Introduce Lightship health checks (#57)

* Set lightship signal status on mongoose connection

* Add unified topology option to mongoose connection

* Remove incompatible mongoose options

* Register lightship shutdown handler

* Update deployment manifest with readiness and liveness probes

config/deployment.yml

@@ -101,29 +101,29 @@ spec:
                   name: mern-auth-boilerplate-config
           image: <IMAGE>
           imagePullPolicy: IfNotPresent
+          readinessProbe:
+            httpGet:
+              path: /ready
+              port: 9000
+            failureThreshold: 1
+            initialDelaySeconds: 5
+            periodSeconds: 5
+            successThreshold: 1
+            timeoutSeconds: 5
           livenessProbe:
-            failureThreshold: 3
             httpGet:
-              path: /
-              port: http
-              scheme: HTTP
-            periodSeconds: 10
+              path: /live
+              port: 9000
+            failureThreshold: 3
+            initialDelaySeconds: 5
+            periodSeconds: 30
             successThreshold: 1
-            timeoutSeconds: 1
+            timeoutSeconds: 5
           name: nodeapp
           ports:
             - containerPort: 5000
               name: http
               protocol: TCP
-          readinessProbe:
-            failureThreshold: 3
-            httpGet:
-              path: /
-              port: http
-              scheme: HTTP
-            periodSeconds: 10
-            successThreshold: 1
-            timeoutSeconds: 1
           resources: {}
           securityContext: {}
           terminationMessagePath: /dev/termination-log

package.json

@@ -47,6 +47,7 @@
     "is-empty": "^1.2.0",
     "js-cookie": "^2.2.1",
     "jsonwebtoken": "^8.5.1",
+    "lightship": "^6.1.0",
     "lodash": "^4.17.15",
     "moment": "^2.24.0",
     "mongoose": "^5.8.6",
@@ -103,4 +104,4 @@
     "webpack-dev-middleware": "^1.9.0",
     "webpack-dev-server": "^3.10.1"
   }
-}
+}

server/config/db.js

@@ -13,8 +13,7 @@ module.exports = {
 		"admin"}${MONGO_REPLICASET ? `&replicaSet=${MONGO_REPLICASET}` : ""}`,
 	options: {
 		connectTimeoutMS: 10000,
-		reconnectTries: 10,
-		reconnectInterval: 500,
-		useNewUrlParser: true
+		useNewUrlParser: true,
+		useUnifiedTopology: true
 	}
 };

server/index.js

@@ -3,6 +3,7 @@ const bodyParser = require("body-parser");
 const cookieParser = require("cookie-parser");
 const express = require("express");
 const mongoose = require("mongoose");
+const { createLightship } = require("lightship");
 const { ApolloServer } = require("apollo-server-express");
 const router = express.Router();
 
@@ -19,12 +20,26 @@ const typeDefs = require("./src/types");
 
 const PORT = process.env.PORT || 5000;
 
+const app = express();
+
+const lightship = createLightship();
+lightship.registerShutdownHandler(() => {
+	server.close();
+});
+
 mongoose
 	.connect(db.url, db.options)
-	.then(() => console.log("MongoDB successfully connected"))
-	.catch(err => console.log(err));
-
-const app = express();
+	.then(() => {
+		console.log("MongoDB successfully connected");
+		mongoose.connection.on("disconnected", () => {
+			lightship.signalNotReady();
+		});
+		lightship.signalReady();
+	})
+	.catch(err => {
+		console.log(err);
+		lightship.signalNotReady();
+	});
 
 process.env.NODE_ENV !== "production"
 	? require("./init.dev")(app)