNames, h)
 		}
 	}
 

vendor/github.com/coreos/etcd/rafthttp/http.go

@@ -183,7 +183,8 @@ func (h *snapshotHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	}
 
 	dec := &messageDecoder{r: r.Body}
-	m, err := dec.decode()
+	// let snapshots be very large since they can exceed 512MB for large installations
+	m, err := dec.decodeLimit(uint64(1 << 63))
 	if err != nil {
 		msg := fmt.Sprintf("failed to decode raft message (%v)", err)
 		plog.Errorf(msg)

vendor/github.com/coreos/etcd/rafthttp/msg_codec.go

@@ -48,12 +48,16 @@ var (
 )
 
 func (dec *messageDecoder) decode() (raftpb.Message, error) {
+	return dec.decodeLimit(readBytesLimit)
+}
+
+func (dec *messageDecoder) decodeLimit(numBytes uint64) (raftpb.Message, error) {
 	var m raftpb.Message
 	var l uint64
 	if err := binary.Read(dec.r, binary.BigEndian, &l); err != nil {
 		return m, err
 	}
-	if l > readBytesLimit {
+	if l > numBytes {
 		return m, ErrExceedSizeLimit
 	}
 	buf := make([]byte, int(l))

vendor/github.com/coreos/etcd/version/version.go

@@ -26,7 +26,7 @@ import (
 var (
 	// MinClusterVersion is the min cluster version this etcd binary is compatible with.
 	MinClusterVersion = "3.0.0"
-	Version           = "3.1.5"
+	Version           = "3.1.10"
 	APIVersion        = "unknown"
 
 	// Git SHA Value will be set during build

vendor/github.com/coreos/go-oidc/http/http.go

@@ -91,7 +91,12 @@ func expires(date, expires string) (time.Duration, bool, error) {
 		return 0, false, nil
 	}
 
-	te, err := time.Parse(time.RFC1123, expires)
+	var te time.Time
+	var err error
+	if expires == "0" {
+		return 0, false, nil
+	}
+	te, err = time.Parse(time.RFC1123, expires)
 	if err != nil {
 		return 0, false, err
 	}

vendor/github.com/evanphx/json-patch/.travis.yml

@@ -1,13 +1,15 @@
 language: go
 
 go:
-  - 1.4
-  - 1.3
+  - 1.8
+  - 1.7
 
 install:
   - if ! go get code.google.com/p/go.tools/cmd/cover; then go get golang.org/x/tools/cmd/cover; fi
+  - go get github.com/jessevdk/go-flags
 
 script:
+  - go get
   - go test -cover ./...
 
 notifications:

vendor/github.com/evanphx/json-patch/merge.go

@@ -4,7 +4,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"reflect"
-	"strings"
 )
 
 func merge(cur, patch *lazyNode, mergeMerge bool) *lazyNode {
@@ -28,7 +27,6 @@ func merge(cur, patch *lazyNode, mergeMerge bool) *lazyNode {
 
 func mergeDocs(doc, patch *partialDoc, mergeMerge bool) {
 	for k, v := range *patch {
-		k := decodePatchKey(k)
 		if v == nil {
 			if mergeMerge {
 				(*doc)[k] = nil
@@ -226,6 +224,9 @@ func matchesValue(av, bv interface{}) bool {
 		if bt == at {
 			return true
 		}
+	case nil:
+		// Both nil, fine.
+		return true
 	case map[string]interface{}:
 		bt := bv.(map[string]interface{})
 		for key := range at {
@@ -250,16 +251,15 @@ func matchesValue(av, bv interface{}) bool {
 func getDiff(a, b map[string]interface{}) (map[string]interface{}, error) {
 	into := map[string]interface{}{}
 	for key, bv := range b {
-		escapedKey := encodePatchKey(key)
 		av, ok := a[key]
 		// value was added
 		if !ok {
-			into[escapedKey] = bv
+			into[key] = bv
 			continue
 		}
 		// If types have changed, replace completely
 		if reflect.TypeOf(av) != reflect.TypeOf(bv) {
-			into[escapedKey] = bv
+			into[key] = bv
 			continue
 		}
 		// Types are the same, compare values
@@ -272,23 +272,23 @@ func getDiff(a, b map[string]interface{}) (map[string]interface{}, error) {
 				return nil, err
 			}
 			if len(dst) > 0 {
-				into[escapedKey] = dst
+				into[key] = dst
 			}
 		case string, float64, bool:
 			if !matchesValue(av, bv) {
-				into[escapedKey] = bv
+				into[key] = bv
 			}
 		case []interface{}:
 			bt := bv.([]interface{})
 			if !matchesArray(at, bt) {
-				into[escapedKey] = bv
+				into[key] = bv
 			}
 		case nil:
 			switch bv.(type) {
 			case nil:
 				// Both nil, fine.
 			default:
-				into[escapedKey] = bv
+				into[key] = bv
 			}
 		default:
 			panic(fmt.Sprintf("Unknown type:%T in key %s", av, key))
@@ -303,23 +303,3 @@ func getDiff(a, b map[string]interface{}) (map[string]interface{}, error) {
 	}
 	return into, nil
 }
-
-// From http://tools.ietf.org/html/rfc6901#section-4 :
-//
-// Evaluation of each reference token begins by decoding any escaped
-// character sequence.  This is performed by first transforming any
-// occurrence of the sequence '~1' to '/', and then transforming any
-// occurrence of the sequence '~0' to '~'.
-
-var (
-	rfc6901Encoder = strings.NewReplacer("~", "~0", "/", "~1")
-	rfc6901Decoder = strings.NewReplacer("~1", "/", "~0", "~")
-)
-
-func decodePatchKey(k string) string {
-	return rfc6901Decoder.Replace(k)
-}
-
-func encodePatchKey(k string) string {
-	return rfc6901Encoder.Replace(k)
-}

vendor/github.com/evanphx/json-patch/patch.go

@@ -369,6 +369,15 @@ func (d *partialArray) add(key string, val *lazyNode) error {
 
 	cur := *d
 
+	if idx < 0 {
+		idx *= -1
+
+		if idx > len(ary) {
+			return fmt.Errorf("Unable to access invalid index: %d", idx)
+		}
+		idx = len(ary) - idx
+	}
+
 	copy(ary[0:idx], cur[0:idx])
 	ary[idx] = val
 	copy(ary[idx+1:], cur[idx:])
@@ -446,6 +455,11 @@ func (p Patch) replace(doc *container, op operation) error {
 		return fmt.Errorf("jsonpatch replace operation does not apply: doc is missing path: %s", path)
 	}
 
+	val, ok := con.get(key)
+	if val == nil || ok != nil {
+		return fmt.Errorf("jsonpatch replace operation does not apply: doc is missing key: %s", path)
+	}
+
 	return con.set(key, op.value())
 }
 
@@ -508,6 +522,31 @@ func (p Patch) test(doc *container, op operation) error {
 	return fmt.Errorf("Testing value %s failed", path)
 }
 
+func (p Patch) copy(doc *container, op operation) error {
+	from := op.from()
+
+	con, key := findObject(doc, from)
+
+	if con == nil {
+		return fmt.Errorf("jsonpatch copy operation does not apply: doc is missing from path: %s", from)
+	}
+
+	val, err := con.get(key)
+	if err != nil {
+		return err
+	}
+
+	path := op.path()
+
+	con, key = findObject(doc, path)
+
+	if con == nil {
+		return fmt.Errorf("jsonpatch copy operation does not apply: doc is missing destination path: %s", path)
+	}
+
+	return con.set(key, val)
+}
+
 // Equal indicates if 2 JSON documents have the same structural equality.
 func Equal(a, b []byte) bool {
 	ra := make(json.RawMessage, len(a))
@@ -570,6 +609,8 @@ func (p Patch) ApplyIndent(doc []byte, indent string) ([]byte, error) {
 			err = p.move(&pd, op)
 		case "test":
 			err = p.test(&pd, op)
+		case "copy":
+			err = p.copy(&pd, op)
 		default:
 			err = fmt.Errorf("Unexpected kind: %s", op.kind())
 		}
@@ -585,3 +626,18 @@ func (p Patch) ApplyIndent(doc []byte, indent string) ([]byte, error) {
 
 	return json.Marshal(pd)
 }
+
+// From http://tools.ietf.org/html/rfc6901#section-4 :
+//
+// Evaluation of each reference token begins by decoding any escaped
+// character sequence.  This is performed by first transforming any
+// occurrence of the sequence '~1' to '/', and then transforming any
+// occurrence of the sequence '~0' to '~'.
+
+var (
+	rfc6901Decoder = strings.NewReplacer("~1", "/", "~0", "~")
+)
+
+func decodePatchKey(k string) string {
+	return rfc6901Decoder.Replace(k)
+}

vendor/github.com/googleapis/gnostic/OpenAPIv2/OpenAPIv2.pb.go

@@ -1376,7 +1376,7 @@ func (m *ItemsItem) GetSchema() []*Schema {
 }
 
 type JsonReference struct {
-	XRef        string `protobuf:"bytes,1,opt,name=_ref,json=ref" json:"_ref,omitempty"`
+	XRef        string `protobuf:"bytes,1,opt,name=_ref,json=Ref" json:"_ref,omitempty"`
 	Description string `protobuf:"bytes,2,opt,name=description" json:"description,omitempty"`
 }
 
@@ -2513,7 +2513,7 @@ func _ParametersItem_OneofSizer(msg proto.Message) (n int) {
 }
 
 type PathItem struct {
-	XRef    string     `protobuf:"bytes,1,opt,name=_ref,json=ref" json:"_ref,omitempty"`
+	XRef    string     `protobuf:"bytes,1,opt,name=_ref,json=Ref" json:"_ref,omitempty"`
 	Get     *Operation `protobuf:"bytes,2,opt,name=get" json:"get,omitempty"`
 	Put     *Operation `protobuf:"bytes,3,opt,name=put" json:"put,omitempty"`
 	Post    *Operation `protobuf:"bytes,4,opt,name=post" json:"post,omitempty"`
@@ -3392,7 +3392,7 @@ func (m *Responses) GetVendorExtension() []*NamedAny {
 
