var url = require("url");
var URL = url.URL;
var http = require("http");
var https = require("https");
var Writable = require("stream").Writable;
var assert = require("assert");
var debug = require("./debug");
// Create handlers that pass events from native requests
var events = ["abort", "aborted", "connect", "error", "socket", "timeout"];
var eventHandlers = Object.create(null);
events.forEach(function (event) {
eventHandlers[event] = function (arg1, arg2, arg3) {
this._redirectable.emit(event, arg1, arg2, arg3);
};
});
var InvalidUrlError = createErrorType(
"ERR_INVALID_URL",
"Invalid URL",
TypeError
);
// Error types with codes
var RedirectionError = createErrorType(
"ERR_FR_REDIRECTION_FAILURE",
"Redirected request failed"
);
var TooManyRedirectsError = createErrorType(
"ERR_FR_TOO_MANY_REDIRECTS",
"Maximum number of redirects exceeded"
);
var MaxBodyLengthExceededError = createErrorType(
"ERR_FR_MAX_BODY_LENGTH_EXCEEDED",
"Request body larger than maxBodyLength limit"
);
var WriteAfterEndError = createErrorType(
"ERR_STREAM_WRITE_AFTER_END",
"write after end"
);
// istanbul ignore next
var destroy = Writable.prototype.destroy || noop;
// An HTTP(S) request that can be redirected
function RedirectableRequest(options, responseCallback) {
// Initialize the request
Writable.call(this);
this._sanitizeOptions(options);
this._options = options;
this._ended = false;
this._ending = false;
this._redirectCount = 0;
this._redirects = [];
this._requestBodyLength = 0;
this._requestBodyBuffers = [];
// Attach a callback if passed
if (responseCallback) {
this.on("response", responseCallback);
}
// React to responses of native requests
var self = this;
this._onNativeResponse = function (response) {
self._processResponse(response);
};
// Perform the first request
this._performRequest();
}
RedirectableRequest.prototype = Object.create(Writable.prototype);
RedirectableRequest.prototype.abort = function () {
destroyRequest(this._currentRequest);
this._currentRequest.abort();
this.emit("abort");
};
RedirectableRequest.prototype.destroy = function (error) {
destroyRequest(this._currentRequest, error);
destroy.call(this, error);
return this;
};
// Writes buffered data to the current native request
RedirectableRequest.prototype.write = function (data, encoding, callback) {
// Writing is not allowed if end has been called
if (this._ending) {
throw new WriteAfterEndError();
}
// Validate input and shift parameters if necessary
if (!isString(data) && !isBuffer(data)) {
throw new TypeError("data should be a string, Buffer or Uint8Array");
}
if (isFunction(encoding)) {
callback = encoding;
encoding = null;
}
// Ignore empty buffers, since writing them doesn't invoke the callback
// https://github.com/nodejs/node/issues/22066
if (data.length === 0) {
if (callback) {
callback();
}
return;
}
// Only write when we don't exceed the maximum body length
if (this._requestBodyLength + data.length <= this._options.maxBodyLength) {
this._requestBodyLength += data.length;
this._requestBodyBuffers.push({ data: data, encoding: encoding });
this._currentRequest.write(data, encoding, callback);
}
// Error when we exceed the maximum body length
else {
this.emit("error", new MaxBodyLengthExceededError());
this.abort();
}
};
// Ends the current native request
RedirectableRequest.prototype.end = function (data, encoding, callback) {
// Shift parameters if necessary
if (isFunction(data)) {
callback = data;
data = encoding = null;
}
else if (isFunction(encoding)) {
callback = encoding;
encoding = null;
}
// Write data if needed and end
if (!data) {
this._ended = this._ending = true;
this._currentRequest.end(null, null, callback);
}
else {
var self = this;
var currentRequest = this._currentRequest;
this.write(data, encoding, function () {
self._ended = true;
currentRequest.end(null, null, callback);
});
this._ending = true;
}
};
// Sets a header value on the current native request
RedirectableRequest.prototype.setHeader = function (name, value) {
this._options.headers[name] = value;
this._currentRequest.setHeader(name, value);
};
// Clears a header value on the current native request
