[RFC] API for canceling HTTP requests

Overview

I would like to revive the discussion about canceling HTTP requests (#50) as there is clearly a demand for this feature. I suggest considering the following options. /cc @mzabriskie

Option 1

API

var axios = require('axios');

function generateRequestId() {
  // Return a unique request ID
}

var requestId = generateRequestId(); 
axios.get('/user', { requestId: requestId });
axios.abort(requestId);

Implementation

PR #330

Option 2

API

var axios = require('axios');
var Cancellation = axios.Cancellation;

var cancellation = new Cancellation();
axios.get('/user', { cancellation: cancellation });
cancellation.cancel();

Notes

• When a request is canceled, the Promise is rejected with a CancellationError. This allows the caller to distinguish between a cancellation and a failure.
• The same Cancellation object can be used to cancel multiple different requests.

Implementation

I created a separate library that can be used as a base for implementing request cancellation in axios: https://github.com/nickuraltsev/cancel. (The example on the README.md shows how to implement a simple HTTP client that supports cancellation.) We can copy all the code from this library to axios or add this library as a dependency.

[nickuraltsev]

Great, I’ll submit a PR soon.

[nickuraltsev]

I’ve just submitted a PR