How can I inject a custom HTTP Header into every request that SuperAgent makes?

Question

Clearly SuperAgent supports custom HTTP headers:

request
   .post(\'/api/pet\')
   .send({ name: \'Manny\', species: \'cat\' })
   .set(\'X-API-Key\', \'foobar\'         


        

Answer 1

I'd just make a separate module with something like this:

myagent.js

var superagent = require('superagent');

var defaultHeaders = {};
function isObject(obj) { return Object(obj) === obj; };

function request(method, url) {
   return superagent(method, url).set(defaultHeaders);
}

request.set = function (field, value) {
   if (isObject(field)) {
      for(var key in field) this.set(key, field[key]);
      return this;
   }
   defaultHeaders[field] = value;
   return this;
}
module.exports = request;

Usage

var request = require('./myagent');
request.set({'X-My-Header': 'foo'}); // sets the default

request.get('/bar').send() // will send the default header

The module behaves the same way as superagent but sets default headers before returning the Request object. See here