Add health check endpoint (#18465)

* chore: add health check endpoint

docs: update document about health check

fix: fix up Sqlite3 ping. current ping will success even if the db file is missing

fix: do not expose privacy information in output field

* refactor: remove HealthChecker struct

* Added `/api/healthz` to install routes.

This was needed for using /api/healthz endpoint in Docker healthchecks,
otherwise, Docker would never become healthy if using healthz endpoint
and users would not be able to complete the installation of Gitea.

* Update modules/cache/cache.go

* fine tune

* Remove unnecessary test code. Now there are 2 routes for installation (and maybe more in future)

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: 6543 <6543@obermui.de>
Co-authored-by: Marcos de Oliveira <marcossantos@furb.br>

1 files changed, 25 insertions, 12 deletions

diff --git a/modules/cache/cache.go b/modules/cache/cache.go
index 0198f8da73..fd32aa153b 100644
--- a/modules/cache/cache.go
+++ b/modules/cache/cache.go
@@ -5,6 +5,7 @@
 package cache
 
 import (
+	"errors"
 	"fmt"
 	"strconv"
 
@@ -34,25 +35,37 @@ func NewContext() error {
 		if conn, err = newCache(setting.CacheService.Cache); err != nil {
 			return err
 		}
-		const testKey = "__gitea_cache_test"
-		const testVal = "test-value"
-		if err = conn.Put(testKey, testVal, 10); err != nil {
+		if err = Ping(); err != nil {
 			return err
 		}
-		val := conn.Get(testKey)
-		if valStr, ok := val.(string); !ok || valStr != testVal {
-			// If the cache is full, the Get may not read the expected value stored by Put.
-			// Since we have checked that Put can success, so we just show a warning here, do not return an error to panic.
-			log.Warn("cache (adapter:%s, config:%s) doesn't seem to work correctly, set test value '%v' but get '%v'",
-				setting.CacheService.Cache.Adapter, setting.CacheService.Cache.Conn,
-				testVal, val,
-			)
-		}
 	}
 
 	return err
 }
 
+// Ping checks if the cache service works or not, it not, it returns an error
+func Ping() error {
+	if conn == nil {
+		return errors.New("cache not available")
+	}
+	var err error
+	const testKey = "__gitea_cache_test"
+	const testVal = "test-value"
+	if err = conn.Put(testKey, testVal, 10); err != nil {
+		return err
+	}
+	val := conn.Get(testKey)
+	if valStr, ok := val.(string); !ok || valStr != testVal {
+		// If the cache is full, the Get may not read the expected value stored by Put.
+		// Since we have checked that Put can success, so we just show a warning here, do not return an error to panic.
+		log.Warn("cache (adapter:%s, config:%s) doesn't seem to work correctly, set test value '%v' but get '%v'",
+			setting.CacheService.Cache.Adapter, setting.CacheService.Cache.Conn,
+			testVal, val,
+		)
+	}
+	return nil
+}
+
 // GetCache returns the currently configured cache
 func GetCache() mc.Cache {
 	return conn