 // A deterministic version of a JSON Schema object.
 type Schema struct {
-	XRef                 string                    `protobuf:"bytes,1,opt,name=_ref,json=ref" json:"_ref,omitempty"`
+	XRef                 string                    `protobuf:"bytes,1,opt,name=_ref,json=Ref" json:"_ref,omitempty"`
 	Format               string                    `protobuf:"bytes,2,opt,name=format" json:"format,omitempty"`
 	Title                string                    `protobuf:"bytes,3,opt,name=title" json:"title,omitempty"`
 	Description          string                    `protobuf:"bytes,4,opt,name=description" json:"description,omitempty"`
@@ -4351,7 +4351,7 @@ var fileDescriptor0 = []byte{
 	0xfe, 0x90, 0x83, 0x0c, 0x89, 0xa3, 0x14, 0x7e, 0x7d, 0x1e, 0xe1, 0xbf, 0x05, 0x4d, 0xa6, 0x0c,
 	0xac, 0x56, 0x77, 0x23, 0x51, 0xab, 0x2b, 0x4f, 0x2e, 0xac, 0x6c, 0xdd, 0x85, 0xd6, 0x37, 0x02,
 	0xe2, 0x1a, 0x78, 0x80, 0x7d, 0xec, 0xf6, 0xb0, 0xb6, 0x0c, 0x15, 0xd3, 0xc7, 0x03, 0x21, 0xe3,
-	0xb2, 0x8f, 0x07, 0xd3, 0xeb, 0x4f, 0x5b, 0x1e, 0xd4, 0xc5, 0x33, 0xcd, 0x58, 0x5c, 0x39, 0xf3,
+	0xb2, 0x81, 0x07, 0xd3, 0xeb, 0x4f, 0x5b, 0x1e, 0xd4, 0xc5, 0x33, 0xcd, 0x58, 0x5c, 0x39, 0xf3,
 	0x59, 0xe6, 0x1e, 0x34, 0x24, 0x50, 0xb9, 0xe5, 0x2b, 0xb2, 0xaa, 0x58, 0x52, 0x3b, 0x20, 0x0e,
 	0xdd, 0x7a, 0x17, 0x16, 0x12, 0x0a, 0xa8, 0xa4, 0x74, 0x2d, 0x4d, 0x29, 0x25, 0x4c, 0xa1, 0xb7,
 	0x82, 0xd8, 0xfb, 0xd0, 0x66, 0xc4, 0xe2, 0x22, 0x9a, 0x8a, 0xde, 0xeb, 0x69, 0x7a, 0x17, 0x94,
@@ -4452,5 +4452,5 @@ var fileDescriptor0 = []byte{
 	0xf3, 0x70, 0x5f, 0x1c, 0xc1, 0xe5, 0xf0, 0xcc, 0x7d, 0xcc, 0xdb, 0xaf, 0x42, 0x9b, 0xf8, 0x47,
 	0x12, 0xd7, 0x3c, 0xd9, 0xb9, 0xbd, 0x28, 0xbe, 0x5d, 0xdd, 0xf7, 0x49, 0x48, 0xf6, 0x8b, 0xbf,
 	0x28, 0x95, 0xf7, 0x76, 0x0f, 0x0e, 0x6b, 0xec, 0x63, 0xd0, 0x37, 0xff, 0x19, 0x00, 0x00, 0xff,
-	0xff, 0x3c, 0x01, 0x3f, 0x38, 0xe4, 0x3a, 0x00, 0x00,
+	0xff, 0xd4, 0x0a, 0xef, 0xca, 0xe4, 0x3a, 0x00, 0x00,
 }

vendor/github.com/googleapis/gnostic/compiler/context.go

@@ -14,28 +14,30 @@
 
 package compiler
 
+// Context contains state of the compiler as it traverses a document.
 type Context struct {
 	Parent            *Context
 	Name              string
 	ExtensionHandlers *[]ExtensionHandler
 }
 
+// NewContextWithExtensions returns a new object representing the compiler state
 func NewContextWithExtensions(name string, parent *Context, extensionHandlers *[]ExtensionHandler) *Context {
 	return &Context{Name: name, Parent: parent, ExtensionHandlers: extensionHandlers}
 }
 
+// NewContext returns a new object representing the compiler state
 func NewContext(name string, parent *Context) *Context {
 	if parent != nil {
 		return &Context{Name: name, Parent: parent, ExtensionHandlers: parent.ExtensionHandlers}
-	} else {
-		return &Context{Name: name, Parent: parent, ExtensionHandlers: nil}
 	}
+	return &Context{Name: name, Parent: parent, ExtensionHandlers: nil}
 }
 
+// Description returns a text description of the compiler state
 func (context *Context) Description() string {
 	if context.Parent != nil {
 		return context.Parent.Description() + "." + context.Name
-	} else {
-		return context.Name
 	}
+	return context.Name
 }

vendor/github.com/googleapis/gnostic/compiler/error.go

@@ -14,29 +14,31 @@
 
 package compiler
 
-// basic error type
+// Error represents compiler errors and their location in the document.
 type Error struct {
 	Context *Context
 	Message string
 }
 
+// NewError creates an Error.
 func NewError(context *Context, message string) *Error {
 	return &Error{Context: context, Message: message}
 }
 
+// Error returns the string value of an Error.
 func (err *Error) Error() string {
-	if err.Context != nil {
-		return "ERROR " + err.Context.Description() + " " + err.Message
-	} else {
+	if err.Context == nil {
 		return "ERROR " + err.Message
 	}
+	return "ERROR " + err.Context.Description() + " " + err.Message
 }
 
-// container for groups of errors
+// ErrorGroup is a container for groups of Error values.
 type ErrorGroup struct {
 	Errors []error
 }
 
+// NewErrorGroupOrNil returns a new ErrorGroup for a slice of errors or nil if the slice is empty.
 func NewErrorGroupOrNil(errors []error) error {
 	if len(errors) == 0 {
 		return nil

vendor/github.com/googleapis/gnostic/compiler/extension-handler.go

@@ -29,16 +29,18 @@ import (
 	yaml "gopkg.in/yaml.v2"
 )
 
+// ExtensionHandler describes a binary that is called by the compiler to handle specification extensions.
 type ExtensionHandler struct {
 	Name string
 }
 
+// HandleExtension calls a binary extension handler.
 func HandleExtension(context *Context, in interface{}, extensionName string) (bool, *any.Any, error) {
 	handled := false
 	var errFromPlugin error
 	var outFromPlugin *any.Any
 
-	if context.ExtensionHandlers != nil && len(*(context.ExtensionHandlers)) != 0 {
+	if context != nil && context.ExtensionHandlers != nil && len(*(context.ExtensionHandlers)) != 0 {
 		for _, customAnyProtoGenerator := range *(context.ExtensionHandlers) {
 			outFromPlugin, errFromPlugin = customAnyProtoGenerator.handle(in, extensionName)
 			if outFromPlugin == nil {

vendor/github.com/googleapis/gnostic/compiler/helpers.go

@@ -19,27 +19,27 @@ import (
 	"gopkg.in/yaml.v2"
 	"regexp"
 	"sort"
-	"strings"
+	"strconv"
 )
 
 // compiler helper functions, usually called from generated code
 
+// UnpackMap gets a yaml.MapSlice if possible.
 func UnpackMap(in interface{}) (yaml.MapSlice, bool) {
 	m, ok := in.(yaml.MapSlice)
 	if ok {
-		return m, ok
-	} else {
-		// do we have an empty array?
-		a, ok := in.([]interface{})
-		if ok && len(a) == 0 {
-			// if so, return an empty map
-			return yaml.MapSlice{}, ok
-		} else {
-			return nil, ok
-		}
+		return m, true
 	}
+	// do we have an empty array?
+	a, ok := in.([]interface{})
+	if ok && len(a) == 0 {
+		// if so, return an empty map
+		return yaml.MapSlice{}, true
+	}
+	return nil, false
 }
 
+// SortedKeysForMap returns the sorted keys of a yaml.MapSlice.
 func SortedKeysForMap(m yaml.MapSlice) []string {
 	keys := make([]string, 0)
 	for _, item := range m {
@@ -49,6 +49,7 @@ func SortedKeysForMap(m yaml.MapSlice) []string {
 	return keys
 }
 
+// MapHasKey returns true if a yaml.MapSlice contains a specified key.
 func MapHasKey(m yaml.MapSlice, key string) bool {
 	for _, item := range m {
 		itemKey, ok := item.Key.(string)
@@ -59,6 +60,7 @@ func MapHasKey(m yaml.MapSlice, key string) bool {
 	return false
 }
 
+// MapValueForKey gets the value of a map value for a specified key.
 func MapValueForKey(m yaml.MapSlice, key string) interface{} {
 	for _, item := range m {
 		itemKey, ok := item.Key.(string)
@@ -69,6 +71,7 @@ func MapValueForKey(m yaml.MapSlice, key string) interface{} {
 	return nil
 }
 
+// ConvertInterfaceArrayToStringArray converts an array of interfaces to an array of strings, if possible.
 func ConvertInterfaceArrayToStringArray(interfaceArray []interface{}) []string {
 	stringArray := make([]string, 0)
 	for _, item := range interfaceArray {
@@ -80,22 +83,7 @@ func ConvertInterfaceArrayToStringArray(interfaceArray []interface{}) []string {
 	return stringArray
 }
 
-func PatternMatches(pattern string, value string) bool {
-	// if pattern contains a subpattern like "{path}", replace it with ".*"
-	if pattern[0] != '^' {
-		subpatternPattern := regexp.MustCompile("^.*(\\{.*\\}).*$")
-		if matches := subpatternPattern.FindSubmatch([]byte(pattern)); matches != nil {
-			match := string(matches[1])
-			pattern = strings.Replace(pattern, match, ".*", -1)
-		}
-	}
-	matched, err := regexp.Match(pattern, []byte(value))
-	if err != nil {
-		panic(err)
-	}
-	return matched
-}
-
+// MissingKeysInMap identifies which keys from a list of required keys are not in a map.
 func MissingKeysInMap(m yaml.MapSlice, requiredKeys []string) []string {
 	missingKeys := make([]string, 0)
 	for _, k := range requiredKeys {
@@ -106,7 +94,8 @@ func MissingKeysInMap(m yaml.MapSlice, requiredKeys []string) []string {
 	return missingKeys
 }
 
