use same HTTP client as dockerengine

Signed-off-by: Victor Vieux <vieux@docker.com>

api/handlers.go

@@ -124,9 +124,9 @@ func getImages(c *context, w http.ResponseWriter, r *http.Request) {
 	names := r.Form["names"]
 
 	// Create a map of engine address to the list of images it holds.
-	engineImages := make(map[string][]*cluster.Image)
+	engineImages := make(map[*cluster.Engine][]*cluster.Image)
 	for _, image := range c.cluster.Images() {
-		engineImages[image.Engine.Addr] = append(engineImages[image.Engine.Addr], image)
+		engineImages[image.Engine] = append(engineImages[image.Engine], image)
 	}
 
 	// Look for an engine that has all the images we need.
@@ -146,7 +146,7 @@ func getImages(c *context, w http.ResponseWriter, r *http.Request) {
 
 		// If the engine has all images, stop our search here.
 		if matchedImages == len(names) {
-			proxy(c.tlsConfig, engine, w, r)
+			proxy(engine, w, r)
 			return
 		}
 	}
@@ -462,7 +462,11 @@ func getContainerJSON(c *context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	client, scheme := newClientAndScheme(c.tlsConfig)
+	client, scheme := container.Engine.HTTPClientAndScheme()
+	if client == nil {
+		httpError(w, "Cannot connect to docker engine", http.StatusInternalServerError)
+		return
+	}
 
 	resp, err := client.Get(scheme + "://" + container.Engine.Addr + "/containers/" + container.Id + "/json")
 	container.Engine.CheckConnectionErr(err)
@@ -767,7 +771,11 @@ func postContainersExec(c *context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	client, scheme := newClientAndScheme(c.tlsConfig)
+	client, scheme := container.Engine.HTTPClientAndScheme()
+	if client == nil {
+		httpError(w, "Cannot connect to docker engine", http.StatusInternalServerError)
+		return
+	}
 
 	resp, err := client.Post(scheme+"://"+container.Engine.Addr+"/containers/"+container.Id+"/exec", "application/json", r.Body)
 	container.Engine.CheckConnectionErr(err)
@@ -931,7 +939,7 @@ func proxyNetworkDisconnect(c *context, w http.ResponseWriter, r *http.Request)
 	}
 
 	// request is forwarded to the container's address
-	err := proxyAsync(c.tlsConfig, engine.Addr, w, r, cb)
+	err := proxyAsync(engine, w, r, cb)
 	engine.CheckConnectionErr(err)
 	if err != nil {
 		httpError(w, err.Error(), http.StatusNotFound)
@@ -974,7 +982,7 @@ func proxyNetworkConnect(c *context, w http.ResponseWriter, r *http.Request) {
 	}
 
 	// request is forwarded to the container's address
-	err := proxyAsync(c.tlsConfig, container.Engine.Addr, w, r, cb)
+	err := proxyAsync(container.Engine, w, r, cb)
 	container.Engine.CheckConnectionErr(err)
 	if err != nil {
 		httpError(w, err.Error(), http.StatusNotFound)
@@ -997,7 +1005,7 @@ func proxyContainer(c *context, w http.ResponseWriter, r *http.Request) {
 		r.URL.Path = strings.Replace(r.URL.Path, name, container.Id, 1)
 	}
 
-	err = proxy(c.tlsConfig, container.Engine.Addr, w, r)
+	err = proxy(container.Engine, w, r)
 	container.Engine.CheckConnectionErr(err)
 	if err != nil {
 		httpError(w, err.Error(), http.StatusInternalServerError)
@@ -1025,7 +1033,7 @@ func proxyContainerAndForceRefresh(c *context, w http.ResponseWriter, r *http.Re
 		container.Refresh()
 	}
 
-	err = proxyAsync(c.tlsConfig, container.Engine.Addr, w, r, cb)
+	err = proxyAsync(container.Engine, w, r, cb)
 	container.Engine.CheckConnectionErr(err)
 	if err != nil {
 		httpError(w, err.Error(), http.StatusInternalServerError)
@@ -1037,7 +1045,7 @@ func proxyImage(c *context, w http.ResponseWriter, r *http.Request) {
 	name := mux.Vars(r)["name"]
 
