feat: add health check handler

.dockerignore

@@ -1,2 +1,3 @@
 *
+!.docker.json
 !filebrowser

Dockerfile

@@ -1,6 +1,10 @@
 FROM alpine:latest
-RUN apk --update add ca-certificates
-RUN apk --update add mailcap
+RUN apk --update add ca-certificates \
+                     mailcap \
+                     curl
+
+HEALTHCHECK --start-period=2s --interval=5s --timeout=3s \
+  CMD curl -f http://localhost/health || exit 1
 
 VOLUME /srv
 EXPOSE 80

http/http.go

@@ -36,6 +36,7 @@ func NewHandler(
 		return handle(fn, prefix, store, server)
 	}
 
+	r.HandleFunc("/health", healthHandler)
 	r.PathPrefix("/static").Handler(static)
 	r.NotFoundHandler = index
 

http/public.go

@@ -136,3 +136,8 @@ func authenticateShareRequest(r *http.Request, l *share.Link) (int, error) {
 
 	return 0, nil
 }
+
+func healthHandler(w http.ResponseWriter, _ *http.Request) {
+	w.WriteHeader(http.StatusOK)
+	_, _ = w.Write([]byte(`{"status":"OK"}`))
+}