adding go files and rsc

adding go files and rsc

Dockerfile

@@ -0,0 +1,17 @@
+# Start from a Debian image with the latest version of Go installed
+# and a workspace (GOPATH) configured at /go.
+FROM golang:alpine
+
+# Copy the local package files to the container's workspace.
+ADD /outyet.go /go/src/outyet/
+
+# Build the outyet command inside the container.
+# (You may fetch or manage dependencies here,
+# either manually or with a tool like "godep".)
+RUN go install outyet
+
+# Run the outyet command by default when the container starts.
+ENTRYPOINT /go/bin/outyet
+
+# Document that the service listens on port 8080.
+EXPOSE 8080

outyet.go

@@ -0,0 +1,159 @@
+/*
+Copyright 2014 Google Inc.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+     http://www.apache.org/licenses/LICENSE-2.0
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// outyet is a web server that announces whether or not a particular Go version
+// has been tagged.
+package main
+
+import (
+	"expvar"
+	"flag"
+	"fmt"
+	"html/template"
+	"log"
+	"net"
+	"net/http"
+	"sync"
+	"time"
+)
+
+// Command-line flags.
+var (
+	httpAddr   = flag.String("http", ":8081", "Listen address")
+	pollPeriod = flag.Duration("poll", 5*time.Second, "Poll period")
+	version    = flag.String("version", "1.9.0", "Go version")
+	iphost     = flag.String("iphost", "127.0.0.1", "IP Host")
+)
+
+const baseChangeURL = "https://go.googlesource.com/go/+/"
+
+func main() {
+	flag.Parse()
+	ifaces, err := net.Interfaces()
+	var ipcheck net.IP
+	if err != nil {
+		log.Print(err)
+	}
+
+	// handle err
+	for _, i := range ifaces {
+		addrs, err := i.Addrs()
+		if err != nil {
+			log.Print(err)
+		}
+		// handle err
+		for _, addr := range addrs {
+			switch v := addr.(type) {
+			case *net.IPNet:
+				ipcheck = v.IP
+			case *net.IPAddr:
+				ipcheck = v.IP
+			}
+			// process IP address
+		}
+	}
+	iphost = flag.String("Ip Host", ipcheck.String(), "IP Host")
+	changeURL := fmt.Sprintf("%sgo%s", baseChangeURL, *iphost)
+	http.Handle("/", NewServer(*iphost, changeURL, *pollPeriod))
+	log.Fatal(http.ListenAndServe(*httpAddr, nil))
+}
+
+// Exported variables for monitoring the server.
+// These are exported via HTTP as a JSON object at /debug/vars.
+var (
+	hitCount       = expvar.NewInt("hitCount")
+	pollCount      = expvar.NewInt("pollCount")
+	pollError      = expvar.NewString("pollError")
+	pollErrorCount = expvar.NewInt("pollErrorCount")
+)
+
+// Server implements the outyet server.
+// It serves the user interface (it's an http.Handler)
+// and polls the remote repository for changes.
+type Server struct {
+	version string
+	url     string
+	period  time.Duration
+
+	mu  sync.RWMutex // protects the yes variable
+	yes bool
+}
+
+// NewServer returns an initialized outyet server.
+func NewServer(version, url string, period time.Duration) *Server {
+	s := &Server{version: version, url: url, period: period}
+	go s.poll()
+	return s
+}
+
+// poll polls the change URL for the specified period until the tag exists.
+// Then it sets the Server's yes field true and exits.
+func (s *Server) poll() {
+	for !isTagged(s.url) {
+		pollSleep(s.period)
+	}
+	s.mu.Lock()
+	s.yes = true
+	s.mu.Unlock()
+	pollDone()
+}
+
+// Hooks that may be overridden for integration tests.
+var (
+	pollSleep = time.Sleep
+	pollDone  = func() {}
+)
+
+// isTagged makes an HTTP HEAD request to the given URL and reports whether it
+// returned a 200 OK response.
+func isTagged(url string) bool {
+	pollCount.Add(1)
+	r, err := http.Head(url)
+	if err != nil {
+		log.Print(err)
+		pollError.Set(err.Error())
+		pollErrorCount.Add(1)
+		return false
+	}
+	return r.StatusCode == http.StatusOK
+}
+
+// ServeHTTP implements the HTTP user interface.
+func (s *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	hitCount.Add(1)
+	s.mu.RLock()
+	data := struct {
+		URL     string
+		Version string
+		Yes     bool
+	}{
+		s.url,
+		s.version,
+		s.yes,
+	}
+	s.mu.RUnlock()
+	err := tmpl.Execute(w, data)
+	if err != nil {
+		log.Print(err)
+	}
+}
+
+// tmpl is the HTML template that drives the user interface.
+var tmpl = template.Must(template.New("tmpl").Parse(`
+<!DOCTYPE html><html><body><center>
+	<h1 style="color:blue">Playing with Kubernetes & Katacoda!</h1>
+	<h2 style="color:green">Your server IP: {{.Version}}</h2>
+	<h3 style="color:green">Rolling version [1.0-k8s}</h3>	
+	<img src="https://raw.githubusercontent.com/twogg-git/k8s-intro/master/kubernetes_katacoda.png" alt="Kubernetes & Katacoda" style="width:400px;height:200px;">
+</center></body></html>
+`))