traverson/browser/lib/shim/request.js

Hypermedia API/HATEOAS client for Node.js and the browser

'use strict';

var superagent = require('superagent');

function Request() {}

Request.prototype.get = function(uri, options, callback) {
  return mapRequest(superagent.get(uri), options)
    .end(handleResponse(callback));
};

Request.prototype.post = function(uri, options, callback) {
  return mapRequest(superagent.post(uri), options)
    .end(handleResponse(callback));
};

Request.prototype.put = function(uri, options, callback) {
  return mapRequest(superagent.put(uri), options)
    .end(handleResponse(callback));
};

Request.prototype.patch = function(uri, options, callback) {
  return mapRequest(superagent.patch(uri), options)
    .end(handleResponse(callback));
};

Request.prototype.del = function(uri, options, callback) {
  return mapRequest(superagent.del(uri), options)
    .end(handleResponse(callback));
};

function mapRequest(superagentRequest, options) {
  options = options || {};
  mapQuery(superagentRequest, options);
  mapHeaders(superagentRequest, options);
  mapAuth(superagentRequest, options);
  mapBody(superagentRequest, options);
  mapForm(superagentRequest, options);
  mapWithCredentials(superagentRequest, options);
  return superagentRequest;
}

function mapQuery(superagentRequest, options) {
  var qs = options.qs;
  if (qs != null) {
    superagentRequest = superagentRequest.query(qs);
  }
}

function mapHeaders(superagentRequest, options) {
  var headers = options.headers;
  if (headers != null) {
    superagentRequest = superagentRequest.set(headers);
  }
}

function mapAuth(superagentRequest, options) {
  var auth = options.auth;
  if (auth != null) {
    superagentRequest = superagentRequest.auth(
      auth.user || auth.username,
      auth.pass || auth.password
    );
  }
}

function mapBody(superagentRequest, options) {
  if (options != null) {
    var body = options.body;
    if (body != null) {
      superagentRequest = superagentRequest.send(body);
    }
  }
}

function mapForm(superagentRequest, options) {
  if (options != null) {
    var form = options.form;
    if (form != null) {
      // content-type header needs to be set before calling send AND it NEEDS
      // to be all lower case otherwise superagent automatically sets
      // application/json as content-type :-/
      superagentRequest = superagentRequest.set('content-type',
          'application/x-www-form-urlencoded');
      superagentRequest = superagentRequest.send(form);
    }
  }
}

function mapWithCredentials(superagentRequest, options) {
  if (options != null) {
    var withCredentials = options.withCredentials;
    if (withCredentials === true) {
      // https://visionmedia.github.io/superagent/#cors
      superagentRequest.withCredentials();
    }
  }
}

// map XHR response object properties to Node.js request lib's response object
// properties
function mapResponse(response) {
  response.body = response.text;
  response.statusCode = response.status;
  return response;
}

function handleResponse(callback) {
  return function(err, response) {
    if (err) {
      if (!response) {
        // network error or timeout, no response
        return callback(err);
      } else {
        // Since 1.0.0 superagent calls the callback with an error if the status
        // code of the response is not in the 2xx range. In this cases, it also
        // passes in the response. To align things with request, call the
        // callback without the error but just with the response.
        callback(null, mapResponse(response));
      }
    } else {
      callback(null, mapResponse(response));
    }
  };
}

module.exports = new Request();