ankur-anand

Part 1: Why bubbling is good

We start with the following code

function startListening(server, cb) {
  server.listen(99999, 'localhost', cb)
}

ankur-anand

Post Mortem Debugging in NodeJS in the Light of Promises

Context:

we're discussing how we can safely abort on unhandled rejections and obtain meaningful debugging information. Related reading: https://gist.github.com/misterdjules/2969aa1b5e6440a7e401#file-post-mortem-debugging-with-promises-md.

In particular, we're discussing https://gist.github.com/misterdjules/2969aa1b5e6440a7e401#removing-implicit-trycatch-blocks-from-v8s-promises-implementation

Othe recommended reading: On unhandledRejection https://gist.github.com/benjamingr/0237932cee84712951a2

ankur-anand

Possibly Unhandled Rejection NodeJS Promise Hook

###Unhandled Rejection Tracking

Several promise libraries such as bluebird and when as well as some native promise implementations offer potentially unhandled rejection tracking. This means that the following:

Promise.reject(new Error("err")); // never attach a `catch`

ankur-anand

Promise Error Handling Hooks

Problem

A common desire in web programming is to log any uncaught exceptions back to the server. The typical method for doing this is

window.onerror = (message, url, line, column, error) => {
  // log `error` back to the server
};

ankur-anand

listen(port, cb) {
      const server = http.createServer((req, res) => {
        res.statusCode = 200;
        res.setHeader("Content-Type", "text/plain");
        res.end("Hello World\n");
      });

      return server.listen.apply(server, arguments);
}

ankur-anand

const router = [{
    path: '*',
    method: '*',
    handle: function(req, res) {
        res.writeHead(200, {'Content-Type': 'text/plain'});
        res.end('404');
    }
}];

ankur-anand

The Ultimate Unit Testing Cheat-sheet

For Mocha, Chai and Sinon

using mocha/chai/sinon for node.js unit-tests? check out my utility: mocha-stirrer to easily reuse test components and mock require dependencies

---

• Sinon Chai
• Chai
• Sinon
• Mocha

ankur-anand

var os = require("os");

//Create function to get CPU information
function cpuAverage() {

  //Initialise sum of idle and time of cores and fetch CPU info
  var totalIdle = 0, totalTick = 0;
  var cpus = os.cpus();

  //Loop through CPU cores

ankur-anand

Common Options

-#, --progress-bar Make curl display a simple progress bar instead of the more informational standard meter.

-b, --cookie <name=data> Supply cookie with request. If no =, then specifies the cookie file to use (see -c).

-c, --cookie-jar <file name> File to save response cookies to.

ankur-anand

Per https://code.google.com/p/v8/codesearch#v8/trunk/src/runtime.cc


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