From 841117aaf4b7a56d3753b1d1fbead7a8e4ce887e Mon Sep 17 00:00:00 2001
From: Sergey Peshkov <serge1peshcoff@mail.ru>
Date: Sun, 22 Sep 2019 19:47:22 +0300
Subject: [PATCH] fix(metrics): fix endpoint metric name

---
 lib/endpoints_metrics.js | 35 +++++++++++++++++++++++++++++++++++
 lib/server.js            |  3 +++
 package.json             |  1 +
 test/api/metrics.test.js | 13 ++++++++++++-
 4 files changed, 51 insertions(+), 1 deletion(-)
 create mode 100644 lib/endpoints_metrics.js

diff --git a/lib/endpoints_metrics.js b/lib/endpoints_metrics.js
new file mode 100644
index 00000000..e77f3030
--- /dev/null
+++ b/lib/endpoints_metrics.js
@@ -0,0 +1,35 @@
+const onFinished = require('on-finished');
+const {
+    Counter,
+    Registry
+} = require('prom-client');
+
+const endpointsRegistry = new Registry();
+const responseCounter = new Counter({
+    name: 'discounts_requests_total',
+    help: 'Amount of total HTTP requests',
+    labelNames: ['status', 'endpoint', 'method'],
+    registers: [endpointsRegistry]
+});
+
+exports.addEndpointMetrics = async (req, res, next) => {
+    const callbackOnFinished = () => {
+        const labelsObject = {
+            status: res.statusCode,
+            endpoint: req.originalUrl,
+            method: req.method
+        };
+
+        responseCounter.inc(labelsObject);
+    };
+
+    req.startTime = Date.now();
+
+    onFinished(res, callbackOnFinished);
+    return next();
+};
+
+exports.getEndpointMetrics = async (req, res) => {
+    res.set('Content-Type', endpointsRegistry.contentType);
+    res.end(endpointsRegistry.metrics());
+};
diff --git a/lib/server.js b/lib/server.js
index c7d406cb..aa4b44d4 100644
--- a/lib/server.js
+++ b/lib/server.js
@@ -10,6 +10,7 @@ const middlewares = require('./middlewares');
 const integrations = require('./integrations');
 const categories = require('./categories');
 const metrics = require('./metrics');
+const endpointsMetrics = require('./endpoints_metrics');
 const db = require('./sequelize');
 
 const server = express();
@@ -29,6 +30,7 @@ process.on('unhandledRejection', (err) => {
 
 GeneralRouter.get('/healthcheck', middlewares.healthcheck);
 GeneralRouter.get('/metrics', metrics.getMetrics);
+GeneralRouter.get('/metrics/requests', endpointsMetrics.getEndpointMetrics);
 GeneralRouter.use(middlewares.authenticateUser);
 
 // integrations and codes
@@ -49,6 +51,7 @@ GeneralRouter.get('/categories/:category_id', categories.findCategory, categorie
 GeneralRouter.put('/categories/:category_id', categories.findCategory, categories.updateCategory);
 GeneralRouter.delete('/categories/:category_id', categories.findCategory, categories.deleteCategory);
 
+server.use(endpointsMetrics.addEndpointMetrics);
 server.use('/', GeneralRouter);
 server.use(middlewares.notFound);
 server.use(middlewares.errorHandler);
diff --git a/package.json b/package.json
index 7de332ca..1d821616 100644
--- a/package.json
+++ b/package.json
@@ -67,6 +67,7 @@
     "joi": "^14.3.1",
     "moment": "^2.24.0",
     "morgan": "^1.9.1",
+    "on-finished": "^2.3.0",
     "pg": "^7.12.1",
     "prom-client": "^11.5.3",
     "request": "^2.88.0",
diff --git a/test/api/metrics.test.js b/test/api/metrics.test.js
index e071d07b..03ee249d 100644
--- a/test/api/metrics.test.js
+++ b/test/api/metrics.test.js
@@ -14,7 +14,7 @@ describe('Metrics requests', () => {
         mock.cleanAll();
     });
 
-    test('should return data correctly', async () => {
+    test('should return data correctly on /metrics', async () => {
         await generator.createCategory({});
 
         const integration = await generator.createIntegration({});
@@ -29,4 +29,15 @@ describe('Metrics requests', () => {
 
         expect(res.statusCode).toEqual(200);
     });
+
+
+    test('should return data correctly on /metrics/requests', async () => {
+        const res = await request({
+            uri: '/metrics/requests',
+            method: 'GET',
+            json: false
+        });
+
+        expect(res.statusCode).toEqual(200);
+    });
 });