view: Add /version endpoint

This allows to get the server version via HTTP. The output of `git
describe --dirty --always` and a line break is returned together with
HTTP 200.

If the server build contains no version information an error message and
HTTP 404 is returned.

2 files changed, 19 insertions, 0 deletions

diff --git a/main.go b/main.go
index 2c39239..50cfce5 100644
--- a/main.go
+++ b/main.go
@@ -59,6 +59,8 @@ func startServer(addr string) *http.Server {
 	r.PathPrefix("/static/").
 		Handler(http.StripPrefix("/static/", http.FileServer(http.FS(static))))
 
+	r.HandleFunc("/version", view.VersionRead(gitDescribe)).Methods(`GET`)
+
 	r.HandleFunc("/recipes", view.RecipesRead).Methods(`GET`)
 
 	r.HandleFunc("/recipe", controller.RecipeCreate).Methods(`POST`)
diff --git a/view/version.go b/view/version.go
new file mode 100644
index 0000000..faf91b1
--- /dev/null
+++ b/view/version.go
@@ -0,0 +1,17 @@
+package view
+
+import (
+	"fmt"
+	"net/http"
+)
+
+func VersionRead(version string) func(http.ResponseWriter, *http.Request) {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if version == "" {
+			http.Error(w, "This build has no version information", http.StatusNotFound)
+			return
+		}
+
+		fmt.Fprintln(w, version)
+	}
+}