-func InvalidKeysInMap(m yaml.MapSlice, allowedKeys []string, allowedPatterns []string) []string {
+// InvalidKeysInMap returns keys in a map that don't match a list of allowed keys and patterns.
+func InvalidKeysInMap(m yaml.MapSlice, allowedKeys []string, allowedPatterns []*regexp.Regexp) []string {
 	invalidKeys := make([]string, 0)
 	for _, item := range m {
 		itemKey, ok := item.Key.(string)
@@ -123,7 +112,7 @@ func InvalidKeysInMap(m yaml.MapSlice, allowedKeys []string, allowedPatterns []s
 			if !found {
 				// does the key match an allowed pattern?
 				for _, allowedPattern := range allowedPatterns {
-					if PatternMatches(allowedPattern, key) {
+					if allowedPattern.MatchString(key) {
 						found = true
 						break
 					}
@@ -137,13 +126,13 @@ func InvalidKeysInMap(m yaml.MapSlice, allowedKeys []string, allowedPatterns []s
 	return invalidKeys
 }
 
-// describe a map (for debugging purposes)
+// DescribeMap describes a map (for debugging purposes).
 func DescribeMap(in interface{}, indent string) string {
 	description := ""
 	m, ok := in.(map[string]interface{})
 	if ok {
 		keys := make([]string, 0)
-		for k, _ := range m {
+		for k := range m {
 			keys = append(keys, k)
 		}
 		sort.Strings(keys)
@@ -166,14 +155,15 @@ func DescribeMap(in interface{}, indent string) string {
 	return description
 }
 
+// PluralProperties returns the string "properties" pluralized.
 func PluralProperties(count int) string {
 	if count == 1 {
 		return "property"
-	} else {
-		return "properties"
 	}
+	return "properties"
 }
 
+// StringArrayContainsValue returns true if a string array contains a specified value.
 func StringArrayContainsValue(array []string, value string) bool {
 	for _, item := range array {
 		if item == value {
@@ -183,6 +173,7 @@ func StringArrayContainsValue(array []string, value string) bool {
 	return false
 }
 
+// StringArrayContainsValues returns true if a string array contains all of a list of specified values.
 func StringArrayContainsValues(array []string, values []string) bool {
 	for _, value := range values {
 		if !StringArrayContainsValue(array, value) {
@@ -191,3 +182,16 @@ func StringArrayContainsValues(array []string, values []string) bool {
 	}
 	return true
 }
+
+// StringValue returns the string value of an item.
+func StringValue(item interface{}) (value string, ok bool) {
+	value, ok = item.(string)
+	if ok {
+		return value, ok
+	}
+	intValue, ok := item.(int)
+	if ok {
+		return strconv.Itoa(intValue), true
+	}
+	return "", false
+}

vendor/github.com/googleapis/gnostic/compiler/reader.go

@@ -25,29 +25,30 @@ import (
 	"strings"
 )
 
-var file_cache map[string][]byte
-var info_cache map[string]interface{}
+var fileCache map[string][]byte
+var infoCache map[string]interface{}
 var count int64
 
-var VERBOSE_READER = false
+var verboseReader = false
 
 func initializeFileCache() {
-	if file_cache == nil {
-		file_cache = make(map[string][]byte, 0)
+	if fileCache == nil {
+		fileCache = make(map[string][]byte, 0)
 	}
 }
 
 func initializeInfoCache() {
-	if info_cache == nil {
-		info_cache = make(map[string]interface{}, 0)
+	if infoCache == nil {
+		infoCache = make(map[string]interface{}, 0)
 	}
 }
 
+// FetchFile gets a specified file from the local filesystem or a remote location.
 func FetchFile(fileurl string) ([]byte, error) {
 	initializeFileCache()
-	bytes, ok := file_cache[fileurl]
+	bytes, ok := fileCache[fileurl]
 	if ok {
-		if VERBOSE_READER {
+		if verboseReader {
 			log.Printf("Cache hit %s", fileurl)
 		}
 		return bytes, nil
@@ -56,30 +57,17 @@ func FetchFile(fileurl string) ([]byte, error) {
 	response, err := http.Get(fileurl)
 	if err != nil {
 		return nil, err
-	} else {
-		defer response.Body.Close()
-		bytes, err := ioutil.ReadAll(response.Body)
-		if err == nil {
-			file_cache[fileurl] = bytes
-		}
-		return bytes, err
 	}
+	defer response.Body.Close()
+	bytes, err = ioutil.ReadAll(response.Body)
+	if err == nil {
+		fileCache[fileurl] = bytes
+	}
+	return bytes, err
 }
 
-// read a file and unmarshal it as a yaml.MapSlice
-func ReadInfoForFile(filename string) (interface{}, error) {
-	initializeInfoCache()
-	info, ok := info_cache[filename]
-	if ok {
-		if VERBOSE_READER {
-			log.Printf("Cache hit info for file %s", filename)
-		}
-		return info, nil
-	}
-	if VERBOSE_READER {
-		log.Printf("Reading info for file %s", filename)
-	}
-
+// ReadBytesForFile reads the bytes of a file.
+func ReadBytesForFile(filename string) ([]byte, error) {
 	// is the filename a url?
 	fileurl, _ := url.Parse(filename)
 	if fileurl.Scheme != "" {
@@ -88,43 +76,51 @@ func ReadInfoForFile(filename string) (interface{}, error) {
 		if err != nil {
 			return nil, err
 		}
-		var info yaml.MapSlice
-		err = yaml.Unmarshal(bytes, &info)
-		if err != nil {
-			return nil, err
-		}
-		info_cache[filename] = info
-		return info, nil
-	} else {
-		// no, it's a local filename
-		bytes, err := ioutil.ReadFile(filename)
-		if err != nil {
-			log.Printf("File error: %v\n", err)
-			return nil, err
-		}
-		var info yaml.MapSlice
-		err = yaml.Unmarshal(bytes, &info)
-		if err != nil {
-			return nil, err
-		}
-		info_cache[filename] = info
-		return info, nil
+		return bytes, nil
 	}
+	// no, it's a local filename
+	bytes, err := ioutil.ReadFile(filename)
+	if err != nil {
+		return nil, err
+	}
+	return bytes, nil
 }
 
-// read a file and return the fragment needed to resolve a $ref
+// ReadInfoFromBytes unmarshals a file as a yaml.MapSlice.
+func ReadInfoFromBytes(filename string, bytes []byte) (interface{}, error) {
+	initializeInfoCache()
+	cachedInfo, ok := infoCache[filename]
+	if ok {
+		if verboseReader {
+			log.Printf("Cache hit info for file %s", filename)
+		}
+		return cachedInfo, nil
+	}
+	if verboseReader {
+		log.Printf("Reading info for file %s", filename)
+	}
+	var info yaml.MapSlice
+	err := yaml.Unmarshal(bytes, &info)
+	if err != nil {
+		return nil, err
+	}
+	infoCache[filename] = info
+	return info, nil
+}
+
+// ReadInfoForRef reads a file and return the fragment needed to resolve a $ref.
 func ReadInfoForRef(basefile string, ref string) (interface{}, error) {
 	initializeInfoCache()
 	{
-		info, ok := info_cache[ref]
+		info, ok := infoCache[ref]
 		if ok {
-			if VERBOSE_READER {
+			if verboseReader {
 				log.Printf("Cache hit for ref %s#%s", basefile, ref)
 			}
 			return info, nil
 		}
 	}
-	if VERBOSE_READER {
+	if verboseReader {
 		log.Printf("Reading info for ref %s#%s", basefile, ref)
 	}
 	count = count + 1
@@ -136,7 +132,11 @@ func ReadInfoForRef(basefile string, ref string) (interface{}, error) {
 	} else {
 		filename = basefile
 	}
-	info, err := ReadInfoForFile(filename)
+	bytes, err := ReadBytesForFile(filename)
+	if err != nil {
+		return nil, err
+	}
+	info, err := ReadInfoFromBytes(filename, bytes)
 	if err != nil {
 		log.Printf("File error: %v\n", err)
 	} else {
@@ -154,7 +154,7 @@ func ReadInfoForRef(basefile string, ref string) (interface{}, error) {
 							}
 						}
 						if !found {
-							info_cache[ref] = nil
+							infoCache[ref] = nil
 							return nil, NewError(nil, fmt.Sprintf("could not resolve %s", ref))
 						}
 					}
@@ -162,6 +162,6 @@ func ReadInfoForRef(basefile string, ref string) (interface{}, error) {
 			}
 		}
 	}
-	info_cache[ref] = info
+	infoCache[ref] = info
 	return info, nil
 }

vendor/github.com/googleapis/gnostic/extensions/COMPILE-EXTENSION.sh

@@ -3,5 +3,3 @@ go get github.com/golang/protobuf/protoc-gen-go
 protoc \
 --go_out=Mgoogle/protobuf/any.proto=github.com/golang/protobuf/ptypes/any:. *.proto 
 
-go build
-go install

vendor/github.com/googleapis/gnostic/extensions/extensions.go

@@ -21,40 +21,39 @@ import (
 
 	"github.com/golang/protobuf/proto"
 	"github.com/golang/protobuf/ptypes"
-	"gopkg.in/yaml.v2"
 )
 
 type documentHandler func(version string, extensionName string, document string)
-type extensionHandler func(name string, info yaml.MapSlice) (bool, proto.Message, error)
+type extensionHandler func(name string, yamlInput string) (bool, proto.Message, error)
 
 func forInputYamlFromOpenapic(handler documentHandler) {
 	data, err := ioutil.ReadAll(os.Stdin)
-
 	if err != nil {
 		fmt.Println("File error:", err.Error())
 		os.Exit(1)
 	}
+	if len(data) == 0 {
+		fmt.Println("No input data.")
+		os.Exit(1)
+	}
 	request := &ExtensionHandlerRequest{}
 	err = proto.Unmarshal(data, request)
+	if err != nil {
+		fmt.Println("Input error:", err.Error())
+		os.Exit(1)
+	}
 	handler(request.Wrapper.Version, request.Wrapper.ExtensionName, request.Wrapper.Yaml)
 }
 
+// ProcessExtension calles the handler for a specified extension.
 func ProcessExtension(handleExtension extensionHandler) {
 	response := &ExtensionHandlerResponse{}
 	forInputYamlFromOpenapic(
 		func(version string, extensionName string, yamlInput string) {
-			var info yaml.MapSlice
 			var newObject proto.Message
 			var err error
-			err = yaml.Unmarshal([]byte(yamlInput), &info)
-			if err != nil {
-				response.Error = append(response.Error, err.Error())
-				responseBytes, _ := proto.Marshal(response)
-				os.Stdout.Write(responseBytes)
-				os.Exit(0)
-			}
 
