Merge pull request #1 from gianarb/feature/event-stream

Event stream

api/events.go

@@ -0,0 +1,22 @@
+package api
+
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/Sirupsen/logrus"
+)
+
+func Events(eventChannel chan *logrus.Entry) func(w http.ResponseWriter, r *http.Request) {
+	return func(w http.ResponseWriter, r *http.Request) {
+		logrus.Info("New events")
+		formatter := &logrus.JSONFormatter{}
+		flusher, _ := w.(http.Flusher)
+		for {
+			e := <-eventChannel
+			b, _ := formatter.Format(e)
+			fmt.Fprintf(w, string(b))
+			flusher.Flush()
+		}
+	}
+}

api/router.go

@@ -1,13 +1,15 @@
 package api
 
 import (
+	"github.com/Sirupsen/logrus"
 	"github.com/gianarb/orbiter/core"
 	"github.com/gorilla/mux"
 )
 
-func GetRouter(core core.Core) *mux.Router {
+func GetRouter(core core.Core, eventChannel chan *logrus.Entry) *mux.Router {
 	r := mux.NewRouter()
 	r.HandleFunc("/handle/{autoscaler_name}/{service_name}", Handle(core.Autoscalers)).Methods("POST")
 	r.HandleFunc("/health", Health()).Methods("GET")
+	r.HandleFunc("/events", Events(eventChannel)).Methods("GET")
 	return r
 }

cmd/daemon.go

@@ -15,6 +15,7 @@ import (
 )
 
 type DaemonCmd struct {
+	EventChannel chan *logrus.Entry
 }
 
 func (c *DaemonCmd) Run(args []string) int {
@@ -51,7 +52,7 @@ func (c *DaemonCmd) Run(args []string) int {
 		logrus.Info("Stopping and cleaning. Bye!")
 		os.Exit(0)
 	}()
-	router := api.GetRouter(core)
+	router := api.GetRouter(core, c.EventChannel)
 	logrus.Infof("API Server run on port %s", port)
 	http.ListenAndServe(port, router)
 	return 0

main.go

@@ -3,17 +3,22 @@ package main
 import (
 	"os"
 
+	"github.com/Sirupsen/logrus"
 	"github.com/gianarb/orbiter/cmd"
+	"github.com/gianarb/orbiter/utils/hook"
 	"github.com/mitchellh/cli"
 )
 
 func main() {
+	eventChannel := make(chan *logrus.Entry)
+	logrus.AddHook(hook.NewChannelHook(eventChannel))
+
 	c := cli.NewCLI("orbiter", "0.0.0")
 	c.Args = os.Args[1:]
 
 	c.Commands = map[string]cli.CommandFactory{
 		"daemon": func() (cli.Command, error) {
-			return &cmd.DaemonCmd{}, nil
+			return &cmd.DaemonCmd{eventChannel}, nil
 		},
 	}
 

utils/hook/channel.go

@@ -0,0 +1,26 @@
+package hook
+
+import "github.com/Sirupsen/logrus"
+
+type Channel struct {
+	c chan *logrus.Entry
+}
+
+func NewChannelHook(cc chan *logrus.Entry) Channel {
+	return Channel{
+		c: cc,
+	}
+}
+
+func (channel Channel) Levels() []logrus.Level {
+	return logrus.AllLevels
+}
+
+func (channel Channel) Fire(entry *logrus.Entry) error {
+	select {
+	case channel.c <- entry:
+	default:
+	}
+
+	return nil
+}