docs/backends/apiserver.go

142 lines
3.5 KiB
Go

package backends
import (
"encoding/json"
"fmt"
"github.com/docker/libswarm/beam"
"github.com/dotcloud/docker/api"
"github.com/dotcloud/docker/pkg/version"
"github.com/gorilla/mux"
"net"
"net/http"
)
func ApiServer() beam.Sender {
backend := beam.NewServer()
backend.OnSpawn(beam.Handler(func(ctx *beam.Message) error {
instance := beam.Task(func(in beam.Receiver, out beam.Sender) {
err := listenAndServe("tcp", "0.0.0.0:4243", out)
if err != nil {
fmt.Printf("listenAndServe: %v", err)
}
})
_, err := ctx.Ret.Send(&beam.Message{Verb: beam.Ack, Ret: instance})
return err
}))
return backend
}
type HttpApiFunc func(out beam.Sender, version version.Version, w http.ResponseWriter, r *http.Request, vars map[string]string) error
func listenAndServe(proto, addr string, out beam.Sender) error {
fmt.Println("Starting API server...")
r, err := createRouter(out)
if err != nil {
return err
}
l, err := net.Listen(proto, addr)
if err != nil {
return err
}
httpSrv := http.Server{Addr: addr, Handler: r}
return httpSrv.Serve(l)
}
func ping(out beam.Sender, version version.Version, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
_, err := w.Write([]byte{'O', 'K'})
return err
}
func getContainersJSON(out beam.Sender, version version.Version, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
if err := r.ParseForm(); err != nil {
return err
}
o := beam.Obj(out)
names, err := o.Ls()
if err != nil {
return err
}
return writeJSON(w, http.StatusOK, names)
}
func postContainersStart(out beam.Sender, version version.Version, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
if vars == nil {
return fmt.Errorf("Missing parameter")
}
// TODO: r.Body
name := vars["name"]
_, containerOut, err := beam.Obj(out).Attach(name)
container := beam.Obj(containerOut)
if err != nil {
return err
}
if err := container.Start(); err != nil {
return err
}
w.WriteHeader(http.StatusNoContent)
return nil
}
func createRouter(out beam.Sender) (*mux.Router, error) {
r := mux.NewRouter()
m := map[string]map[string]HttpApiFunc{
"GET": {
"/_ping": ping,
"/containers/json": getContainersJSON,
},
"POST": {
"/containers/{name:.*}/start": postContainersStart,
},
"DELETE": {},
"OPTIONS": {},
}
for method, routes := range m {
for route, fct := range routes {
localRoute := route
localFct := fct
localMethod := method
f := makeHttpHandler(out, localMethod, localRoute, localFct, version.Version("0.11.0"))
// add the new route
if localRoute == "" {
r.Methods(localMethod).HandlerFunc(f)
} else {
r.Path("/v{version:[0-9.]+}" + localRoute).Methods(localMethod).HandlerFunc(f)
r.Path(localRoute).Methods(localMethod).HandlerFunc(f)
}
}
}
return r, nil
}
func makeHttpHandler(out beam.Sender, localMethod string, localRoute string, handlerFunc HttpApiFunc, dockerVersion version.Version) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
// log the request
fmt.Printf("Calling %s %s\n", localMethod, localRoute)
version := version.Version(mux.Vars(r)["version"])
if version == "" {
version = api.APIVERSION
}
if err := handlerFunc(out, version, w, r, mux.Vars(r)); err != nil {
fmt.Printf("Error: %s", err)
}
}
}
func writeJSON(w http.ResponseWriter, code int, v interface{}) error {
w.Header().Set("Content-Type", "application/json")
w.WriteHeader(code)
enc := json.NewEncoder(w)
return enc.Encode(v)
}