Move code to pkg

pkg/version/version.go

@@ -0,0 +1,96 @@
+package version
+
+import (
+	"context"
+	"net/http"
+	"net/url"
+
+	"github.com/containous/mux"
+	"github.com/containous/traefik/pkg/log"
+	"github.com/google/go-github/github"
+	goversion "github.com/hashicorp/go-version"
+	"github.com/unrolled/render"
+)
+
+var (
+	// Version holds the current version of traefik.
+	Version = "dev"
+	// Codename holds the current version codename of traefik.
+	Codename = "cheddar" // beta cheese
+	// BuildDate holds the build date of traefik.
+	BuildDate = "I don't remember exactly"
+)
+
+// Handler expose version routes
+type Handler struct{}
+
+var (
+	templatesRenderer = render.New(render.Options{
+		Directory: "nowhere",
+	})
+)
+
+// Append adds version routes on a router.
+func (v Handler) Append(router *mux.Router) {
+	router.Methods(http.MethodGet).Path("/api/version").
+		HandlerFunc(func(response http.ResponseWriter, request *http.Request) {
+			v := struct {
+				Version  string
+				Codename string
+			}{
+				Version:  Version,
+				Codename: Codename,
+			}
+
+			if err := templatesRenderer.JSON(response, http.StatusOK, v); err != nil {
+				log.Error(err)
+			}
+		})
+}
+
+// CheckNewVersion checks if a new version is available
+func CheckNewVersion() {
+	if Version == "dev" {
+		return
+	}
+	client := github.NewClient(nil)
+	updateURL, err := url.Parse("https://update.traefik.io")
+	if err != nil {
+		log.Warnf("Error checking new version: %s", err)
+		return
+	}
+	client.BaseURL = updateURL
+	releases, resp, err := client.Repositories.ListReleases(context.Background(), "containous", "traefik", nil)
+	if err != nil {
+		log.Warnf("Error checking new version: %s", err)
+		return
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		log.Warnf("Error checking new version: status=%s", resp.Status)
+		return
+	}
+
+	currentVersion, err := goversion.NewVersion(Version)
+	if err != nil {
+		log.Warnf("Error checking new version: %s", err)
+		return
+	}
+
+	for _, release := range releases {
+		releaseVersion, err := goversion.NewVersion(*release.TagName)
+		if err != nil {
+			log.Warnf("Error checking new version: %s", err)
+			return
+		}
+
+		if len(currentVersion.Prerelease()) == 0 && len(releaseVersion.Prerelease()) > 0 {
+			continue
+		}
+
+		if releaseVersion.GreaterThan(currentVersion) {
+			log.Warnf("A new release has been found: %s. Please consider updating.", releaseVersion.String())
+			return
+		}
+	}
+}