commands/http: Moved HTTP RPC handler into commands/http

commands/http/handler.go

+package http
+
+import (
+	"io"
+	"net/http"
+	"strings"
+
+	cmds "github.com/jbenet/go-ipfs/commands"
+	"github.com/jbenet/go-ipfs/core/commands"
+)
+
+type Handler struct{}
+
+// TODO: store ipfsnode context
+
+func (i Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	path := strings.Split(r.URL.Path, "/")[3:]
+	opts := getOptions(r)
+
+	// TODO: get args
+
+	// ensure the requested command exists, otherwise 404
+	_, err := commands.Root.Get(path)
+	if err != nil {
+		w.WriteHeader(http.StatusNotFound)
+		w.Write([]byte("404 page not found"))
+		return
+	}
+
+	// build the Request and call the command
+	req := cmds.NewRequest(path, opts, nil, nil)
+	res := commands.Root.Call(req)
+
+	// set the Content-Type based on res output
+	if _, ok := res.Value().(io.Reader); ok {
+		// TODO: set based on actual Content-Type of file
+		w.Header().Set("Content-Type", "application/octet-stream")
+	} else {
+		// TODO: get proper MIME type for encoding from multicodec lib
+		enc, _ := req.Option(cmds.EncShort)
+		w.Header().Set("Content-Type", "application/"+enc.(string))
+	}
+
+	// if response contains an error, write an HTTP error status code
+	if e := res.Error(); e != nil {
+		if e.Code == cmds.ErrClient {
+			w.WriteHeader(http.StatusBadRequest)
+		} else {
+			w.WriteHeader(http.StatusInternalServerError)
+		}
+	}
+
+	_, err = io.Copy(w, res)
+	if err != nil {
+		w.WriteHeader(http.StatusInternalServerError)
+		w.Header().Set("Content-Type", "text/plain")
+		w.Write([]byte(err.Error()))
+	}
+}
+
+// getOptions returns the command options in the given HTTP request
+// (from the querystring and request body)
+func getOptions(r *http.Request) map[string]interface{} {
+	opts := make(map[string]interface{})
+
+	query := r.URL.Query()
+	for k, v := range query {
+		opts[k] = v[0]
+	}
+
+	// TODO: get more options from request body (formdata, json, etc)
+
+	_, short := opts[cmds.EncShort]
+	_, long := opts[cmds.EncLong]
+	if !short && !long {
+		opts[cmds.EncShort] = cmds.JSON
+	}
+
+	return opts
+}