Add datadog metrics for request and latencies per endpoint. (#164)

package.json

@@ -37,11 +37,13 @@
   "license": "ISC",
   "dependencies": {
     "@sendgrid/mail": "^7.2.1",
+    "@types/connect-datadog": "0.0.5",
     "body-parser": "^1.19.0",
     "class-transformer": "^0.3.1",
     "class-validator": "^0.12.2",
     "class-validator-jsonschema": "^2.0.2",
     "compression": "^1.7.4",
+    "connect-datadog": "0.0.9",
     "cors": "^2.8.5",
     "date-fns": "^2.16.1",
     "express": "^4.17.1",

src/app.ts

@@ -3,6 +3,7 @@ import 'module-alias/register'; // required for aliases
 import express from 'express';
 import rateLimit from 'express-rate-limit';
 import compression from 'compression';
+import connect_datadog from 'connect-datadog';
 
 import { UserRouter } from './routers/UserRouter';
 import { DocsRouter } from './routers/DocsRouter';
@@ -12,6 +13,7 @@ import { useExpressServer, useContainer as routingUseContainer } from 'routing-c
 import { controllers, ControllerContainer } from './controllers';
 
 import { loadFirebase, loadORM } from './loaders';
+import { config } from './config';
 import morgan from 'morgan';
 
 import { checkCurrentUserToken } from './decorators';
@@ -31,6 +33,15 @@ export const getExpressApp = async () => {
   app.use(express.urlencoded({ extended: true }));
   app.use(morgan('tiny'));
   app.use(limiter);
+  if (config.nodeEnv !== 'development') {
+    app.use(
+      connect_datadog({
+        method: true,
+        response_code: true,
+        tags: [config.ddMetricTag],
+      })
+    );
+  }
 
   // load controllers; maybe move into loader?
 

src/config.ts

@@ -10,6 +10,8 @@ type Config = {
   clientAppID: string;
   clientApiKey: string;
   devAuth: boolean;
+  ddMetricTag: string;
+  nodeEnv: string;
 };
 
 const {
@@ -20,6 +22,8 @@ const {
   FIREBASE_CLIENT_ID,
   FIREBASE_CLIENT_API_KEY,
   DEV_AUTH,
+  DD_METRIC_TAG,
+  NODE_ENV,
 } = process.env;
 
 const firebaseConfig: FirebaseConfig = {
@@ -34,4 +38,6 @@ export const config: Config = {
   clientAppID: FIREBASE_CLIENT_ID,
   clientApiKey: FIREBASE_CLIENT_API_KEY,
   devAuth: DEV_AUTH === 'true',
+  ddMetricTag: DD_METRIC_TAG,
+  nodeEnv: NODE_ENV,
 };