From 83c9fbaea42afa61d50ef33446c07766820b8eea Mon Sep 17 00:00:00 2001
From: Munkh-Orgil <munkhorgil@live.com>
Date: Wed, 24 Jun 2020 15:24:07 +0800
Subject: [PATCH 1/3] add health check status for services

---
 src/db/connection.ts | 15 +++++++++++++++
 src/index.ts         | 29 +++++++++++++++++++++++++----
 src/messageBroker.ts | 20 +++++++++++++++++++-
 src/redisClient.ts   | 16 ++++++++++++++++
 4 files changed, 75 insertions(+), 5 deletions(-)

diff --git a/src/db/connection.ts b/src/db/connection.ts
index 63ef718ab..d413e193c 100644
--- a/src/db/connection.ts
+++ b/src/db/connection.ts
@@ -46,6 +46,21 @@ export function disconnect() {
   return mongoose.connection.close();
 }
 
+/**
+ * Health check status
+ */
+export const mongoStatus = () => {
+  return new Promise((resolve, reject) => {
+    mongoose.connection.db.admin().ping((err, result) => {
+      if (err) {
+        return reject(err);
+      }
+
+      return resolve(result);
+    });
+  });
+};
+
 const schema = makeExecutableSchema({
   typeDefs,
   resolvers,
diff --git a/src/index.ts b/src/index.ts
index 184d8f674..3852a766c 100755
--- a/src/index.ts
+++ b/src/index.ts
@@ -21,14 +21,14 @@ import {
   readFileRequest,
   registerOnboardHistory,
 } from './data/utils';
-import { connect } from './db/connection';
+import { connect, mongoStatus } from './db/connection';
 import { debugBase, debugExternalApi, debugInit } from './debuggers';
 import { identifyCustomer, trackCustomEvent, trackViewPageEvent, updateCustomerProperty } from './events';
-import { initConsumer } from './messageBroker';
+import { initConsumer, rabbitMQStatus } from './messageBroker';
 import { importer, uploader } from './middlewares/fileMiddleware';
 import userMiddleware from './middlewares/userMiddleware';
 import widgetsMiddleware from './middlewares/widgetsMiddleware';
-import { initRedis } from './redisClient';
+import { initRedis, redisStatus } from './redisClient';
 import init from './startup';
 
 // load environment variables
@@ -126,7 +126,28 @@ app.get('/download-template', async (req: any, res) => {
 });
 
 // for health check
-app.get('/status', async (_req, res) => {
+app.get('/status', async (_req, res, next) => {
+  try {
+    await mongoStatus();
+  } catch (e) {
+    debugBase('MongoDB is not running');
+    next(e);
+  }
+
+  try {
+    await redisStatus();
+  } catch (e) {
+    debugBase('Redis is not running');
+    next(e);
+  }
+
+  try {
+    await rabbitMQStatus();
+  } catch (e) {
+    debugBase('RabbitMQ is not running');
+    next(e);
+  }
+
   res.end('ok');
 });
 
diff --git a/src/messageBroker.ts b/src/messageBroker.ts
index 719a132b3..e2ef231a8 100644
--- a/src/messageBroker.ts
+++ b/src/messageBroker.ts
@@ -1,4 +1,4 @@
-import * as amqplib from 'amqplib';
+import amqplib from 'amqplib';
 import * as dotenv from 'dotenv';
 import * as uuid from 'uuid';
 import {
@@ -162,3 +162,21 @@ export const initConsumer = async () => {
     }
   });
 };
+
+/**
+ * Health check rabbitMQ
+ */
+export const rabbitMQStatus = async () => {
+  return new Promise((resolve, reject) => {
+    // tslint:disable-next-line:no-submodule-imports
+    import('amqplib/callback_api').then(amqp => {
+      amqp.connect(RABBITMQ_HOST, error => {
+        if (error) {
+          return reject(error);
+        }
+
+        return resolve('ok');
+      });
+    });
+  });
+};
diff --git a/src/redisClient.ts b/src/redisClient.ts
index c13d45e77..88d330624 100644
--- a/src/redisClient.ts
+++ b/src/redisClient.ts
@@ -129,3 +129,19 @@ export const removeFromArray = (setKey: string, setMember: string) => {
     });
   });
 };
+
+/**
+ * Health check status
+ * retryStrategy - get response immediately
+ */
+export const redisStatus = () => {
+  return new Promise((resolve, reject) => {
+    client.ping((error, result) => {
+      if (error) {
+        return reject(error);
+      }
+
+      return resolve(result);
+    });
+  });
+};

From 23729cadfdf021561b653d7a722fe60972080dcc Mon Sep 17 00:00:00 2001
From: Munkh-Orgil <munkhorgil@live.com>
Date: Wed, 24 Jun 2020 15:25:47 +0800
Subject: [PATCH 2/3] fix promise

---
 src/messageBroker.ts | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/src/messageBroker.ts b/src/messageBroker.ts
index e2ef231a8..07572b302 100644
--- a/src/messageBroker.ts
+++ b/src/messageBroker.ts
@@ -170,13 +170,15 @@ export const rabbitMQStatus = async () => {
   return new Promise((resolve, reject) => {
     // tslint:disable-next-line:no-submodule-imports
     import('amqplib/callback_api').then(amqp => {
-      amqp.connect(RABBITMQ_HOST, error => {
-        if (error) {
-          return reject(error);
-        }
+      amqp
+        .connect(RABBITMQ_HOST, error => {
+          if (error) {
+            return reject(error);
+          }
 
-        return resolve('ok');
-      });
+          return resolve('ok');
+        })
+        .catch(e => reject(e));
     });
   });
 };

From 25e03132eb534c37ef525216be907d985add10e3 Mon Sep 17 00:00:00 2001
From: Munkh-Orgil <munkhorgil@live.com>
Date: Wed, 24 Jun 2020 15:26:43 +0800
Subject: [PATCH 3/3] fix catch in rabbitMQ

---
 src/messageBroker.ts | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/messageBroker.ts b/src/messageBroker.ts
index 07572b302..34be64d9d 100644
--- a/src/messageBroker.ts
+++ b/src/messageBroker.ts
@@ -169,16 +169,16 @@ export const initConsumer = async () => {
 export const rabbitMQStatus = async () => {
   return new Promise((resolve, reject) => {
     // tslint:disable-next-line:no-submodule-imports
-    import('amqplib/callback_api').then(amqp => {
-      amqp
-        .connect(RABBITMQ_HOST, error => {
+    import('amqplib/callback_api')
+      .then(amqp => {
+        amqp.connect(RABBITMQ_HOST, error => {
           if (error) {
             return reject(error);
           }
 
           return resolve('ok');
-        })
-        .catch(e => reject(e));
-    });
+        });
+      })
+      .catch(e => reject(e));
   });
 };