Improve version checking to also check universe

In the future, universe will not be embedded anymore in dagger,
instead, it will be remotely vendor from `dagger/universe` repository.

To make sure that users always use the latest universe version, the
version checking now also verify that universe is not outdated.
If universe needs an update, a message is printed to standard output.

Signed-off-by: Tom Chauveau <tom.chauveau@epitech.eu>

cmd/dagger/cmd/root.go

@@ -48,7 +48,8 @@ func init() {
 		}
 	}
 	rootCmd.PersistentPostRun = func(*cobra.Command, []string) {
-		warnVersion()
+		warnDaggerVersion()
+		warnUniverseVersion()
 	}
 
 	rootCmd.AddCommand(

cmd/dagger/cmd/version.go

@@ -1,12 +1,14 @@
 package cmd
 
 import (
+	"encoding/json"
 	"fmt"
 	"io/ioutil"
 	"net/http"
 	"os"
 	"path"
 	"runtime"
+	"sort"
 	"strings"
 	"time"
 
@@ -14,22 +16,25 @@ import (
 	"github.com/mitchellh/go-homedir"
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
+	"go.dagger.io/dagger/mod"
 	"go.dagger.io/dagger/version"
 	"golang.org/x/term"
 )
 
 const (
-	versionFile = "~/.config/dagger/version-check"
-	versionURL  = "https://releases.dagger.io/dagger/latest_version"
+	versionFile     = "~/.config/dagger/version-check"
+	versionURL      = "https://releases.dagger.io/dagger/latest_version"
+	universeTagsURL = "https://api.github.com/repos/dagger/universe/tags"
 )
 
 var (
-	versionMessage = ""
+	daggerVersionMessage   = ""
+	universeVersionMessage = ""
 )
 
 var versionCmd = &cobra.Command{
 	Use:   "version",
-	Short: "Print dagger version",
+	Short: "Print dagger and universe version",
 	// Disable version hook here to avoid double version check
 	PersistentPreRun:  func(*cobra.Command, []string) {},
 	PersistentPostRun: func(*cobra.Command, []string) {},
@@ -41,6 +46,9 @@ var versionCmd = &cobra.Command{
 			runtime.GOOS, runtime.GOARCH,
 		)
 
+		// TODO Display universe version
+		// How can I retrieve it if it's not vendor ?
+
 		if check := viper.GetBool("check"); check {
 			versionFilePath, err := homedir.Expand(versionFile)
 			if err != nil {
@@ -49,15 +57,18 @@ var versionCmd = &cobra.Command{
 
 			_ = os.Remove(versionFilePath)
 			checkVersion()
-			if !warnVersion() {
+			if !warnDaggerVersion() {
 				fmt.Println("dagger is up to date.")
 			}
+			if !warnUniverseVersion() {
+				fmt.Println("universe is up to date.")
+			}
 		}
 	},
 }
 
 func init() {
-	versionCmd.Flags().Bool("check", false, "check if dagger is up to date")
+	versionCmd.Flags().Bool("check", false, "check if dagger and universe are up to date")
 
 	if err := viper.BindPFlags(versionCmd.Flags()); err != nil {
 		panic(err)
@@ -87,7 +98,7 @@ func isCheckOutdated(path string) bool {
 	return !time.Now().Before(nextCheck)
 }
 
-func getLatestVersion(currentVersion *goVersion.Version) (*goVersion.Version, error) {
+func getDaggerLatestVersion(currentVersion *goVersion.Version) (*goVersion.Version, error) {
 	req, err := http.NewRequest("GET", versionURL, nil)
 	if err != nil {
 		return nil, err
@@ -112,15 +123,113 @@ func getLatestVersion(currentVersion *goVersion.Version) (*goVersion.Version, er
 	return goVersion.NewVersion(latestVersion)
 }
 
-// Compare the binary version with the latest version online
-// Return the latest version if current is outdated
-func isVersionLatest() (string, error) {
+// Compare dagger version with the latest release online
+// Return the latest dagger version if current is outdated
+func isDaggerVersionLatest() (string, error) {
 	currentVersion, err := goVersion.NewVersion(version.Version)
 	if err != nil {
 		return "", err
 	}
 