-			handled, newObject, err := handleExtension(extensionName, info)
+			handled, newObject, err := handleExtension(extensionName, yamlInput)
 			if !handled {
 				responseBytes, _ := proto.Marshal(response)
 				os.Stdout.Write(responseBytes)

vendor/github.com/gregjones/httpcache/.travis.yml

@@ -0,0 +1,18 @@
+sudo: false
+language: go
+go:
+  - 1.6.x
+  - 1.7.x
+  - 1.8.x
+  - master
+matrix:
+  allow_failures:
+    - go: master
+  fast_finish: true
+install:
+  - # Do nothing. This is needed to prevent default install action "go get -t -v ./..." from happening here (we want it to happen inside script step).
+script:
+  - go get -t -v ./...
+  - diff -u <(echo -n) <(gofmt -d .)
+  - go tool vet .
+  - go test -v -race ./...

vendor/github.com/gregjones/httpcache/LICENSE.txt

@@ -0,0 +1,7 @@
+Copyright © 2012 Greg Jones (greg.jones@gmail.com)
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

vendor/github.com/gregjones/httpcache/README.md

@@ -0,0 +1,24 @@
+httpcache
+=========
+
+[![Build Status](https://travis-ci.org/gregjones/httpcache.svg?branch=master)](https://travis-ci.org/gregjones/httpcache) [![GoDoc](https://godoc.org/github.com/gregjones/httpcache?status.svg)](https://godoc.org/github.com/gregjones/httpcache)
+
+Package httpcache provides a http.RoundTripper implementation that works as a mostly RFC-compliant cache for http responses.
+
+It is only suitable for use as a 'private' cache (i.e. for a web-browser or an API-client and not for a shared proxy).
+
+Cache Backends
+--------------
+
+- The built-in 'memory' cache stores responses in an in-memory map.
+- [`github.com/gregjones/httpcache/diskcache`](https://github.com/gregjones/httpcache/tree/master/diskcache) provides a filesystem-backed cache using the [diskv](https://github.com/peterbourgon/diskv) library.
+- [`github.com/gregjones/httpcache/memcache`](https://github.com/gregjones/httpcache/tree/master/memcache) provides memcache implementations, for both App Engine and 'normal' memcache servers.
+- [`sourcegraph.com/sourcegraph/s3cache`](https://sourcegraph.com/github.com/sourcegraph/s3cache) uses Amazon S3 for storage.
+- [`github.com/gregjones/httpcache/leveldbcache`](https://github.com/gregjones/httpcache/tree/master/leveldbcache) provides a filesystem-backed cache using [leveldb](https://github.com/syndtr/goleveldb/leveldb).
+- [`github.com/die-net/lrucache`](https://github.com/die-net/lrucache) provides an in-memory cache that will evict least-recently used entries.
+- [`github.com/die-net/lrucache/twotier`](https://github.com/die-net/lrucache/tree/master/twotier) allows caches to be combined, for example to use lrucache above with a persistent disk-cache.
+
+License
+-------
+
+-	[MIT License](LICENSE.txt)

vendor/github.com/gregjones/httpcache/diskcache/diskcache.go

@@ -0,0 +1,61 @@
+// Package diskcache provides an implementation of httpcache.Cache that uses the diskv package
+// to supplement an in-memory map with persistent storage
+//
+package diskcache
+
+import (
+	"bytes"
+	"crypto/md5"
+	"encoding/hex"
+	"github.com/peterbourgon/diskv"
+	"io"
+)
+
+// Cache is an implementation of httpcache.Cache that supplements the in-memory map with persistent storage
+type Cache struct {
+	d *diskv.Diskv
+}
+
+// Get returns the response corresponding to key if present
+func (c *Cache) Get(key string) (resp []byte, ok bool) {
+	key = keyToFilename(key)
+	resp, err := c.d.Read(key)
+	if err != nil {
+		return []byte{}, false
+	}
+	return resp, true
+}
+
+// Set saves a response to the cache as key
+func (c *Cache) Set(key string, resp []byte) {
+	key = keyToFilename(key)
+	c.d.WriteStream(key, bytes.NewReader(resp), true)
+}
+
+// Delete removes the response with key from the cache
+func (c *Cache) Delete(key string) {
+	key = keyToFilename(key)
+	c.d.Erase(key)
+}
+
+func keyToFilename(key string) string {
+	h := md5.New()
+	io.WriteString(h, key)
+	return hex.EncodeToString(h.Sum(nil))
+}
+
+// New returns a new Cache that will store files in basePath
+func New(basePath string) *Cache {
+	return &Cache{
+		d: diskv.New(diskv.Options{
+			BasePath:     basePath,
+			CacheSizeMax: 100 * 1024 * 1024, // 100MB
+		}),
+	}
+}
+
+// NewWithDiskv returns a new Cache using the provided Diskv as underlying
+// storage.
+func NewWithDiskv(d *diskv.Diskv) *Cache {
+	return &Cache{d}
+}