 	if image := c.cluster.Image(name); image != nil {
-		err := proxy(c.tlsConfig, image.Engine.Addr, w, r)
+		err := proxy(image.Engine, w, r)
 		image.Engine.CheckConnectionErr(err)
 		return
 	}
@@ -1051,7 +1059,7 @@ func proxyImageGet(c *context, w http.ResponseWriter, r *http.Request) {
 	for _, image := range c.cluster.Images() {
 		if len(strings.SplitN(name, ":", 2)) == 2 && image.Match(name, true) ||
 			len(strings.SplitN(name, ":", 2)) == 1 && image.Match(name, false) {
-			err := proxy(c.tlsConfig, image.Engine.Addr, w, r)
+			err := proxy(image.Engine, w, r)
 			image.Engine.CheckConnectionErr(err)
 			return
 		}
@@ -1075,7 +1083,7 @@ func proxyImagePush(c *context, w http.ResponseWriter, r *http.Request) {
 	for _, image := range c.cluster.Images() {
 		if tag != "" && image.Match(name, true) ||
 			tag == "" && image.Match(name, false) {
-			err := proxy(c.tlsConfig, image.Engine.Addr, w, r)
+			err := proxy(image.Engine, w, r)
 			image.Engine.CheckConnectionErr(err)
 			return
 		}
@@ -1120,7 +1128,7 @@ func proxyRandom(c *context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	err = proxy(c.tlsConfig, engine.Addr, w, r)
+	err = proxy(engine, w, r)
 	engine.CheckConnectionErr(err)
 	if err != nil {
 		httpError(w, err.Error(), http.StatusInternalServerError)
@@ -1159,7 +1167,7 @@ func postCommit(c *context, w http.ResponseWriter, r *http.Request) {
 	}
 
 	// proxy commit request to the right node
-	err = proxyAsync(c.tlsConfig, container.Engine.Addr, w, r, cb)
+	err = proxyAsync(container.Engine, w, r, cb)
 	container.Engine.CheckConnectionErr(err)
 	if err != nil {
 		httpError(w, err.Error(), http.StatusInternalServerError)

api/utils.go

@@ -54,12 +54,6 @@ func sendErrorJSONMessage(w io.Writer, errorCode int, errorMessage string) {
 
 	json.NewEncoder(w).Encode(message)
 }
-func newClientAndScheme(tlsConfig *tls.Config) (*http.Client, string) {
-	if tlsConfig != nil {
-		return &http.Client{Transport: &http.Transport{TLSClientConfig: tlsConfig}}, "https"
-	}
-	return &http.Client{}, "http"
-}
 
 func getContainerFromVars(c *context, vars map[string]string) (string, *cluster.Container, error) {
 	if name, ok := vars["name"]; ok {
@@ -102,14 +96,14 @@ func closeIdleConnections(client *http.Client) {
 	}
 }
 
-func proxyAsync(tlsConfig *tls.Config, addr string, w http.ResponseWriter, r *http.Request, callback func(*http.Response)) error {
+func proxyAsync(engine *cluster.Engine, w http.ResponseWriter, r *http.Request, callback func(*http.Response)) error {
-	// Use a new client for each request
-	client, scheme := newClientAndScheme(tlsConfig)
 	// RequestURI may not be sent to client
 	r.RequestURI = ""
 
+	client, scheme := engine.HTTPClientAndScheme()
+
 	r.URL.Scheme = scheme
-	r.URL.Host = addr
+	r.URL.Host = engine.Addr
 
 	log.WithFields(log.Fields{"method": r.Method, "url": r.URL}).Debug("Proxy request")
 	resp, err := client.Do(r)
@@ -132,8 +126,8 @@ func proxyAsync(tlsConfig *tls.Config, addr string, w http.ResponseWriter, r *ht
 	return nil
 }
 
-func proxy(tlsConfig *tls.Config, addr string, w http.ResponseWriter, r *http.Request) error {
+func proxy(engine *cluster.Engine, w http.ResponseWriter, r *http.Request) error {
-	return proxyAsync(tlsConfig, addr, w, r, nil)
+	return proxyAsync(engine, w, r, nil)
 }
 
 type tlsClientConn struct {

cluster/engine.go

@@ -8,6 +8,7 @@ import (
 	"math"
 	"math/rand"
 	"net"
+	"net/http"
 	"strings"
 	"sync"
 	"time"
@@ -131,6 +132,14 @@ func NewEngine(addr string, overcommitRatio float64, opts *EngineOpts) *Engine {
 	return e
 }
 
+// HTTPClientAndScheme returns the underlying HTTPClient and the scheme used by the engine
+func (e *Engine) HTTPClientAndScheme() (*http.Client, string) {
+	if dc, ok := e.client.(*dockerclient.DockerClient); ok {
+		return dc.HTTPClient, dc.URL.Scheme
+	}
+	return nil, ""
+}
+
 // Connect will initialize a connection to the Docker daemon running on the
 // host, gather machine specs (memory, cpu, ...) and monitor state changes.
 func (e *Engine) Connect(config *tls.Config) error {