Add health endpoint

build.gradle

@@ -21,11 +21,12 @@ license {
 
 repositories {
     mavenCentral()
+    maven { url 'https://nexus.lucko.me/repository/maven-snapshots/' }
 }
 
 dependencies {
     compileOnly 'org.slf4j:slf4j-api:1.7.36'
-    compileOnly 'net.luckperms:api:5.4'
+    compileOnly 'net.luckperms:api:5.5-20231022.200451-2'
     implementation 'io.javalin:javalin:4.6.4'
     implementation 'io.javalin:javalin-openapi:4.6.4'
 }

src/main/java/me/lucko/luckperms/extension/rest/RestServer.java

@@ -44,6 +44,7 @@
 import me.lucko.luckperms.extension.rest.util.SwaggerUi;
 import net.luckperms.api.LuckPerms;
 import net.luckperms.api.messaging.MessagingService;
+import net.luckperms.api.platform.Health;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -115,6 +116,11 @@ private void setupErrorHandlers(Javalin app) {
     private void setupRoutes(Javalin app, LuckPerms luckPerms) {
         app.get("/", ctx -> ctx.redirect("/docs/swagger-ui"));
 
+        app.get("health", ctx -> {
+            Health health = luckPerms.runHealthCheck();
+            ctx.status(health.isHealthy() ? HttpCode.OK : HttpCode.SERVICE_UNAVAILABLE).json(health);
+        });
+
         MessagingService messagingService = luckPerms.getMessagingService().orElse(StubMessagingService.INSTANCE);
 
         UserController userController = new UserController(luckPerms.getUserManager(), luckPerms.getTrackManager(), messagingService, this.objectMapper);

src/main/java/me/lucko/luckperms/extension/rest/bind/HealthSerializer.java

@@ -0,0 +1,51 @@
+/*
+ * This file is part of LuckPerms, licensed under the MIT License.
+ *
+ *  Copyright (c) lucko (Luck) <[email protected]>
+ *  Copyright (c) contributors
+ *
+ *  Permission is hereby granted, free of charge, to any person obtaining a copy
+ *  of this software and associated documentation files (the "Software"), to deal
+ *  in the Software without restriction, including without limitation the rights
+ *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ *  copies of the Software, and to permit persons to whom the Software is
+ *  furnished to do so, subject to the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be included in all
+ *  copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ *  SOFTWARE.
+ */
+
+package me.lucko.luckperms.extension.rest.bind;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.JsonSerializer;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import net.luckperms.api.platform.Health;
+
+import java.io.IOException;
+import java.util.Map;
+
+public class HealthSerializer extends JsonSerializer<Health> {
+
+    @Override
+    public void serialize(Health value, JsonGenerator gen, SerializerProvider serializers) throws IOException {
+        gen.writePOJO(Model.from(value));
+    }
+
+    record Model(boolean healthy, Map<String, Object> details) {
+        static Model from(Health health) {
+            return new Model(
+                    health.isHealthy(),
+                    health.getDetails()
+            );
+        }
+    }
+}

src/main/java/me/lucko/luckperms/extension/rest/util/CustomObjectMapper.java

@@ -34,6 +34,7 @@
 import me.lucko.luckperms.extension.rest.bind.ContextSetSerializer;
 import me.lucko.luckperms.extension.rest.bind.DemotionResultSerializer;
 import me.lucko.luckperms.extension.rest.bind.GroupSerializer;
+import me.lucko.luckperms.extension.rest.bind.HealthSerializer;
 import me.lucko.luckperms.extension.rest.bind.MetadataSerializer;
 import me.lucko.luckperms.extension.rest.bind.NodeDeserializer;
 import me.lucko.luckperms.extension.rest.bind.NodeSerializer;
@@ -46,6 +47,7 @@
 import net.luckperms.api.model.group.Group;
 import net.luckperms.api.model.user.User;
 import net.luckperms.api.node.Node;
+import net.luckperms.api.platform.Health;
 import net.luckperms.api.query.QueryOptions;
 import net.luckperms.api.track.DemotionResult;
 import net.luckperms.api.track.PromotionResult;
@@ -64,6 +66,7 @@ public CustomObjectMapper() {
         module.addSerializer(ContextSet.class, new ContextSetSerializer());
         module.addSerializer(DemotionResult.class, new DemotionResultSerializer());
         module.addSerializer(Group.class, new GroupSerializer());
+        module.addSerializer(Health.class, new HealthSerializer());
         module.addSerializer(CachedMetaData.class, new MetadataSerializer());
         module.addDeserializer(Node.class, new NodeDeserializer());
         module.addSerializer(Node.class, new NodeSerializer());

src/main/resources/luckperms-openapi.yml

@@ -18,6 +18,8 @@ tags:
     description: API methods for LuckPerms groups.
   - name: Actions
     description: API methods for LuckPerms actions.
+  - name: Misc
+    description: Miscellaneous API methods.
 paths:
   /user:
     get:
@@ -1128,6 +1130,39 @@ paths:
       description: Submit a new action to the action logger.
       tags:
         - Actions
+  /health:
+    get:
+      summary: Get the current health status of the app
+      operationId: get-health
+      responses:
+        '200':
+          description: Ok
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Health'
+              examples:
+                example-1:
+                  value:
+                    health: true
+                    details:
+                      storageConnected: true
+                      storagePing: 15
+        '503':
+          description: Service Unavailable
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Health'
+              examples:
+                example-1:
+                  value:
+                    health: false
+                    details:
+                      reason: storage is disconnected
+      description: Returns the current health status of the app
+      tags:
+        - Misc
 components:
   schemas:
     Node:
@@ -1574,6 +1609,20 @@ components:
         - replace_existing_if_duration_longer
         - none
       default: 'none'
+    Health:
+      title: Health
+      type: object
+      description: The health status of the app
+      properties:
+        health:
+          type: boolean
+          description: if the app is healthy
+        details:
+          type: object
+          description: extra information about the healthcheck result
+      required:
+        - health
+        - details
   securitySchemes:
     apikey:
       type: http