vendor/github.com/gregjones/httpcache/httpcache.go

@@ -0,0 +1,553 @@
+// Package httpcache provides a http.RoundTripper implementation that works as a
+// mostly RFC-compliant cache for http responses.
+//
+// It is only suitable for use as a 'private' cache (i.e. for a web-browser or an API-client
+// and not for a shared proxy).
+//
+package httpcache
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"net/http/httputil"
+	"strings"
+	"sync"
+	"time"
+)
+
+const (
+	stale = iota
+	fresh
+	transparent
+	// XFromCache is the header added to responses that are returned from the cache
+	XFromCache = "X-From-Cache"
+)
+
+// A Cache interface is used by the Transport to store and retrieve responses.
+type Cache interface {
+	// Get returns the []byte representation of a cached response and a bool
+	// set to true if the value isn't empty
+	Get(key string) (responseBytes []byte, ok bool)
+	// Set stores the []byte representation of a response against a key
+	Set(key string, responseBytes []byte)
+	// Delete removes the value associated with the key
+	Delete(key string)
+}
+
+// cacheKey returns the cache key for req.
+func cacheKey(req *http.Request) string {
+	return req.URL.String()
+}
+
+// CachedResponse returns the cached http.Response for req if present, and nil
+// otherwise.
+func CachedResponse(c Cache, req *http.Request) (resp *http.Response, err error) {
+	cachedVal, ok := c.Get(cacheKey(req))
+	if !ok {
+		return
+	}
+
+	b := bytes.NewBuffer(cachedVal)
+	return http.ReadResponse(bufio.NewReader(b), req)
+}
+
+// MemoryCache is an implemtation of Cache that stores responses in an in-memory map.
+type MemoryCache struct {
+	mu    sync.RWMutex
+	items map[string][]byte
+}
+
+// Get returns the []byte representation of the response and true if present, false if not
+func (c *MemoryCache) Get(key string) (resp []byte, ok bool) {
+	c.mu.RLock()
+	resp, ok = c.items[key]
+	c.mu.RUnlock()
+	return resp, ok
+}
+
+// Set saves response resp to the cache with key
+func (c *MemoryCache) Set(key string, resp []byte) {
+	c.mu.Lock()
+	c.items[key] = resp
+	c.mu.Unlock()
+}
+
+// Delete removes key from the cache
+func (c *MemoryCache) Delete(key string) {
+	c.mu.Lock()
+	delete(c.items, key)
+	c.mu.Unlock()
+}
+
+// NewMemoryCache returns a new Cache that will store items in an in-memory map
+func NewMemoryCache() *MemoryCache {
+	c := &MemoryCache{items: map[string][]byte{}}
+	return c
+}
+
+// Transport is an implementation of http.RoundTripper that will return values from a cache
+// where possible (avoiding a network request) and will additionally add validators (etag/if-modified-since)
+// to repeated requests allowing servers to return 304 / Not Modified
+type Transport struct {
+	// The RoundTripper interface actually used to make requests
+	// If nil, http.DefaultTransport is used
+	Transport http.RoundTripper
+	Cache     Cache
+	// If true, responses returned from the cache will be given an extra header, X-From-Cache
+	MarkCachedResponses bool
+}
+
+// NewTransport returns a new Transport with the
+// provided Cache implementation and MarkCachedResponses set to true
+func NewTransport(c Cache) *Transport {
+	return &Transport{Cache: c, MarkCachedResponses: true}
+}
+
+// Client returns an *http.Client that caches responses.
+func (t *Transport) Client() *http.Client {
+	return &http.Client{Transport: t}
+}
+
+// varyMatches will return false unless all of the cached values for the headers listed in Vary
+// match the new request
+func varyMatches(cachedResp *http.Response, req *http.Request) bool {
+	for _, header := range headerAllCommaSepValues(cachedResp.Header, "vary") {
+		header = http.CanonicalHeaderKey(header)
+		if header != "" && req.Header.Get(header) != cachedResp.Header.Get("X-Varied-"+header) {
+			return false
+		}
+	}
+	return true
+}
+
+// RoundTrip takes a Request and returns a Response
+//
+// If there is a fresh Response already in cache, then it will be returned without connecting to
+// the server.
+//
+// If there is a stale Response, then any validators it contains will be set on the new request
+// to give the server a chance to respond with NotModified. If this happens, then the cached Response
+// will be returned.
+func (t *Transport) RoundTrip(req *http.Request) (resp *http.Response, err error) {
+	cacheKey := cacheKey(req)
+	cacheable := (req.Method == "GET" || req.Method == "HEAD") && req.Header.Get("range") == ""
+	var cachedResp *http.Response
+	if cacheable {
+		cachedResp, err = CachedResponse(t.Cache, req)
+	} else {
+		// Need to invalidate an existing value
+		t.Cache.Delete(cacheKey)
+	}
+
+	transport := t.Transport
+	if transport == nil {
+		transport = http.DefaultTransport
+	}
+
+	if cacheable && cachedResp != nil && err == nil {
+		if t.MarkCachedResponses {
+			cachedResp.Header.Set(XFromCache, "1")
+		}
+
+		if varyMatches(cachedResp, req) {
+			// Can only use cached value if the new request doesn't Vary significantly
+			freshness := getFreshness(cachedResp.Header, req.Header)
+			if freshness == fresh {
+				return cachedResp, nil
+			}
+
+			if freshness == stale {
+				var req2 *http.Request
+				// Add validators if caller hasn't already done so
+				etag := cachedResp.Header.Get("etag")
+				if etag != "" && req.Header.Get("etag") == "" {
+					req2 = cloneRequest(req)
+					req2.Header.Set("if-none-match", etag)
+				}
+				lastModified := cachedResp.Header.Get("last-modified")
+				if lastModified != "" && req.Header.Get("last-modified") == "" {
+					if req2 == nil {
+						req2 = cloneRequest(req)
+					}
+					req2.Header.Set("if-modified-since", lastModified)
+				}
+				if req2 != nil {
+					req = req2
+				}
+			}
+		}
+
+		resp, err = transport.RoundTrip(req)
+		if err == nil && req.Method == "GET" && resp.StatusCode == http.StatusNotModified {
+			// Replace the 304 response with the one from cache, but update with some new headers
+			endToEndHeaders := getEndToEndHeaders(resp.Header)
+			for _, header := range endToEndHeaders {
+				cachedResp.Header[header] = resp.Header[header]
+			}
+			cachedResp.Status = fmt.Sprintf("%d %s", http.StatusOK, http.StatusText(http.StatusOK))
+			cachedResp.StatusCode = http.StatusOK
+
+			resp = cachedResp
+		} else if (err != nil || (cachedResp != nil && resp.StatusCode >= 500)) &&
+			req.Method == "GET" && canStaleOnError(cachedResp.Header, req.Header) {
+			// In case of transport failure and stale-if-error activated, returns cached content
+			// when available
+			cachedResp.Status = fmt.Sprintf("%d %s", http.StatusOK, http.StatusText(http.StatusOK))
+			cachedResp.StatusCode = http.StatusOK
+			return cachedResp, nil
+		} else {
+			if err != nil || resp.StatusCode != http.StatusOK {
+				t.Cache.Delete(cacheKey)
+			}
+			if err != nil {
+				return nil, err
+			}
+		}
+	} else {
+		reqCacheControl := parseCacheControl(req.Header)
+		if _, ok := reqCacheControl["only-if-cached"]; ok {
+			resp = newGatewayTimeoutResponse(req)
+		} else {
+			resp, err = transport.RoundTrip(req)
+			if err != nil {
+				return nil, err
+			}
+		}
+	}
+
+	if cacheable && canStore(parseCacheControl(req.Header), parseCacheControl(resp.Header)) {
+		for _, varyKey := range headerAllCommaSepValues(resp.Header, "vary") {
+			varyKey = http.CanonicalHeaderKey(varyKey)
+			fakeHeader := "X-Varied-" + varyKey
+			reqValue := req.Header.Get(varyKey)
+			if reqValue != "" {
+				resp.Header.Set(fakeHeader, reqValue)
+			}
+		}
+		switch req.Method {
+		case "GET":
+			// Delay caching until EOF is reached.
+			resp.Body = &cachingReadCloser{
+				R: resp.Body,
+				OnEOF: func(r io.Reader) {
+					resp := *resp
+					resp.Body = ioutil.NopCloser(r)
+					respBytes, err := httputil.DumpResponse(&resp, true)
+					if err == nil {
+						t.Cache.Set(cacheKey, respBytes)
+					}
+				},
+			}
+		default:
+			respBytes, err := httputil.DumpResponse(resp, true)
+			if err == nil {
+				t.Cache.Set(cacheKey, respBytes)
+			}
+		}
+	} else {
+		t.Cache.Delete(cacheKey)
+	}
+	return resp, nil
+}
+
+// ErrNoDateHeader indicates that the HTTP headers contained no Date header.
+var ErrNoDateHeader = errors.New("no Date header")
+
+// Date parses and returns the value of the Date header.
+func Date(respHeaders http.Header) (date time.Time, err error) {
+	dateHeader := respHeaders.Get("date")
+	if dateHeader == "" {
+		err = ErrNoDateHeader
+		return
+	}
+
+	return time.Parse(time.RFC1123, dateHeader)
+}
+
+type realClock struct{}
+
+func (c *realClock) since(d time.Time) time.Duration {
+	return time.Since(d)
+}
+
+type timer interface {
+	since(d time.Time) time.Duration
+}
+
+var clock timer = &realClock{}
+
+// getFreshness will return one of fresh/stale/transparent based on the cache-control
+// values of the request and the response
+//
+// fresh indicates the response can be returned
+// stale indicates that the response needs validating before it is returned
+// transparent indicates the response should not be used to fulfil the request
+//
+// Because this is only a private cache, 'public' and 'private' in cache-control aren't
+// signficant. Similarly, smax-age isn't used.
+func getFreshness(respHeaders, reqHeaders http.Header) (freshness int) {
+	respCacheControl := parseCacheControl(respHeaders)
+	reqCacheControl := parseCacheControl(reqHeaders)
+	if _, ok := reqCacheControl["no-cache"]; ok {
+		return transparent
+	}
+	if _, ok := respCacheControl["no-cache"]; ok {
+		return stale
+	}
+	if _, ok := reqCacheControl["only-if-cached"]; ok {
+		return fresh
+	}
+
+	date, err := Date(respHeaders)
+	if err != nil {
+		return stale
+	}
+	currentAge := clock.since(date)
+
+	var lifetime time.Duration
+	var zeroDuration time.Duration
+
+	// If a response includes both an Expires header and a max-age directive,
+	// the max-age directive overrides the Expires header, even if the Expires header is more restrictive.
+	if maxAge, ok := respCacheControl["max-age"]; ok {
+		lifetime, err = time.ParseDuration(maxAge + "s")
+		if err != nil {
+			lifetime = zeroDuration
+		}
+	} else {
+		expiresHeader := respHeaders.Get("Expires")
+		if expiresHeader != "" {
+			expires, err := time.Parse(time.RFC1123, expiresHeader)
+			if err != nil {
+				lifetime = zeroDuration
+			} else {
+				lifetime = expires.Sub(date)
+			}
+		}
+	}
+
+	if maxAge, ok := reqCacheControl["max-age"]; ok {
+		// the client is willing to accept a response whose age is no greater than the specified time in seconds
+		lifetime, err = time.ParseDuration(maxAge + "s")
+		if err != nil {
+			lifetime = zeroDuration
+		}
+	}
+	if minfresh, ok := reqCacheControl["min-fresh"]; ok {
+		//  the client wants a response that will still be fresh for at least the specified number of seconds.
+		minfreshDuration, err := time.ParseDuration(minfresh + "s")
+		if err == nil {
+			currentAge = time.Duration(currentAge + minfreshDuration)
+		}
+	}
+
+	if maxstale, ok := reqCacheControl["max-stale"]; ok {
+		// Indicates that the client is willing to accept a response that has exceeded its expiration time.
+		// If max-stale is assigned a value, then the client is willing to accept a response that has exceeded
+		// its expiration time by no more than the specified number of seconds.
+		// If no value is assigned to max-stale, then the client is willing to accept a stale response of any age.
+		//
+		// Responses served only because of a max-stale value are supposed to have a Warning header added to them,
+		// but that seems like a  hassle, and is it actually useful? If so, then there needs to be a different
+		// return-value available here.
+		if maxstale == "" {
+			return fresh
+		}
+		maxstaleDuration, err := time.ParseDuration(maxstale + "s")
+		if err == nil {
+			currentAge = time.Duration(currentAge - maxstaleDuration)
+		}
+	}
+
+	if lifetime > currentAge {
+		return fresh
+	}
+
+	return stale
+}
+
+// Returns true if either the request or the response includes the stale-if-error
+// cache control extension: https://tools.ietf.org/html/rfc5861
+func canStaleOnError(respHeaders, reqHeaders http.Header) bool {
+	respCacheControl := parseCacheControl(respHeaders)
+	reqCacheControl := parseCacheControl(reqHeaders)
+
+	var err error
+	lifetime := time.Duration(-1)
+
+	if staleMaxAge, ok := respCacheControl["stale-if-error"]; ok {
+		if staleMaxAge != "" {
+			lifetime, err = time.ParseDuration(staleMaxAge + "s")
+			if err != nil {
+				return false
+			}
+		} else {
+			return true
+		}
+	}
+	if staleMaxAge, ok := reqCacheControl["stale-if-error"]; ok {
+		if staleMaxAge != "" {
+			lifetime, err = time.ParseDuration(staleMaxAge + "s")
+			if err != nil {
+				return false
+			}
+		} else {
+			return true
+		}
+	}
+
+	if lifetime >= 0 {
+		date, err := Date(respHeaders)
+		if err != nil {
+			return false
+		}
+		currentAge := clock.since(date)
+		if lifetime > currentAge {
+			return true
+		}
+	}
+
+	return false
+}
+
+func getEndToEndHeaders(respHeaders http.Header) []string {
+	// These headers are always hop-by-hop
+	hopByHopHeaders := map[string]struct{}{
+		"Connection":          struct{}{},
+		"Keep-Alive":          struct{}{},
+		"Proxy-Authenticate":  struct{}{},
+		"Proxy-Authorization": struct{}{},
+		"Te":                struct{}{},
+		"Trailers":          struct{}{},
+		"Transfer-Encoding": struct{}{},
+		"Upgrade":           struct{}{},
+	}
+
+	for _, extra := range strings.Split(respHeaders.Get("connection"), ",") {
+		// any header listed in connection, if present, is also considered hop-by-hop
+		if strings.Trim(extra, " ") != "" {
+			hopByHopHeaders[http.CanonicalHeaderKey(extra)] = struct{}{}
+		}
+	}
+	endToEndHeaders := []string{}
+	for respHeader, _ := range respHeaders {
+		if _, ok := hopByHopHeaders[respHeader]; !ok {
+			endToEndHeaders = append(endToEndHeaders, respHeader)
+		}
+	}
+	return endToEndHeaders
+}
+
+func canStore(reqCacheControl, respCacheControl cacheControl) (canStore bool) {
+	if _, ok := respCacheControl["no-store"]; ok {
+		return false
+	}
+	if _, ok := reqCacheControl["no-store"]; ok {
+		return false
+	}
+	return true
+}
+
+func newGatewayTimeoutResponse(req *http.Request) *http.Response {
+	var braw bytes.Buffer
+	braw.WriteString("HTTP/1.1 504 Gateway Timeout\r\n\r\n")
+	resp, err := http.ReadResponse(bufio.NewReader(&braw), req)
+	if err != nil {
+		panic(err)
+	}
+	return resp
+}
+
+// cloneRequest returns a clone of the provided *http.Request.
+// The clone is a shallow copy of the struct and its Header map.
+// (This function copyright goauth2 authors: https://code.google.com/p/goauth2)
+func cloneRequest(r *http.Request) *http.Request {
+	// shallow copy of the struct
+	r2 := new(http.Request)
+	*r2 = *r
+	// deep copy of the Header
+	r2.Header = make(http.Header)
+	for k, s := range r.Header {
+		r2.Header[k] = s
+	}
+	return r2
+}
+
+type cacheControl map[string]string
+
+func parseCacheControl(headers http.Header) cacheControl {
+	cc := cacheControl{}
+	ccHeader := headers.Get("Cache-Control")
+	for _, part := range strings.Split(ccHeader, ",") {
+		part = strings.Trim(part, " ")
+		if part == "" {
+			continue
+		}
+		if strings.ContainsRune(part, '=') {
+			keyval := strings.Split(part, "=")
+			cc[strings.Trim(keyval[0], " ")] = strings.Trim(keyval[1], ",")
+		} else {
+			cc[part] = ""
+		}
+	}
+	return cc
+}
+
+// headerAllCommaSepValues returns all comma-separated values (each
+// with whitespace trimmed) for header name in headers. According to
+// Section 4.2 of the HTTP/1.1 spec
+// (http://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.2),
+// values from multiple occurrences of a header should be concatenated, if
+// the header's value is a comma-separated list.
+func headerAllCommaSepValues(headers http.Header, name string) []string {
+	var vals []string
+	for _, val := range headers[http.CanonicalHeaderKey(name)] {
+		fields := strings.Split(val, ",")
+		for i, f := range fields {
+			fields[i] = strings.TrimSpace(f)
+		}
+		vals = append(vals, fields...)
+	}
+	return vals
+}
+
+// cachingReadCloser is a wrapper around ReadCloser R that calls OnEOF
+// handler with a full copy of the content read from R when EOF is
+// reached.
+type cachingReadCloser struct {
+	// Underlying ReadCloser.
+	R io.ReadCloser
+	// OnEOF is called with a copy of the content of R when EOF is reached.
+	OnEOF func(io.Reader)
+
+	buf bytes.Buffer // buf stores a copy of the content of R.
+}
+
+// Read reads the next len(p) bytes from R or until R is drained. The
+// return value n is the number of bytes read. If R has no data to
+// return, err is io.EOF and OnEOF is called with a full copy of what
+// has been read so far.
+func (r *cachingReadCloser) Read(p []byte) (n int, err error) {
+	n, err = r.R.Read(p)
+	r.buf.Write(p[:n])
+	if err == io.EOF {
+		r.OnEOF(bytes.NewReader(r.buf.Bytes()))
+	}
+	return n, err
+}
+
+func (r *cachingReadCloser) Close() error {
+	return r.R.Close()
+}
+
+// NewMemoryCacheTransport returns a new Transport using the in-memory cache implementation
+func NewMemoryCacheTransport() *Transport {
+	c := NewMemoryCache()
+	t := NewTransport(c)
+	return t
+}

