src/app/lib/request.js
// Browser Request
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
var XHR = XMLHttpRequest
if (!XHR) throw new Error('missing XMLHttpRequest')
request.log = {
'trace': noop, 'debug': noop, 'info': noop, 'warn': noop, 'error': noop
}
var DEFAULT_TIMEOUT = 3 * 60 * 1000 // 3 minutes
//
// request
//
function request(options, callback) {
// The entry-point to the API: prep the options object and pass the real work to run_xhr.
if(typeof callback !== 'function')
throw new Error('Bad callback given: ' + callback)
if(!options)
throw new Error('No options given')
var options_onResponse = options.onResponse; // Save this for later.
if(typeof options === 'string')
options = {'uri':options};
else
options = JSON.parse(JSON.stringify(options)); // Use a duplicate for mutating.
options.onResponse = options_onResponse // And put it back.
if (options.verbose) request.log = getLogger();
if(options.url) {
options.uri = options.url;
delete options.url;
}
if(!options.uri && options.uri !== "")
throw new Error("options.uri is a required argument");
if(typeof options.uri != "string")
throw new Error("options.uri must be a string");
var unsupported_options = ['proxy', '_redirectsFollowed', 'maxRedirects', 'followRedirect']
for (var i = 0; i < unsupported_options.length; i++)
if(options[ unsupported_options[i] ])
throw new Error("options." + unsupported_options[i] + " is not supported")
options.callback = callback
options.method = options.method || 'GET';
options.headers = options.headers || {};
options.body = options.body || null
options.timeout = options.timeout || request.DEFAULT_TIMEOUT
if(options.headers.host)
throw new Error("Options.headers.host is not supported");
if(options.json) {
options.headers.accept = options.headers.accept || 'application/json'
if(options.method !== 'GET')
options.headers['content-type'] = 'application/json'
if(typeof options.json !== 'boolean')
options.body = JSON.stringify(options.json)
else if(typeof options.body !== 'string')
options.body = JSON.stringify(options.body)
}
//BEGIN QS Hack
var serialize = function(obj) {
var str = [];
for(var p in obj)
if (obj.hasOwnProperty(p)) {
str.push(encodeURIComponent(p) + "=" + encodeURIComponent(obj[p]));
}
return str.join("&");
}
if(options.qs){
var qs = (typeof options.qs == 'string')? options.qs : serialize(options.qs);
if(options.uri.indexOf('?') !== -1){ //no get params
options.uri = options.uri+'&'+qs;
}else{ //existing get params
options.uri = options.uri+'?'+qs;
}
}
//END QS Hack
//BEGIN FORM Hack
var multipart = function(obj) {
//todo: support file type (useful?)
var result = {};
result.boundry = '-------------------------------'+Math.floor(Math.random()*1000000000);
var lines = [];
for(var p in obj){
if (obj.hasOwnProperty(p)) {
lines.push(
'--'+result.boundry+"\n"+
'Content-Disposition: form-data; name="'+p+'"'+"\n"+
"\n"+
obj[p]+"\n"
);
}
}
lines.push( '--'+result.boundry+'--' );
result.body = lines.join('');
result.length = result.body.length;
result.type = 'multipart/form-data; boundary='+result.boundry;
return result;
}
if(options.form){
if(typeof options.form == 'string') throw('form name unsupported');
if(options.method === 'POST'){
var encoding = (options.encoding || 'application/x-www-form-urlencoded').toLowerCase();
options.headers['content-type'] = encoding;
switch(encoding){
case 'application/x-www-form-urlencoded':
options.body = serialize(options.form).replace(/%20/g, "+");
break;
case 'multipart/form-data':
var multi = multipart(options.form);
//options.headers['content-length'] = multi.length;
options.body = multi.body;
options.headers['content-type'] = multi.type;
break;
default : throw new Error('unsupported encoding:'+encoding);
}
}
}
//END FORM Hack
// If onResponse is boolean true, call back immediately when the response is known,
// not when the full request is complete.
options.onResponse = options.onResponse || noop
if(options.onResponse === true) {
options.onResponse = callback
options.callback = noop
}
// XXX Browsers do not like this.
//if(options.body)
// options.headers['content-length'] = options.body.length;
// HTTP basic authentication
if(!options.headers.authorization && options.auth) {
auth = options.auth.username + ':' + options.auth.password
auth = btoa(unescape(encodeURIComponent(auth)));
options.headers.authorization = 'Basic ' + auth;
}
return run_xhr(options)
}
var req_seq = 0
function run_xhr(options) {
var xhr = new XHR
, timed_out = false
, is_cors = is_crossDomain(options.uri)
, supports_cors = ('withCredentials' in xhr)
req_seq += 1
xhr.seq_id = req_seq
xhr.id = req_seq + ': ' + options.method + ' ' + options.uri
xhr._id = xhr.id // I know I will type "_id" from habit all the time.
if(is_cors && !supports_cors) {
var cors_err = new Error('Browser does not support cross-origin request: ' + options.uri)
cors_err.cors = 'unsupported'
return options.callback(cors_err, xhr)
}
xhr.timeoutTimer = setTimeout(too_late, options.timeout)
function too_late() {
timed_out = true
var er = new Error('ETIMEDOUT')
er.code = 'ETIMEDOUT'
er.duration = options.timeout
request.log.error('Timeout', { 'id':xhr._id, 'milliseconds':options.timeout })
return options.callback(er, xhr)
}
// Some states can be skipped over, so remember what is still incomplete.
