Merge pull request #20 from remind101/updater

Add flag to update the binary.

Makefile

@@ -4,4 +4,4 @@ cmd:
 	godep go build -o build/deploy ./cmd/deploy
 
 release:
-	goxc -bc="linux,darwin" -d build -pv="0.0.3"
+	./scripts/release $(VERSION)

deploy.go

@@ -69,6 +69,10 @@ var flags = []cli.Flag{
 		Name:  "quiet, q",
 		Usage: "Silence any output to STDOUT.",
 	},
+	cli.BoolFlag{
+		Name:  "update, u",
+		Usage: "Update the binary",
+	},
 }
 
 var ProtectedEnvironments = map[string]bool{
@@ -83,6 +87,16 @@ func NewApp() *cli.App {
 	app.Usage = Usage
 	app.Flags = flags
 	app.Action = func(c *cli.Context) {
+		if c.Bool("update") {
+			updater := NewUpdater()
+			if err := updater.Update(); err != nil {
+				fmt.Println(err)
+				os.Exit(-1)
+			} else {
+				os.Exit(0)
+			}
+		}
+
 		if err := RunDeploy(c); err != nil {
 			msg := err.Error()
 			if err, ok := err.(*github.ErrorResponse); ok {

scripts/release

@@ -0,0 +1,11 @@
+#!/bin/bash
+
+if [ -z "$1" ]; then
+    echo "need version number. make release VERSION=0.0.3"
+    exit
+fi
+
+goxc -bc="linux,darwin" -d build -pv="$1" -tasks-=package
+
+find $(dirname $0)/../build/$1/* -type d -exec mv -n -- {}/deploy {}_deploy \;
+rm -R -- $(dirname $0)/../build/$1/*/

updater.go

@@ -0,0 +1,78 @@
+package deploy
+
+import (
+	"fmt"
+	"runtime"
+	"strings"
+
+	"github.com/remind101/deploy/Godeps/_workspace/src/github.com/inconshreveable/go-update"
+	"github.com/remind101/deploy/Godeps/_workspace/src/github.com/octokit/go-octokit/octokit"
+)
+
+const GitHubHost = "github.com"
+
+type Updater struct {
+	Host           string
+	CurrentVersion string
+}
+
+func NewUpdater() *Updater {
+	version := Version
+	return &Updater{
+		Host:           GitHubHost,
+		CurrentVersion: version,
+	}
+}
+
+func (updater *Updater) Update() (err error) {
+	releaseName, version := updater.latestReleaseNameAndVersion()
+
+	if version == "" {
+		fmt.Println("There is no newer version of Deploy available.")
+		return
+	}
+
+	if version == updater.CurrentVersion {
+		fmt.Printf("You're already on the latest version: %s\n", version)
+	} else {
+		err = updater.updateTo(releaseName, version)
+	}
+
+	return
+}
+
+func (updater *Updater) updateTo(releaseName, version string) (err error) {
+	downloadURL := fmt.Sprintf("https://%s/remind101/deploy/releases/download/%s/%s_%s_deploy", updater.Host, releaseName, runtime.GOOS, runtime.GOARCH)
+
+	fmt.Printf("Downloading %s...", version)
+	err, _ = update.New().FromUrl(downloadURL)
+	if err != nil {
+		fmt.Printf("Update failed: %v\n", err)
+	}
+
+	return
+}
+
+func (updater *Updater) latestReleaseNameAndVersion() (name, version string) {
+	client := octokit.NewClient(nil)
+
+	url, err := octokit.ReleasesURL.Expand(octokit.M{"owner": "remind101", "repo": "deploy"})
+	if err != nil {
+		return
+	}
+
+	releases, result := client.Releases(url).All()
+	if result.HasError() {
+		err = fmt.Errorf("Error getting Deploy release: %s", result.Err)
+		return
+	}
+
+	if len(releases) == 0 {
+		err = fmt.Errorf("No Deploy release is available")
+		return
+	}
+
+	name = releases[0].TagName
+	version = strings.TrimPrefix(name, "v")
+	return
+}