vendor/github.com/peterbourgon/diskv/LICENSE

@@ -0,0 +1,19 @@
+Copyright (c) 2011-2012 Peter Bourgon
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

vendor/github.com/peterbourgon/diskv/README.md

@@ -0,0 +1,141 @@
+# What is diskv?
+
+Diskv (disk-vee) is a simple, persistent key-value store written in the Go
+language. It starts with an incredibly simple API for storing arbitrary data on
+a filesystem by key, and builds several layers of performance-enhancing
+abstraction on top.  The end result is a conceptually simple, but highly
+performant, disk-backed storage system.
+
+[![Build Status][1]][2]
+
+[1]: https://drone.io/github.com/peterbourgon/diskv/status.png
+[2]: https://drone.io/github.com/peterbourgon/diskv/latest
+
+
+# Installing
+
+Install [Go 1][3], either [from source][4] or [with a prepackaged binary][5].
+Then,
+
+```bash
+$ go get github.com/peterbourgon/diskv
+```
+
+[3]: http://golang.org
+[4]: http://golang.org/doc/install/source
+[5]: http://golang.org/doc/install
+
+
+# Usage
+
+```go
+package main
+
+import (
+	"fmt"
+	"github.com/peterbourgon/diskv"
+)
+
+func main() {
+	// Simplest transform function: put all the data files into the base dir.
+	flatTransform := func(s string) []string { return []string{} }
+
+	// Initialize a new diskv store, rooted at "my-data-dir", with a 1MB cache.
+	d := diskv.New(diskv.Options{
+		BasePath:     "my-data-dir",
+		Transform:    flatTransform,
+		CacheSizeMax: 1024 * 1024,
+	})
+
+	// Write three bytes to the key "alpha".
+	key := "alpha"
+	d.Write(key, []byte{'1', '2', '3'})
+
+	// Read the value back out of the store.
+	value, _ := d.Read(key)
+	fmt.Printf("%v\n", value)
+
+	// Erase the key+value from the store (and the disk).
+	d.Erase(key)
+}
+```
+
+More complex examples can be found in the "examples" subdirectory.
+
+
+# Theory
+
+## Basic idea
+
+At its core, diskv is a map of a key (`string`) to arbitrary data (`[]byte`).
+The data is written to a single file on disk, with the same name as the key.
+The key determines where that file will be stored, via a user-provided
+`TransformFunc`, which takes a key and returns a slice (`[]string`)
+corresponding to a path list where the key file will be stored. The simplest
+TransformFunc,
+
+```go
+func SimpleTransform (key string) []string {
+    return []string{}
+}
+```
+
+will place all keys in the same, base directory. The design is inspired by
+[Redis diskstore][6]; a TransformFunc which emulates the default diskstore
+behavior is available in the content-addressable-storage example.
+
+[6]: http://groups.google.com/group/redis-db/browse_thread/thread/d444bc786689bde9?pli=1
+
+**Note** that your TransformFunc should ensure that one valid key doesn't
+transform to a subset of another valid key. That is, it shouldn't be possible
+to construct valid keys that resolve to directory names. As a concrete example,
+if your TransformFunc splits on every 3 characters, then
+
+```go
+d.Write("abcabc", val) // OK: written to <base>/abc/abc/abcabc
+d.Write("abc", val)    // Error: attempted write to <base>/abc/abc, but it's a directory
+```
+
+This will be addressed in an upcoming version of diskv.
+
+Probably the most important design principle behind diskv is that your data is
+always flatly available on the disk. diskv will never do anything that would
+prevent you from accessing, copying, backing up, or otherwise interacting with
+your data via common UNIX commandline tools.
+
+## Adding a cache
+
+An in-memory caching layer is provided by combining the BasicStore
+functionality with a simple map structure, and keeping it up-to-date as
+appropriate. Since the map structure in Go is not threadsafe, it's combined
+with a RWMutex to provide safe concurrent access.
+
+## Adding order
+
+diskv is a key-value store and therefore inherently unordered. An ordering
+system can be injected into the store by passing something which satisfies the
+diskv.Index interface. (A default implementation, using Google's
+[btree][7] package, is provided.) Basically, diskv keeps an ordered (by a
+user-provided Less function) index of the keys, which can be queried.
+
+[7]: https://github.com/google/btree
+
+## Adding compression
+
+Something which implements the diskv.Compression interface may be passed
+during store creation, so that all Writes and Reads are filtered through
+a compression/decompression pipeline. Several default implementations,
+using stdlib compression algorithms, are provided. Note that data is cached
+compressed; the cost of decompression is borne with each Read.
+
+## Streaming
+
+diskv also now provides ReadStream and WriteStream methods, to allow very large
+data to be handled efficiently.
+
+
+# Future plans
+
+ * Needs plenty of robust testing: huge datasets, etc...
+ * More thorough benchmarking
+ * Your suggestions for use-cases I haven't thought of

vendor/github.com/peterbourgon/diskv/compression.go

@@ -0,0 +1,64 @@
+package diskv
+
+import (
+	"compress/flate"
+	"compress/gzip"
+	"compress/zlib"
+	"io"
+)
+
+// Compression is an interface that Diskv uses to implement compression of
+// data. Writer takes a destination io.Writer and returns a WriteCloser that
+// compresses all data written through it. Reader takes a source io.Reader and
+// returns a ReadCloser that decompresses all data read through it. You may
+// define these methods on your own type, or use one of the NewCompression
+// helpers.
+type Compression interface {
+	Writer(dst io.Writer) (io.WriteCloser, error)
+	Reader(src io.Reader) (io.ReadCloser, error)
+}
+
+// NewGzipCompression returns a Gzip-based Compression.
+func NewGzipCompression() Compression {
+	return NewGzipCompressionLevel(flate.DefaultCompression)
+}
+
+// NewGzipCompressionLevel returns a Gzip-based Compression with the given level.
+func NewGzipCompressionLevel(level int) Compression {
+	return &genericCompression{
+		wf: func(w io.Writer) (io.WriteCloser, error) { return gzip.NewWriterLevel(w, level) },
+		rf: func(r io.Reader) (io.ReadCloser, error) { return gzip.NewReader(r) },
+	}
+}
+
+// NewZlibCompression returns a Zlib-based Compression.
+func NewZlibCompression() Compression {
+	return NewZlibCompressionLevel(flate.DefaultCompression)
+}
+
+// NewZlibCompressionLevel returns a Zlib-based Compression with the given level.
+func NewZlibCompressionLevel(level int) Compression {
+	return NewZlibCompressionLevelDict(level, nil)
+}
+
+// NewZlibCompressionLevelDict returns a Zlib-based Compression with the given
+// level, based on the given dictionary.
+func NewZlibCompressionLevelDict(level int, dict []byte) Compression {
+	return &genericCompression{
+		func(w io.Writer) (io.WriteCloser, error) { return zlib.NewWriterLevelDict(w, level, dict) },
+		func(r io.Reader) (io.ReadCloser, error) { return zlib.NewReaderDict(r, dict) },
+	}
+}
+
+type genericCompression struct {
+	wf func(w io.Writer) (io.WriteCloser, error)
+	rf func(r io.Reader) (io.ReadCloser, error)
+}
+
+func (g *genericCompression) Writer(dst io.Writer) (io.WriteCloser, error) {
+	return g.wf(dst)
+}
+
+func (g *genericCompression) Reader(src io.Reader) (io.ReadCloser, error) {
+	return g.rf(src)
+}

