Add useOrginalUrl flag

README.md

@@ -31,6 +31,7 @@ npm i --save express-prometheus-middleware
 | extraMasks | Optional, list of regexes to be used as argument to [url-value-parser](https://www.npmjs.com/package/url-value-parser), this will cause extra route params,  to be replaced with a `#val` placeholder.  | no extra masks: `[]` |
 | authenticate | Optional authentication callback, the function should receive as argument, the `req` object and return truthy for sucessfull authentication, or falsy, otherwise. This option supports Promise results. | `null` |
 | prefix | Optional prefix for the metrics name | no prefix added | |
+| useOriginalUrl | Optional flag, in `false` will change you route label from url to the router mask | `true` | |
 
 ### Example
 
@@ -57,6 +58,10 @@ app.use(promMid({
    * reformat URL path names and replace the values found with a placeholder value
   */
   // extraMasks: [/..:..:..:..:..:../],
+  /**
+    * Uncommenting the `useOriginalUrl` config and setting it to `false` will swap using you route label from '/data/1' to '/data/:id'
+  /*
+  // useOriginalUrl: true,
 }));
 
 // curl -X GET localhost:9091/hello?name=Chuck%20Norris

src/index.js

@@ -21,6 +21,8 @@ const defaultOptions = {
   // these are aribtrary values since i dont know any better ¯\_(ツ)_/¯
   requestDurationBuckets: Prometheus.exponentialBuckets(0.05, 1.75, 8),
   extraMasks: [],
+  // this is the flag which swap using originalUrl and route.path params
+  useOriginalUrl: true,
 };
 
 module.exports = (userOptions = {}) => {
@@ -40,11 +42,15 @@ module.exports = (userOptions = {}) => {
    * of the RED metrics.
    */
   const redMiddleware = ResponseTime((req, res, time) => {
-    const { originalUrl, method } = req;
+    const { originalUrl, route: routeData, method } = req;
     // will replace ids from the route with `#val` placeholder this serves to
     // measure the same routes, e.g., /image/id1, and /image/id2, will be
     // treated as the same route
-    const route = normalizePath(originalUrl, options.extraMasks);
+    if (!options.useOriginalUrl && !routeData) {
+      return;
+    }
+
+    const route = normalizePath(options.useOriginalUrl ? originalUrl : routeData.path, options.extraMasks);
 
     if (route !== metricsPath) {
       const status = normalizeStatusCode(res.statusCode);