JavaScript has similar client libraries to Python. In fact, it is even easier to instrument Node.js express applications with the use of express-prom-bundle, which in turn uses prom-client. You can install this library for your use with this command:
npm install express-prom-bundle --save
You can then use it in your code. The following will set up a middleware for express:
const promBundle = require("express-prom-bundle");const metricsMiddleware = promBundle({includeMethod: true});
And then, you simply include the middleware, as you're setting up this application:
app.use(metricsMiddleware)
The example code at https://github.com/kubernetes-for-developers/kfd-nodejs has these updates, and you can check out this ...