vendor/github.com/peterbourgon/diskv/diskv.go

@@ -0,0 +1,578 @@
+// Diskv (disk-vee) is a simple, persistent, key-value store.
+// It stores all data flatly on the filesystem.
+
+package diskv
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strings"
+	"sync"
+	"syscall"
+)
+
+const (
+	defaultBasePath             = "diskv"
+	defaultFilePerm os.FileMode = 0666
+	defaultPathPerm os.FileMode = 0777
+)
+
+var (
+	defaultTransform   = func(s string) []string { return []string{} }
+	errCanceled        = errors.New("canceled")
+	errEmptyKey        = errors.New("empty key")
+	errBadKey          = errors.New("bad key")
+	errImportDirectory = errors.New("can't import a directory")
+)
+
+// TransformFunction transforms a key into a slice of strings, with each
+// element in the slice representing a directory in the file path where the
+// key's entry will eventually be stored.
+//
+// For example, if TransformFunc transforms "abcdef" to ["ab", "cde", "f"],
+// the final location of the data file will be <basedir>/ab/cde/f/abcdef
+type TransformFunction func(s string) []string
+
+// Options define a set of properties that dictate Diskv behavior.
+// All values are optional.
+type Options struct {
+	BasePath     string
+	Transform    TransformFunction
+	CacheSizeMax uint64 // bytes
+	PathPerm     os.FileMode
+	FilePerm     os.FileMode
+
+	Index     Index
+	IndexLess LessFunction
+
+	Compression Compression
+}
+
+// Diskv implements the Diskv interface. You shouldn't construct Diskv
+// structures directly; instead, use the New constructor.
+type Diskv struct {
+	Options
+	mu        sync.RWMutex
+	cache     map[string][]byte
+	cacheSize uint64
+}
+
+// New returns an initialized Diskv structure, ready to use.
+// If the path identified by baseDir already contains data,
+// it will be accessible, but not yet cached.
+func New(o Options) *Diskv {
+	if o.BasePath == "" {
+		o.BasePath = defaultBasePath
+	}
+	if o.Transform == nil {
+		o.Transform = defaultTransform
+	}
+	if o.PathPerm == 0 {
+		o.PathPerm = defaultPathPerm
+	}
+	if o.FilePerm == 0 {
+		o.FilePerm = defaultFilePerm
+	}
+
+	d := &Diskv{
+		Options:   o,
+		cache:     map[string][]byte{},
+		cacheSize: 0,
+	}
+
+	if d.Index != nil && d.IndexLess != nil {
+		d.Index.Initialize(d.IndexLess, d.Keys(nil))
+	}
+
+	return d
+}
+
+// Write synchronously writes the key-value pair to disk, making it immediately
+// available for reads. Write relies on the filesystem to perform an eventual
+// sync to physical media. If you need stronger guarantees, see WriteStream.
+func (d *Diskv) Write(key string, val []byte) error {
+	return d.WriteStream(key, bytes.NewBuffer(val), false)
+}
+
+// WriteStream writes the data represented by the io.Reader to the disk, under
+// the provided key. If sync is true, WriteStream performs an explicit sync on
+// the file as soon as it's written.
+//
+// bytes.Buffer provides io.Reader semantics for basic data types.
+func (d *Diskv) WriteStream(key string, r io.Reader, sync bool) error {
+	if len(key) <= 0 {
+		return errEmptyKey
+	}
+
+	d.mu.Lock()
+	defer d.mu.Unlock()
+
+	return d.writeStreamWithLock(key, r, sync)
+}
+
+// writeStream does no input validation checking.
+// TODO: use atomic FS ops.
+func (d *Diskv) writeStreamWithLock(key string, r io.Reader, sync bool) error {
+	if err := d.ensurePathWithLock(key); err != nil {
+		return fmt.Errorf("ensure path: %s", err)
+	}
+
+	mode := os.O_WRONLY | os.O_CREATE | os.O_TRUNC // overwrite if exists
+	f, err := os.OpenFile(d.completeFilename(key), mode, d.FilePerm)
+	if err != nil {
+		return fmt.Errorf("open file: %s", err)
+	}
+
+	wc := io.WriteCloser(&nopWriteCloser{f})
+	if d.Compression != nil {
+		wc, err = d.Compression.Writer(f)
+		if err != nil {
+			f.Close() // error deliberately ignored
+			return fmt.Errorf("compression writer: %s", err)
+		}
+	}
+
+	if _, err := io.Copy(wc, r); err != nil {
+		f.Close() // error deliberately ignored
+		return fmt.Errorf("i/o copy: %s", err)
+	}
+
+	if err := wc.Close(); err != nil {
+		f.Close() // error deliberately ignored
+		return fmt.Errorf("compression close: %s", err)
+	}
+
+	if sync {
+		if err := f.Sync(); err != nil {
+			f.Close() // error deliberately ignored
+			return fmt.Errorf("file sync: %s", err)
+		}
+	}
+
+	if err := f.Close(); err != nil {
+		return fmt.Errorf("file close: %s", err)
+	}
+
+	if d.Index != nil {
+		d.Index.Insert(key)
+	}
+
+	d.bustCacheWithLock(key) // cache only on read
+
+	return nil
+}
+
+// Import imports the source file into diskv under the destination key. If the
+// destination key already exists, it's overwritten. If move is true, the
+// source file is removed after a successful import.
+func (d *Diskv) Import(srcFilename, dstKey string, move bool) (err error) {
+	if dstKey == "" {
+		return errEmptyKey
+	}
+
+	if fi, err := os.Stat(srcFilename); err != nil {
+		return err
+	} else if fi.IsDir() {
+		return errImportDirectory
+	}
+
+	d.mu.Lock()
+	defer d.mu.Unlock()
+
+	if err := d.ensurePathWithLock(dstKey); err != nil {
+		return fmt.Errorf("ensure path: %s", err)
+	}
+
+	if move {
+		if err := syscall.Rename(srcFilename, d.completeFilename(dstKey)); err == nil {
+			d.bustCacheWithLock(dstKey)
+			return nil
+		} else if err != syscall.EXDEV {
+			// If it failed due to being on a different device, fall back to copying
+			return err
+		}
+	}
+
+	f, err := os.Open(srcFilename)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	err = d.writeStreamWithLock(dstKey, f, false)
+	if err == nil && move {
+		err = os.Remove(srcFilename)
+	}
+	return err
+}
+
+// Read reads the key and returns the value.
+// If the key is available in the cache, Read won't touch the disk.
+// If the key is not in the cache, Read will have the side-effect of
+// lazily caching the value.
+func (d *Diskv) Read(key string) ([]byte, error) {
+	rc, err := d.ReadStream(key, false)
+	if err != nil {
+		return []byte{}, err
+	}
+	defer rc.Close()
+	return ioutil.ReadAll(rc)
+}
+
+// ReadStream reads the key and returns the value (data) as an io.ReadCloser.
+// If the value is cached from a previous read, and direct is false,
+// ReadStream will use the cached value. Otherwise, it will return a handle to
+// the file on disk, and cache the data on read.
+//
+// If direct is true, ReadStream will lazily delete any cached value for the
+// key, and return a direct handle to the file on disk.
+//
+// If compression is enabled, ReadStream taps into the io.Reader stream prior
+// to decompression, and caches the compressed data.
+func (d *Diskv) ReadStream(key string, direct bool) (io.ReadCloser, error) {
+	d.mu.RLock()
+	defer d.mu.RUnlock()
+
+	if val, ok := d.cache[key]; ok {
+		if !direct {
+			buf := bytes.NewBuffer(val)
+			if d.Compression != nil {
+				return d.Compression.Reader(buf)
+			}
+			return ioutil.NopCloser(buf), nil
+		}
+
+		go func() {
+			d.mu.Lock()
+			defer d.mu.Unlock()
+			d.uncacheWithLock(key, uint64(len(val)))
+		}()
+	}
+
+	return d.readWithRLock(key)
+}
+
+// read ignores the cache, and returns an io.ReadCloser representing the
+// decompressed data for the given key, streamed from the disk. Clients should
+// acquire a read lock on the Diskv and check the cache themselves before
+// calling read.
+func (d *Diskv) readWithRLock(key string) (io.ReadCloser, error) {
+	filename := d.completeFilename(key)
+
+	fi, err := os.Stat(filename)
+	if err != nil {
+		return nil, err
+	}
+	if fi.IsDir() {
+		return nil, os.ErrNotExist
+	}
+
+	f, err := os.Open(filename)
+	if err != nil {
+		return nil, err
+	}
+
+	var r io.Reader
+	if d.CacheSizeMax > 0 {
+		r = newSiphon(f, d, key)
+	} else {
+		r = &closingReader{f}
+	}
+
+	var rc = io.ReadCloser(ioutil.NopCloser(r))
+	if d.Compression != nil {
+		rc, err = d.Compression.Reader(r)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return rc, nil
+}
+
+// closingReader provides a Reader that automatically closes the
+// embedded ReadCloser when it reaches EOF
+type closingReader struct {
+	rc io.ReadCloser
+}
+
+func (cr closingReader) Read(p []byte) (int, error) {
+	n, err := cr.rc.Read(p)
+	if err == io.EOF {
+		if closeErr := cr.rc.Close(); closeErr != nil {
+			return n, closeErr // close must succeed for Read to succeed
+		}
+	}
+	return n, err
+}
+
+// siphon is like a TeeReader: it copies all data read through it to an
+// internal buffer, and moves that buffer to the cache at EOF.
+type siphon struct {
+	f   *os.File
+	d   *Diskv
+	key string
+	buf *bytes.Buffer
+}
+
+// newSiphon constructs a siphoning reader that represents the passed file.
+// When a successful series of reads ends in an EOF, the siphon will write
+// the buffered data to Diskv's cache under the given key.
+func newSiphon(f *os.File, d *Diskv, key string) io.Reader {
+	return &siphon{
+		f:   f,
+		d:   d,
+		key: key,
+		buf: &bytes.Buffer{},
+	}
+}
+
+// Read implements the io.Reader interface for siphon.
+func (s *siphon) Read(p []byte) (int, error) {
+	n, err := s.f.Read(p)
+
+	if err == nil {
+		return s.buf.Write(p[0:n]) // Write must succeed for Read to succeed
+	}
+
+	if err == io.EOF {
+		s.d.cacheWithoutLock(s.key, s.buf.Bytes()) // cache may fail
+		if closeErr := s.f.Close(); closeErr != nil {
+			return n, closeErr // close must succeed for Read to succeed
+		}
+		return n, err
+	}
+
+	return n, err
+}
+
+// Erase synchronously erases the given key from the disk and the cache.
+func (d *Diskv) Erase(key string) error {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+
+	d.bustCacheWithLock(key)
+
+	// erase from index
+	if d.Index != nil {
+		d.Index.Delete(key)
+	}
+
+	// erase from disk
+	filename := d.completeFilename(key)
+	if s, err := os.Stat(filename); err == nil {
+		if s.IsDir() {
+			return errBadKey
+		}
+		if err = os.Remove(filename); err != nil {
+			return err
+		}
+	} else {
+		// Return err as-is so caller can do os.IsNotExist(err).
+		return err
+	}
+
+	// clean up and return
+	d.pruneDirsWithLock(key)
+	return nil
+}
+
+// EraseAll will delete all of the data from the store, both in the cache and on
+// the disk. Note that EraseAll doesn't distinguish diskv-related data from non-
+// diskv-related data. Care should be taken to always specify a diskv base
+// directory that is exclusively for diskv data.
+func (d *Diskv) EraseAll() error {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	d.cache = make(map[string][]byte)
+	d.cacheSize = 0
+	return os.RemoveAll(d.BasePath)
+}
+
+// Has returns true if the given key exists.
+func (d *Diskv) Has(key string) bool {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+
+	if _, ok := d.cache[key]; ok {
+		return true
+	}
+
+	filename := d.completeFilename(key)
+	s, err := os.Stat(filename)
+	if err != nil {
+		return false
+	}
+	if s.IsDir() {
+		return false
+	}
+
+	return true
+}
+
+// Keys returns a channel that will yield every key accessible by the store,
+// in undefined order. If a cancel channel is provided, closing it will
+// terminate and close the keys channel.
+func (d *Diskv) Keys(cancel <-chan struct{}) <-chan string {
+	return d.KeysPrefix("", cancel)
+}
+
+// KeysPrefix returns a channel that will yield every key accessible by the
+// store with the given prefix, in undefined order. If a cancel channel is
+// provided, closing it will terminate and close the keys channel. If the
+// provided prefix is the empty string, all keys will be yielded.
+func (d *Diskv) KeysPrefix(prefix string, cancel <-chan struct{}) <-chan string {
+	var prepath string
+	if prefix == "" {
+		prepath = d.BasePath
+	} else {
+		prepath = d.pathFor(prefix)
+	}
+	c := make(chan string)
+	go func() {
+		filepath.Walk(prepath, walker(c, prefix, cancel))
+		close(c)
+	}()
+	return c
+}
+
+// walker returns a function which satisfies the filepath.WalkFunc interface.
+// It sends every non-directory file entry down the channel c.
+func walker(c chan<- string, prefix string, cancel <-chan struct{}) filepath.WalkFunc {
+	return func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+
+		if info.IsDir() || !strings.HasPrefix(info.Name(), prefix) {
+			return nil // "pass"
+		}
+
+		select {
+		case c <- info.Name():
+		case <-cancel:
+			return errCanceled
+		}
+
+		return nil
+	}
+}
+
+// pathFor returns the absolute path for location on the filesystem where the
+// data for the given key will be stored.
+func (d *Diskv) pathFor(key string) string {
+	return filepath.Join(d.BasePath, filepath.Join(d.Transform(key)...))
+}
+
+// ensurePathWithLock is a helper function that generates all necessary
+// directories on the filesystem for the given key.
+func (d *Diskv) ensurePathWithLock(key string) error {
+	return os.MkdirAll(d.pathFor(key), d.PathPerm)
+}
+
+// completeFilename returns the absolute path to the file for the given key.
+func (d *Diskv) completeFilename(key string) string {
+	return filepath.Join(d.pathFor(key), key)
+}
+
+// cacheWithLock attempts to cache the given key-value pair in the store's
+// cache. It can fail if the value is larger than the cache's maximum size.
+func (d *Diskv) cacheWithLock(key string, val []byte) error {
+	valueSize := uint64(len(val))
+	if err := d.ensureCacheSpaceWithLock(valueSize); err != nil {
+		return fmt.Errorf("%s; not caching", err)
+	}
+
+	// be very strict about memory guarantees
+	if (d.cacheSize + valueSize) > d.CacheSizeMax {
+		panic(fmt.Sprintf("failed to make room for value (%d/%d)", valueSize, d.CacheSizeMax))
+	}
+
+	d.cache[key] = val
+	d.cacheSize += valueSize
+	return nil
+}
+
+// cacheWithoutLock acquires the store's (write) mutex and calls cacheWithLock.
+func (d *Diskv) cacheWithoutLock(key string, val []byte) error {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	return d.cacheWithLock(key, val)
+}
+
+func (d *Diskv) bustCacheWithLock(key string) {
+	if val, ok := d.cache[key]; ok {
+		d.uncacheWithLock(key, uint64(len(val)))
+	}
+}
+
+func (d *Diskv) uncacheWithLock(key string, sz uint64) {
+	d.cacheSize -= sz
+	delete(d.cache, key)
+}
+
+// pruneDirsWithLock deletes empty directories in the path walk leading to the
+// key k. Typically this function is called after an Erase is made.
+func (d *Diskv) pruneDirsWithLock(key string) error {
+	pathlist := d.Transform(key)
+	for i := range pathlist {
+		dir := filepath.Join(d.BasePath, filepath.Join(pathlist[:len(pathlist)-i]...))
+
+		// thanks to Steven Blenkinsop for this snippet
+		switch fi, err := os.Stat(dir); true {
+		case err != nil:
+			return err
+		case !fi.IsDir():
+			panic(fmt.Sprintf("corrupt dirstate at %s", dir))
+		}
+
+		nlinks, err := filepath.Glob(filepath.Join(dir, "*"))
+		if err != nil {
+			return err
+		} else if len(nlinks) > 0 {
+			return nil // has subdirs -- do not prune
+		}
+		if err = os.Remove(dir); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// ensureCacheSpaceWithLock deletes entries from the cache in arbitrary order
+// until the cache has at least valueSize bytes available.
+func (d *Diskv) ensureCacheSpaceWithLock(valueSize uint64) error {
+	if valueSize > d.CacheSizeMax {
+		return fmt.Errorf("value size (%d bytes) too large for cache (%d bytes)", valueSize, d.CacheSizeMax)
+	}
+
+	safe := func() bool { return (d.cacheSize + valueSize) <= d.CacheSizeMax }
+
+	for key, val := range d.cache {
+		if safe() {
+			break
+		}
+
+		d.uncacheWithLock(key, uint64(len(val)))
+	}
+
+	if !safe() {
+		panic(fmt.Sprintf("%d bytes still won't fit in the cache! (max %d bytes)", valueSize, d.CacheSizeMax))
+	}
+
+	return nil
+}
+
+// nopWriteCloser wraps an io.Writer and provides a no-op Close method to
+// satisfy the io.WriteCloser interface.
+type nopWriteCloser struct {
+	io.Writer
+}
+
+func (wc *nopWriteCloser) Write(p []byte) (int, error) { return wc.Writer.Write(p) }
+func (wc *nopWriteCloser) Close() error                { return nil }

