Gazebo_simulation-Frontend/node_modules/node-fetch/index.js

272 lines
7.9 KiB
JavaScript

/**
* index.js
*
* a request API compatible with window.fetch
*/
var parse_url = require('url').parse;
var resolve_url = require('url').resolve;
var http = require('http');
var https = require('https');
var zlib = require('zlib');
var stream = require('stream');
var Body = require('./lib/body');
var Response = require('./lib/response');
var Headers = require('./lib/headers');
var Request = require('./lib/request');
var FetchError = require('./lib/fetch-error');
// commonjs
module.exports = Fetch;
// es6 default export compatibility
module.exports.default = module.exports;
/**
* Fetch class
*
* @param Mixed url Absolute url or Request instance
* @param Object opts Fetch options
* @return Promise
*/
function Fetch(url, opts) {
// allow call as function
if (!(this instanceof Fetch))
return new Fetch(url, opts);
// allow custom promise
if (!Fetch.Promise) {
throw new Error('native promise missing, set Fetch.Promise to your favorite alternative');
}
Body.Promise = Fetch.Promise;
var self = this;
// wrap http.request into fetch
return new Fetch.Promise(function(resolve, reject) {
// build request object
var options = new Request(url, opts);
if (!options.protocol || !options.hostname) {
throw new Error('only absolute urls are supported');
}
if (options.protocol !== 'http:' && options.protocol !== 'https:') {
throw new Error('only http(s) protocols are supported');
}
var send;
if (options.protocol === 'https:') {
send = https.request;
} else {
send = http.request;
}
// normalize headers
var headers = new Headers(options.headers);
if (options.compress) {
headers.set('accept-encoding', 'gzip,deflate');
}
if (!headers.has('user-agent')) {
headers.set('user-agent', 'node-fetch/1.0 (+https://github.com/bitinn/node-fetch)');
}
if (!headers.has('connection') && !options.agent) {
headers.set('connection', 'close');
}
if (!headers.has('accept')) {
headers.set('accept', '*/*');
}
// detect form data input from form-data module, this hack avoid the need to pass multipart header manually
if (!headers.has('content-type') && options.body && typeof options.body.getBoundary === 'function') {
headers.set('content-type', 'multipart/form-data; boundary=' + options.body.getBoundary());
}
// bring node-fetch closer to browser behavior by setting content-length automatically
if (!headers.has('content-length') && /post|put|patch|delete/i.test(options.method)) {
if (typeof options.body === 'string') {
headers.set('content-length', Buffer.byteLength(options.body));
// detect form data input from form-data module, this hack avoid the need to add content-length header manually
} else if (options.body && typeof options.body.getLengthSync === 'function') {
// for form-data 1.x
if (options.body._lengthRetrievers && options.body._lengthRetrievers.length == 0) {
headers.set('content-length', options.body.getLengthSync().toString());
// for form-data 2.x
} else if (options.body.hasKnownLength && options.body.hasKnownLength()) {
headers.set('content-length', options.body.getLengthSync().toString());
}
// this is only necessary for older nodejs releases (before iojs merge)
} else if (options.body === undefined || options.body === null) {
headers.set('content-length', '0');
}
}
options.headers = headers.raw();
// http.request only support string as host header, this hack make custom host header possible
if (options.headers.host) {
options.headers.host = options.headers.host[0];
}
// send request
var req = send(options);
var reqTimeout;
if (options.timeout) {
req.once('socket', function(socket) {
reqTimeout = setTimeout(function() {
req.abort();
reject(new FetchError('network timeout at: ' + options.url, 'request-timeout'));
}, options.timeout);
});
}
req.on('error', function(err) {
clearTimeout(reqTimeout);
reject(new FetchError('request to ' + options.url + ' failed, reason: ' + err.message, 'system', err));
});
req.on('response', function(res) {
clearTimeout(reqTimeout);
// handle redirect
if (self.isRedirect(res.statusCode) && options.redirect !== 'manual') {
if (options.redirect === 'error') {
reject(new FetchError('redirect mode is set to error: ' + options.url, 'no-redirect'));
return;
}
if (options.counter >= options.follow) {
reject(new FetchError('maximum redirect reached at: ' + options.url, 'max-redirect'));
return;
}
if (!res.headers.location) {
reject(new FetchError('redirect location header missing at: ' + options.url, 'invalid-redirect'));
return;
}
// per fetch spec, for POST request with 301/302 response, or any request with 303 response, use GET when following redirect
if (res.statusCode === 303
|| ((res.statusCode === 301 || res.statusCode === 302) && options.method === 'POST'))
{
options.method = 'GET';
delete options.body;
delete options.headers['content-length'];
}
options.counter++;
resolve(Fetch(resolve_url(options.url, res.headers.location), options));
return;
}
// normalize location header for manual redirect mode
var headers = new Headers(res.headers);
if (options.redirect === 'manual' && headers.has('location')) {
headers.set('location', resolve_url(options.url, headers.get('location')));
}
// prepare response
var body = res.pipe(new stream.PassThrough());
var response_options = {
url: options.url
, status: res.statusCode
, statusText: res.statusMessage
, headers: headers
, size: options.size
, timeout: options.timeout
};
// response object
var output;
// in following scenarios we ignore compression support
// 1. compression support is disabled
// 2. HEAD request
// 3. no content-encoding header
// 4. no content response (204)
// 5. content not modified response (304)
if (!options.compress || options.method === 'HEAD' || !headers.has('content-encoding') || res.statusCode === 204 || res.statusCode === 304) {
output = new Response(body, response_options);
resolve(output);
return;
}
// otherwise, check for gzip or deflate
var name = headers.get('content-encoding');
// for gzip
if (name == 'gzip' || name == 'x-gzip') {
body = body.pipe(zlib.createGunzip());
output = new Response(body, response_options);
resolve(output);
return;
// for deflate
} else if (name == 'deflate' || name == 'x-deflate') {
// handle the infamous raw deflate response from old servers
// a hack for old IIS and Apache servers
var raw = res.pipe(new stream.PassThrough());
raw.once('data', function(chunk) {
// see http://stackoverflow.com/questions/37519828
if ((chunk[0] & 0x0F) === 0x08) {
body = body.pipe(zlib.createInflate());
} else {
body = body.pipe(zlib.createInflateRaw());
}
output = new Response(body, response_options);
resolve(output);
});
return;
}
// otherwise, use response as-is
output = new Response(body, response_options);
resolve(output);
return;
});
// accept string, buffer or readable stream as body
// per spec we will call tostring on non-stream objects
if (typeof options.body === 'string') {
req.write(options.body);
req.end();
} else if (options.body instanceof Buffer) {
req.write(options.body);
req.end();
} else if (typeof options.body === 'object' && options.body.pipe) {
options.body.pipe(req);
} else if (typeof options.body === 'object') {
req.write(options.body.toString());
req.end();
} else {
req.end();
}
});
};
/**
* Redirect code matching
*
* @param Number code Status code
* @return Boolean
*/
Fetch.prototype.isRedirect = function(code) {
return code === 301 || code === 302 || code === 303 || code === 307 || code === 308;
}
// expose Promise
Fetch.Promise = global.Promise;
Fetch.Response = Response;
Fetch.Headers = Headers;
Fetch.Request = Request;