Merge pull request #17 from ReconfigureIO/feature/self-update

Add update command to let reco self-update

Author: CampGareth

Makefile

@@ -17,6 +17,7 @@ LDFLAGS := -X 'main.version=$(VERSION)' \
            -X 'main.buildTime=$(BUILDTIME)' \
            -X 'main.builder=$(BUILDER)' \
            -X 'main.goversion=$(GOVERSION)' \
+           -X 'main.target=$(TARGET)' \
            -X 'github.com/ReconfigureIO/reco.alternativePlatformServer=$(API_SERVER)'
 CODEBUILD_NAME := "sample-snap-builder"
 GO_EXTENSION :=
@@ -77,8 +78,7 @@ dist/%-${VERSION}-${TARGET}.zip: build/${TARGET}/%${GO_EXTENSION} | dist
 packages: $(PKG_TARGETS)
 
 install: $(TARGETS)
-	cp ${TARGETS} /usr/local/bin
-
+	cp ${TARGETS} /go/bin
 clean:
 	rm -rf ./dist $(TARGETS) ./build
 

cmd/reco/main.go

@@ -8,6 +8,7 @@ func main() {
 	cmd.BuildInfo.BuildTime = buildTime
 	cmd.BuildInfo.Builder = builder
 	cmd.BuildInfo.GoVersion = goversion
+	cmd.BuildInfo.Target = target
 
 	// execute
 	cmd.Execute()
@@ -18,4 +19,5 @@ var (
 	buildTime string
 	builder   string
 	goversion string
+	target    string
 )

cmd/update.go

@@ -0,0 +1,143 @@
+package cmd
+
+import (
+	"archive/zip"
+	"bytes"
+	"context"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"net/http"
+
+	"github.com/ReconfigureIO/cobra"
+	"github.com/ReconfigureIO/go-update"
+	"github.com/ReconfigureIO/reco/logger"
+	"github.com/google/go-github/github"
+)
+
+const (
+	recoDownloadAddress = "https://s3.amazonaws.com/reconfigure.io/reco/releases/"
+)
+
+// updateCmd represents the update command
+var (
+	updateCmd = &cobra.Command{
+		Use:   "update",
+		Short: "Update reco to the latest version",
+		Run:   updateHandler,
+	}
+
+	justDoIt bool
+)
+
+func init() {
+	RootCmd.AddCommand(updateCmd)
+	updateCmd.PersistentFlags().BoolVar(&justDoIt, "just-do-it", justDoIt, "Download and apply update without user interaction")
+}
+
+func updateHandler(cmd *cobra.Command, args []string) {
+	if BuildInfo.Version == "" {
+		logger.Std.Println("reco version: untracked dev build")
+		logger.Std.Println("Cannot automatically update from this version")
+		return
+	}
+	logger.Std.Println("You are using reco ", BuildInfo.Version)
+	latest, err := latestRelease(github.NewClient(nil))
+	if err != nil {
+		logger.Std.Println("Could not retrieve latest verion info from Github: ", err)
+		return
+	} else {
+		logger.Std.Println("The latest release is reco ", latest)
+	}
+
+	if justDoIt {
+		err = UpgradeTo(latest, BuildInfo.Target)
+		if err != nil {
+			exitWithError(err)
+		} else {
+			return
+		}
+	}
+
+	if latest != BuildInfo.Version {
+		logger.Std.Println("Would you like to upgrade? (Y/N)")
+		upgrade := askForConfirmation()
+		if upgrade == true {
+			if err := UpgradeTo(latest, BuildInfo.Target); err != nil {
+				exitWithError(err)
+			}
+		}
+
+	} else {
+		logger.Std.Println("You are using the latest version")
+		return
+	}
+
+	return
+}
+
+// latestRelease gets the version number of the latest reco release
+func latestRelease(client *github.Client) (string, error) {
+	release, _, err := client.Repositories.GetLatestRelease(context.Background(), "ReconfigureIO", "reco")
+	if err != nil {
+		return "", err
+	}
+	return *release.TagName, nil
+}
+
+func askForConfirmation() bool {
+	var response string
+	_, err := fmt.Scanln(&response)
+	if err != nil {
+		log.Fatal(err)
+	}
+	okayResponses := []string{"y", "Y", "yes", "Yes", "YES"}
+	nokayResponses := []string{"n", "N", "no", "No", "NO"}
+	if containsString(okayResponses, response) {
+		return true
+	} else if containsString(nokayResponses, response) {
+		return false
+	} else {
+		fmt.Println("Please type yes or no and then press enter:")
+		return askForConfirmation()
+	}
+}
+
+func posString(slice []string, element string) int {
+	for index, elem := range slice {
+		if elem == element {
+			return index
+		}
+	}
+	return -1
+}
+
+// containsString returns true iff slice contains element
+func containsString(slice []string, element string) bool {
+	return !(posString(slice, element) == -1)
+}
+
+func UpgradeTo(version string, platform string) error {
+	downloadURL := recoDownloadAddress + "reco-" + version + "-" + platform + ".zip"
+	resp, err := http.Get(downloadURL)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+	zipFile, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return err
+	}
+	unzip, err := zip.NewReader(bytes.NewReader(zipFile), int64(len(zipFile)))
+	if err != nil {
+		return err
+	}
+	newReco, err := unzip.File[0].Open()
+	err = update.Apply(newReco, update.Options{})
+	if err != nil {
+		logger.Std.Println("Error occured during self-update")
+		return err
+	}
+	logger.Std.Println("Self-update successful")
+	return err
+}

cmd/update_test.go

@@ -0,0 +1,19 @@
+package cmd
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/google/go-github/github"
+)
+
+func TestLatestRelease(t *testing.T) {
+	latest, err := latestRelease(github.NewClient(nil))
+	if err != nil {
+		t.Error(err)
+	}
+	if latest == "" {
+		t.Error("Returned string is empty")
+	}
+	fmt.Println(latest)
+}

cmd/version.go

@@ -1,14 +1,14 @@
 package cmd
 
 import (
-	"github.com/ReconfigureIO/reco/logger"
 	"github.com/ReconfigureIO/cobra"
+	"github.com/ReconfigureIO/reco/logger"
 )
 
 // BuildInfo is the build information of reco binary. This is
 // set at build time by ldflags.
 var BuildInfo struct {
-	Version, BuildTime, Builder, GoVersion string
+	Version, BuildTime, Builder, GoVersion, Target string
 }
 
 // versionCmd represents the version command