var did = {'response':false, 'loading':false, 'end':false}
xhr.onreadystatechange = on_state_change
xhr.open(options.method, options.uri, true) // asynchronous
if(is_cors)
xhr.withCredentials = !! options.withCredentials
xhr.send(options.body)
return xhr
function on_state_change(event) {
if(timed_out)
return request.log.debug('Ignoring timed out state change', {'state':xhr.readyState, 'id':xhr.id})
request.log.debug('State change', {'state':xhr.readyState, 'id':xhr.id, 'timed_out':timed_out})
if(xhr.readyState === XHR.OPENED) {
request.log.debug('Request started', {'id':xhr.id})
for (var key in options.headers)
xhr.setRequestHeader(key, options.headers[key])
}
else if(xhr.readyState === XHR.HEADERS_RECEIVED)
on_response()
else if(xhr.readyState === XHR.LOADING) {
on_response()
on_loading()
}
else if(xhr.readyState === XHR.DONE) {
on_response()
on_loading()
on_end()
}
}
function on_response() {
if(did.response)
return
did.response = true
request.log.debug('Got response', {'id':xhr.id, 'status':xhr.status})
clearTimeout(xhr.timeoutTimer)
xhr.statusCode = xhr.status // Node request compatibility
// Detect failed CORS requests.
if(is_cors && xhr.statusCode == 0) {
var cors_err = new Error('CORS request rejected: ' + options.uri)
cors_err.cors = 'rejected'
// Do not process this request further.
did.loading = true
did.end = true
return options.callback(cors_err, xhr)
}
options.onResponse(null, xhr)
}
function on_loading() {
if(did.loading)
return
did.loading = true
request.log.debug('Response body loading', {'id':xhr.id})
// TODO: Maybe simulate "data" events by watching xhr.responseText
}
function on_end() {
if(did.end)
return
did.end = true
request.log.debug('Request done', {'id':xhr.id})
xhr.body = xhr.responseText
if(options.json) {
try { xhr.body = JSON.parse(xhr.responseText) }
catch (er) { return options.callback(er, xhr) }
}
options.callback(null, xhr, xhr.body)
}
} // request
request.withCredentials = false;
request.DEFAULT_TIMEOUT = DEFAULT_TIMEOUT;
//
// defaults
//
request.defaults = function(options, requester) {
var def = function (method) {
var d = function (params, callback) {
if(typeof params === 'string')
params = {'uri': params};
else {
params = JSON.parse(JSON.stringify(params));
}
for (var i in options) {
if (params[i] === undefined) params[i] = options[i]
}
return method(params, callback)
}
return d
}
var de = def(request)
de.get = def(request.get)
de.post = def(request.post)
de.put = def(request.put)
de.head = def(request.head)
return de
}
//
// HTTP method shortcuts
//
var shortcuts = [ 'get', 'put', 'post', 'head' ];
shortcuts.forEach(function(shortcut) {
var method = shortcut.toUpperCase();
var func = shortcut.toLowerCase();
request[func] = function(opts) {
if(typeof opts === 'string')
opts = {'method':method, 'uri':opts};
else {
opts = JSON.parse(JSON.stringify(opts));
opts.method = method;
}
var args = [opts].concat(Array.prototype.slice.apply(arguments, [1]));
return request.apply(this, args);
}
})
//
// CouchDB shortcut
//
request.couch = function(options, callback) {
if(typeof options === 'string')
options = {'uri':options}
// Just use the request API to do JSON.
options.json = true
if(options.body)
options.json = options.body
delete options.body
callback = callback || noop
var xhr = request(options, couch_handler)
return xhr
function couch_handler(er, resp, body) {
if(er)
return callback(er, resp, body)
if((resp.statusCode < 200 || resp.statusCode > 299) && body.error) {
// The body is a Couch JSON object indicating the error.
er = new Error('CouchDB error: ' + (body.error.reason || body.error.error || body.error))
for (var key in body)
er[key] = body[key]
return callback(er, resp, body);
}
return callback(er, resp, body);
}
}
//
// Utility
//
function noop() {}
function getLogger() {
var logger = {}
, levels = ['trace', 'debug', 'info', 'warn', 'error']
, level, i
for(i = 0; i < levels.length; i++) {
level = levels[i]
logger[level] = noop
if(typeof console !== 'undefined' && console && console[level])
logger[level] = formatted(console, level)
}
return logger
}
function formatted(obj, method) {
return formatted_logger
function formatted_logger(str, context) {
if(typeof context === 'object')
str += ' ' + JSON.stringify(context)
return obj[method].call(obj, str)
}
}
// Return whether a URL is a cross-domain request.
function is_crossDomain(url) {
var rurl = /^([\w\+\.\-]+:)(?:\/\/([^\/?#:]*)(?::(\d+))?)?/
// jQuery #8138, IE may throw an exception when accessing
// a field from window.location if document.domain has been set
var ajaxLocation
try { ajaxLocation = location.href }
catch (e) {
// Use the href attribute of an A element since IE will modify it given document.location
ajaxLocation = document.createElement( "a" );
ajaxLocation.href = "";
ajaxLocation = ajaxLocation.href;
}
var ajaxLocParts = rurl.exec(ajaxLocation.toLowerCase()) || []
, parts = rurl.exec(url.toLowerCase() )
var result = !!(
parts &&
( parts[1] != ajaxLocParts[1]
|| parts[2] != ajaxLocParts[2]
|| (parts[3] || (parts[1] === "http:" ? 80 : 443)) != (ajaxLocParts[3] || (ajaxLocParts[1] === "http:" ? 80 : 443))
)
)
//console.debug('is_crossDomain('+url+') -> ' + result)
return result
}
module.exports = request;