vendor/github.com/peterbourgon/diskv/index.go

@@ -0,0 +1,115 @@
+package diskv
+
+import (
+	"sync"
+
+	"github.com/google/btree"
+)
+
+// Index is a generic interface for things that can
+// provide an ordered list of keys.
+type Index interface {
+	Initialize(less LessFunction, keys <-chan string)
+	Insert(key string)
+	Delete(key string)
+	Keys(from string, n int) []string
+}
+
+// LessFunction is used to initialize an Index of keys in a specific order.
+type LessFunction func(string, string) bool
+
+// btreeString is a custom data type that satisfies the BTree Less interface,
+// making the strings it wraps sortable by the BTree package.
+type btreeString struct {
+	s string
+	l LessFunction
+}
+
+// Less satisfies the BTree.Less interface using the btreeString's LessFunction.
+func (s btreeString) Less(i btree.Item) bool {
+	return s.l(s.s, i.(btreeString).s)
+}
+
+// BTreeIndex is an implementation of the Index interface using google/btree.
+type BTreeIndex struct {
+	sync.RWMutex
+	LessFunction
+	*btree.BTree
+}
+
+// Initialize populates the BTree tree with data from the keys channel,
+// according to the passed less function. It's destructive to the BTreeIndex.
+func (i *BTreeIndex) Initialize(less LessFunction, keys <-chan string) {
+	i.Lock()
+	defer i.Unlock()
+	i.LessFunction = less
+	i.BTree = rebuild(less, keys)
+}
+
+// Insert inserts the given key (only) into the BTree tree.
+func (i *BTreeIndex) Insert(key string) {
+	i.Lock()
+	defer i.Unlock()
+	if i.BTree == nil || i.LessFunction == nil {
+		panic("uninitialized index")
+	}
+	i.BTree.ReplaceOrInsert(btreeString{s: key, l: i.LessFunction})
+}
+
+// Delete removes the given key (only) from the BTree tree.
+func (i *BTreeIndex) Delete(key string) {
+	i.Lock()
+	defer i.Unlock()
+	if i.BTree == nil || i.LessFunction == nil {
+		panic("uninitialized index")
+	}
+	i.BTree.Delete(btreeString{s: key, l: i.LessFunction})
+}
+
+// Keys yields a maximum of n keys in order. If the passed 'from' key is empty,
+// Keys will return the first n keys. If the passed 'from' key is non-empty, the
+// first key in the returned slice will be the key that immediately follows the
+// passed key, in key order.
+func (i *BTreeIndex) Keys(from string, n int) []string {
+	i.RLock()
+	defer i.RUnlock()
+
+	if i.BTree == nil || i.LessFunction == nil {
+		panic("uninitialized index")
+	}
+
+	if i.BTree.Len() <= 0 {
+		return []string{}
+	}
+
+	btreeFrom := btreeString{s: from, l: i.LessFunction}
+	skipFirst := true
+	if len(from) <= 0 || !i.BTree.Has(btreeFrom) {
+		// no such key, so fabricate an always-smallest item
+		btreeFrom = btreeString{s: "", l: func(string, string) bool { return true }}
+		skipFirst = false
+	}
+
+	keys := []string{}
+	iterator := func(i btree.Item) bool {
+		keys = append(keys, i.(btreeString).s)
+		return len(keys) < n
+	}
+	i.BTree.AscendGreaterOrEqual(btreeFrom, iterator)
+
+	if skipFirst && len(keys) > 0 {
+		keys = keys[1:]
+	}
+
+	return keys
+}
+
+// rebuildIndex does the work of regenerating the index
+// with the given keys.
+func rebuild(less LessFunction, keys <-chan string) *btree.BTree {
+	tree := btree.New(2)
+	for key := range keys {
+		tree.ReplaceOrInsert(btreeString{s: key, l: less})
+	}
+	return tree
+}