-	latestVersion, err := getLatestVersion(currentVersion)
+	latestVersion, err := getDaggerLatestVersion(currentVersion)
+	if err != nil {
+		return "", err
+	}
+
+	if currentVersion.LessThan(latestVersion) {
+		return latestVersion.String(), nil
+	}
+	return "", nil
+}
+
+// Call https://api.github.com/repos/dagger/universe/tags
+func listUniverseTags() ([]string, error) {
+	req, err := http.NewRequest("GET", universeTagsURL, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return nil, err
+	}
+
+	defer resp.Body.Close()
+	data, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	var tagsDTO []struct {
+		Name string `json:"name"`
+	}
+
+	err = json.Unmarshal(data, &tagsDTO)
+	if err != nil {
+		return nil, err
+	}
+
+	// Reduce DTO to simple string array
+	tags := []string{}
+	for _, tag := range tagsDTO {
+		tags = append(tags, tag.Name)
+	}
+
+	return tags, nil
+}
+
+func getUniverseLatestVersion() (*goVersion.Version, error) {
+	tags, err := listUniverseTags()
+	if err != nil {
+		return nil, err
+	}
+
+	// Get latest available version
+	constraint, err := goVersion.NewConstraint(mod.UniverseVersionConstraint)
+	if err != nil {
+		return nil, err
+	}
+
+	// Retrieve the latest supported universe version
+	var versions []*goVersion.Version
+	for _, tag := range tags {
+		if !strings.HasPrefix(tag, "v") {
+			continue
+		}
+
+		v, err := goVersion.NewVersion(tag)
+		if err != nil {
+			continue
+		}
+
+		if constraint.Check(v) {
+			versions = append(versions, v)
+		}
+	}
+
+	if len(versions) == 0 {
+		return nil, fmt.Errorf("universe repository has no version matching the required version")
+	}
+
+	sort.Sort(sort.Reverse(goVersion.Collection(versions)))
+	return versions[0], nil
+}
+
+func getUniverseCurrentVersion() (*goVersion.Version, error) {
+	// TODO Should be replaced with the current universe version
+	// How I can fetch it
+	return goVersion.NewVersion("0.1.0")
+}
+
+// Compare the universe version with the latest version online
+// Return the latest universe version if the current is outdated
+func isUniverseVersionLatest() (string, error) {
+	currentVersion, err := getUniverseCurrentVersion()
+	if err != nil {
+		return "", err
+	}
+
+	latestVersion, err := getUniverseLatestVersion()
 	if err != nil {
 		return "", err
 	}
@@ -154,14 +263,24 @@ func checkVersion() {
 		return
 	}
 
-	// Check timestamp
-	latestVersion, err := isVersionLatest()
+	// Check version
+	universeLatestVersion, err := isUniverseVersionLatest()
 	if err != nil {
 		return
 	}
 
-	if latestVersion != "" {
-		versionMessage = fmt.Sprintf("\nA new version is available (%s), please go to https://github.com/dagger/dagger/doc/install.md for instructions.", latestVersion)
+	if universeLatestVersion != "" {
+		universeVersionMessage = fmt.Sprintf("A new version of universe is available (%s), please run 'dagger mod get github.com/dagger/universe/stdlib'", universeLatestVersion)
+	}
+
+	// Check timestamp
+	daggerLatestVersion, err := isDaggerVersionLatest()
+	if err != nil {
+		return
+	}
+
+	if daggerLatestVersion != "" {
+		daggerVersionMessage = fmt.Sprintf("\nA new version of dagger is available (%s), please go to https://github.com/dagger/dagger/doc/install.md for instructions.", daggerLatestVersion)
 	}
 
 	// Update check timestamps file
@@ -169,8 +288,8 @@ func checkVersion() {
 	ioutil.WriteFile(path.Join(versionFilePath), []byte(now), 0600)
 }
 
-func warnVersion() bool {
-	if versionMessage == "" {
+func warnDaggerVersion() bool {
+	if daggerVersionMessage == "" {
 		return false
 	}
 
@@ -185,6 +304,15 @@ func warnVersion() bool {
 	}
 
 	// Print default message
-	fmt.Println(versionMessage)
+	fmt.Println(daggerVersionMessage)
+	return true
+}
+
+func warnUniverseVersion() bool {
+	if universeVersionMessage == "" {
+		return false
+	}
+
+	fmt.Println(universeVersionMessage)
 	return true
 }