RedirectableRequest.prototype.removeHeader = function (name) {
delete this._options.headers[name];
this._currentRequest.removeHeader(name);
};
// Global timeout for all underlying requests
RedirectableRequest.prototype.setTimeout = function (msecs, callback) {
var self = this;
// Destroys the socket on timeout
function destroyOnTimeout(socket) {
socket.setTimeout(msecs);
socket.removeListener("timeout", socket.destroy);
socket.addListener("timeout", socket.destroy);
}
// Sets up a timer to trigger a timeout event
function startTimer(socket) {
if (self._timeout) {
clearTimeout(self._timeout);
}
self._timeout = setTimeout(function () {
self.emit("timeout");
clearTimer();
}, msecs);
destroyOnTimeout(socket);
}
// Stops a timeout from triggering
function clearTimer() {
// Clear the timeout
if (self._timeout) {
clearTimeout(self._timeout);
self._timeout = null;
}
// Clean up all attached listeners
self.removeListener("abort", clearTimer);
self.removeListener("error", clearTimer);
self.removeListener("response", clearTimer);
self.removeListener("close", clearTimer);
if (callback) {
self.removeListener("timeout", callback);
}
if (!self.socket) {
self._currentRequest.removeListener("socket", startTimer);
}
}
// Attach callback if passed
if (callback) {
this.on("timeout", callback);
}
// Start the timer if or when the socket is opened
if (this.socket) {
startTimer(this.socket);
}
else {
this._currentRequest.once("socket", startTimer);
}
// Clean up on events
this.on("socket", destroyOnTimeout);
this.on("abort", clearTimer);
this.on("error", clearTimer);
this.on("response", clearTimer);
this.on("close", clearTimer);
return this;
};
// Proxy all other public ClientRequest methods
[
"flushHeaders", "getHeader",
"setNoDelay", "setSocketKeepAlive",
].forEach(function (method) {
RedirectableRequest.prototype[method] = function (a, b) {
return this._currentRequest[method](a, b);
};
});
// Proxy all public ClientRequest properties
["aborted", "connection", "socket"].forEach(function (property) {
Object.defineProperty(RedirectableRequest.prototype, property, {
get: function () { return this._currentRequest[property]; },
});
});
RedirectableRequest.prototype._sanitizeOptions = function (options) {
// Ensure headers are always present
if (!options.headers) {
options.headers = {};
}
// Since http.request treats host as an alias of hostname,
// but the url module interprets host as hostname plus port,
// eliminate the host property to avoid confusion.
if (options.host) {
// Use hostname if set, because it has precedence
if (!options.hostname) {
options.hostname = options.host;
}
delete options.host;
}
// Complete the URL object when necessary
if (!options.pathname && options.path) {
var searchPos = options.path.indexOf("?");
if (searchPos < 0) {
options.pathname = options.path;
}
else {
options.pathname = options.path.substring(0, searchPos);
options.search = options.path.substring(searchPos);
}
}
};
// Executes the next native request (initial or redirect)
RedirectableRequest.prototype._performRequest = function () {
// Load the native protocol
var protocol = this._options.protocol;
var nativeProtocol = this._options.nativeProtocols[protocol];
if (!nativeProtocol) {
this.emit("error", new TypeError("Unsupported protocol " + protocol));
return;
}
// If specified, use the agent corresponding to the protocol
// (HTTP and HTTPS use different types of agents)
if (this._options.agents) {
var scheme = protocol.slice(0, -1);
this._options.agent = this._options.agents[scheme];
}
// Create the native request and set up its event handlers
var request = this._currentRequest =
nativeProtocol.request(this._options, this._onNativeResponse);
request._redirectable = this;
for (var event of events) {
request.on(event, eventHandlers[event]);
}
// RFC7230§5.3.1: When making a request directly to an origin server, […]
// a client MUST send only the absolute path […] as the request-target.
this._currentUrl = /^\//.test(this._options.path) ?
url.format(this._options) :
// When making a request to a proxy, […]
// a client MUST send the target URI in absolute-form […].
