bump 6.3.0

README.md

@@ -52,7 +52,7 @@ Which labels to include in `http_request_duration_seconds` metric:
 * **includeUp**: include an auxiliary "up"-metric which always returns 1, default: **true**
 * **metricsPath**: replace the `/metrics` route with a **regex** or exact **string**. Note: it is highly recommended to just stick to the default
 * **metricType**: histogram/summary selection. See more details below
-
+* **bypass**: function taking express request as an argument and determines whether the given request should be excluded in the metrics, default: **() => false**
 
 ### metricType option ###
 

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "express-prom-bundle",
-  "version": "6.2.0",
+  "version": "6.3.0",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {

package.json

@@ -1,6 +1,6 @@
 {
   "name": "express-prom-bundle",
-  "version": "6.2.0",
+  "version": "6.3.0",
   "description": "express middleware with popular prometheus metrics in one bundle",
   "main": "src/index.js",
   "keywords": [

spec/index.spec.js

@@ -200,6 +200,46 @@ describe('index', () => {
       });
   });
 
+  it('bypass requests', done => {
+    const app = express();
+    const instance = bundle({
+      bypass: (req)=> {
+        // metrics added here to attempt skipping /metrics
+        // this should fail though, because serving /metrics preceeds bypassing
+        return !!req.url.match(/test|bad.word|metrics/)
+      }
+    });
+    app.use(instance);
+    app.use('/test', (req, res) => res.send('it worked'));
+    app.use('/some/bad-word', (req, res) => res.send('it worked too'));
+    app.use('/good-word', (req, res) => res.send('this will be counted'));
+    const agent = supertest(app);
+    agent
+      .get('/test')
+      .end(() => {
+        agent
+          .get('/some/bad-word')
+          .end(() => {
+            agent
+              .get('/good-word')
+              .end(() => {
+                const metricHashMap = instance.metrics.http_request_duration_seconds.hashMap;
+                expect(metricHashMap['status_code:200']).toBeDefined();
+
+                // only /good-word should be counted
+                expect(metricHashMap['status_code:200'].count).toBe(1);
+
+                agent
+                  .get('/metrics')
+                  .end((err, res) => {
+                    expect(res.status).toBe(200);
+                    done();
+                  });
+              });
+          });
+      });
+  });
+
   it('complains about deprecated options', () => {
     expect(() => bundle({prefix: 'hello'})).toThrow();
   });

src/index.js

@@ -137,6 +137,12 @@ function main(opts) {
         return metricsMiddleware(req, res);
     }
 
+    // bypass() is checked only after /metrics was processed
+    // if you wish to disable /metrics use autoregister:false instead
+    if (opts.bypass && opts.bypass(req)) {
+      return next();
+    }
+
     if (opts.excludeRoutes && matchVsRegExps(path, opts.excludeRoutes)) {
       return next();
     }

types/index.d.ts

@@ -28,6 +28,8 @@ declare namespace express_prom_bundle {
     includePath?: boolean;
     includeUp?: boolean;
 
+    bypass?: (req: Request) => boolean;
+
     metricType?: 'summary' | 'histogram';
     metricsPath?: string;
     httpDurationMetricName?: string;