Rudimentary HTTP GUI

gui.go

@@ -0,0 +1,106 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
+	"mime"
+	"net/http"
+	"path/filepath"
+	"bitbucket.org/tebeka/nrsc"
+
+	"github.com/codegangsta/martini"
+)
+
+func startGUI(addr string, m *Model) {
+	router := martini.NewRouter()
+	router.Get("/rest/version", restGetVersion)
+	router.Get("/rest/model", restGetModel)
+	router.Get("/rest/connections", restGetConnections)
+	router.Get("/rest/config", restGetConfig)
+	router.Get("/rest/need", restGetNeed)
+
+	go func() {
+		mr := martini.New()
+		mr.Use(nrscStatic("gui"))
+		mr.Use(martini.Recovery())
+		mr.Action(router.Handle)
+		mr.Map(m)
+		http.ListenAndServe(addr, mr)
+	}()
+}
+
+func restGetVersion() string {
+	return Version
+}
+
+func restGetModel(m *Model, w http.ResponseWriter) {
+	var res = make(map[string]interface{})
+
+	res["globalFiles"], res["globalDeleted"], res["globalBytes"] = m.GlobalSize()
+	res["localFiles"], res["localDeleted"], res["localBytes"] = m.LocalSize()
+	files, total := m.NeedFiles()
+	res["needFiles"], res["needBytes"] = len(files), total
+
+	w.Header().Set("Content-Type", "application/json")
+	json.NewEncoder(w).Encode(res)
+}
+
+func restGetConnections(m *Model, w http.ResponseWriter) {
+	var res = m.ConnectionStats()
+	w.Header().Set("Content-Type", "application/json")
+	json.NewEncoder(w).Encode(res)
+}
+
+func restGetConfig(w http.ResponseWriter) {
+	var res = make(map[string]interface{})
+	res["repository"] = config.OptionMap("repository")
+	res["nodes"] = config.OptionMap("nodes")
+	w.Header().Set("Content-Type", "application/json")
+	json.NewEncoder(w).Encode(res)
+}
+
+func restGetNeed(m *Model, w http.ResponseWriter) {
+	files, _ := m.NeedFiles()
+	if files == nil {
+		// We don't want the empty list to serialize as "null\n"
+		files = make([]FileInfo, 0)
+	}
+	w.Header().Set("Content-Type", "application/json")
+	json.NewEncoder(w).Encode(files)
+}
+
+func nrscStatic(path string) interface{} {
+	if err := nrsc.Initialize(); err != nil {
+		panic("Unable to initialize nrsc: " + err.Error())
+	}
+	return func(res http.ResponseWriter, req *http.Request, log *log.Logger) {
+		file := req.URL.Path
+
+		// nrsc expects there not to be a leading slash
+		if file[0] == '/' {
+			file = file[1:]
+		}
+
+		f := nrsc.Get(file)
+		if f == nil {
+			return
+		}
+
+		rdr, err := f.Open()
+		if err != nil {
+			http.Error(res, "Internal Server Error", http.StatusInternalServerError)
+		}
+		defer rdr.Close()
+
+		mtype := mime.TypeByExtension(filepath.Ext(req.URL.Path))
+		if len(mtype) != 0 {
+			res.Header().Set("Content-Type", mtype)
+		}
+		res.Header().Set("Content-Size", fmt.Sprintf("%d", f.Size()))
+		res.Header().Set("Last-Modified", f.ModTime().UTC().Format(http.TimeFormat))
+
+		io.Copy(res, rdr)
+	}
+}