From 6ac673056bd2bfbba8971e02a533ae238897c220 Mon Sep 17 00:00:00 2001
From: Michael Mayer <michael@photoprism.app>
Date: Fri, 9 Feb 2024 08:42:08 +0100
Subject: [PATCH] Server: Add "GET /health" handler so clients can perform
 health checks

Signed-off-by: Michael Mayer <michael@photoprism.app>
---
 internal/server/start.go | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/internal/server/start.go b/internal/server/start.go
index f0af51d96..72b7394c9 100644
--- a/internal/server/start.go
+++ b/internal/server/start.go
@@ -15,6 +15,7 @@ import (
 	"github.com/gin-gonic/gin"
 
 	"github.com/photoprism/photoprism/internal/config"
+	"github.com/photoprism/photoprism/pkg/header"
 )
 
 // Start the REST API server using the configuration provided
@@ -27,14 +28,14 @@ func Start(ctx context.Context, conf *config.Config) {
 
 	start := time.Now()
 
-	// Set HTTP server mode.
+	// Set web server mode.
 	if conf.HttpMode() != "" {
 		gin.SetMode(conf.HttpMode())
 	} else if conf.Debug() == false {
 		gin.SetMode(gin.ReleaseMode)
 	}
 
-	// Create new HTTP router engine without standard middleware.
+	// Create new router engine without standard middleware.
 	router := gin.New()
 
 	// Set proxy addresses from which headers related to the client and protocol can be trusted
@@ -56,6 +57,7 @@ func Start(ctx context.Context, conf *config.Config) {
 				".png", ".gif", ".jpeg", ".jpg", ".webp", ".mp3", ".mp4", ".zip", ".gz",
 			}),
 			gzip.WithExcludedPaths([]string{
+				conf.BaseUri("/health"),
 				conf.BaseUri(config.ApiUri + "/t"),
 				conf.BaseUri(config.ApiUri + "/folders/t"),
 				conf.BaseUri(config.ApiUri + "/zip"),
@@ -79,14 +81,21 @@ func Start(ctx context.Context, conf *config.Config) {
 	// Find and load templates.
 	router.LoadHTMLFiles(conf.TemplateFiles()...)
 
-	// Register HTTP route handlers.
+	// Register application routes.
 	registerRoutes(router, conf)
 
+	// Register "GET /health" route so clients can perform health checks.
+	router.GET(conf.BaseUri("/health"), func(c *gin.Context) {
+		c.Header(header.CacheControl, header.CacheControlNoStore)
+		c.Header(header.AccessControlAllowOrigin, header.Any)
+		c.String(http.StatusOK, "OK")
+	})
+
+	// Start web server.
 	var tlsErr error
 	var tlsManager *autocert.Manager
 	var server *http.Server
 
-	// Start HTTP server.
 	if unixSocket := conf.HttpSocket(); unixSocket != "" {
 		var listener net.Listener
 		var unixAddr *net.UnixAddr
@@ -144,7 +153,7 @@ func Start(ctx context.Context, conf *config.Config) {
 		}
 	}
 
-	// Graceful HTTP server shutdown.
+	// Graceful web server shutdown.
 	<-ctx.Done()
 	log.Info("server: shutting down")
 	err := server.Close()