this._options.path;
// End a redirected request
// (The first request must be ended explicitly with RedirectableRequest#end)
if (this._isRedirect) {
// Write the request entity and end
var i = 0;
var self = this;
var buffers = this._requestBodyBuffers;
(function writeNext(error) {
// Only write if this request has not been redirected yet
/* istanbul ignore else */
if (request === self._currentRequest) {
// Report any write errors
/* istanbul ignore if */
if (error) {
self.emit("error", error);
}
// Write the next buffer if there are still left
else if (i < buffers.length) {
var buffer = buffers[i++];
/* istanbul ignore else */
if (!request.finished) {
request.write(buffer.data, buffer.encoding, writeNext);
}
}
// End the request if `end` has been called on us
else if (self._ended) {
request.end();
}
}
}());
}
};
// Processes a response from the current native request
RedirectableRequest.prototype._processResponse = function (response) {
// Store the redirected response
var statusCode = response.statusCode;
if (this._options.trackRedirects) {
this._redirects.push({
url: this._currentUrl,
headers: response.headers,
statusCode: statusCode,
});
}
// RFC7231§6.4: The 3xx (Redirection) class of status code indicates
// that further action needs to be taken by the user agent in order to
// fulfill the request. If a Location header field is provided,
// the user agent MAY automatically redirect its request to the URI
// referenced by the Location field value,
// even if the specific status code is not understood.
// If the response is not a redirect; return it as-is
var location = response.headers.location;
if (!location || this._options.followRedirects === false ||
statusCode < 300 || statusCode >= 400) {
response.responseUrl = this._currentUrl;
response.redirects = this._redirects;
this.emit("response", response);
// Clean up
this._requestBodyBuffers = [];
return;
}
// The response is a redirect, so abort the current request
destroyRequest(this._currentRequest);
// Discard the remainder of the response to avoid waiting for data
response.destroy();
// RFC7231§6.4: A client SHOULD detect and intervene
// in cyclical redirections (i.e., "infinite" redirection loops).
if (++this._redirectCount > this._options.maxRedirects) {
this.emit("error", new TooManyRedirectsError());
return;
}
// Store the request headers if applicable
var requestHeaders;
var beforeRedirect = this._options.beforeRedirect;
if (beforeRedirect) {
requestHeaders = Object.assign({
// The Host header was set by nativeProtocol.request
Host: response.req.getHeader("host"),
}, this._options.headers);
}
// RFC7231§6.4: Automatic redirection needs to done with
// care for methods not known to be safe, […]
// RFC7231§6.4.2–3: For historical reasons, a user agent MAY change
// the request method from POST to GET for the subsequent request.
var method = this._options.method;
if ((statusCode === 301 || statusCode === 302) && this._options.method === "POST" ||
// RFC7231§6.4.4: The 303 (See Other) status code indicates that
// the server is redirecting the user agent to a different resource […]
// A user agent can perform a retrieval request targeting that URI
// (a GET or HEAD request if using HTTP) […]
(statusCode === 303) && !/^(?:GET|HEAD)$/.test(this._options.method)) {
this._options.method = "GET";
// Drop a possible entity and headers related to it
this._requestBodyBuffers = [];
removeMatchingHeaders(/^content-/i, this._options.headers);
}
// Drop the Host header, as the redirect might lead to a different host
var currentHostHeader = removeMatchingHeaders(/^host$/i, this._options.headers);
// If the redirect is relative, carry over the host of the last request
var currentUrlParts = url.parse(this._currentUrl);
var currentHost = currentHostHeader || currentUrlParts.host;
var currentUrl = /^\w+:/.test(location) ? this._currentUrl :
url.format(Object.assign(currentUrlParts, { host: currentHost }));
// Determine the URL of the redirection
var redirectUrl;
try {
redirectUrl = url.resolve(currentUrl, location);
}
catch (cause) {
this.emit("error", new RedirectionError({ cause: cause }));
return;
}
// Create the redirected request
debug("redirecting to", redirectUrl);
this._isRedirect = true;
var redirectUrlParts = url.parse(redirectUrl);
Object.assign(this._options, redirectUrlParts);
// Drop confidential headers when redirecting to a less secure protocol
// or to a different domain that is not a superdomain
if (redirectUrlParts.protocol !== currentUrlParts.protocol &&
redirectUrlParts.protocol !== "https:" ||
redirectUrlParts.host !== currentHost &&
!isSubdomain(redirectUrlParts.host, currentHost)) {
removeMatchingHeaders(/^(?:authorization|cookie)$/i, this._options.headers);
}
// Evaluate the beforeRedirect callback
if (isFunction(beforeRedirect)) {
var responseDetails = {
headers: response.headers,
statusCode: statusCode,
};
var requestDetails = {
url: currentUrl,
method: method,
headers: requestHeaders,
};
try {
beforeRedirect(this._options, responseDetails, requestDetails);
}
catch (err) {
this.emit("error", err);
return;
}
this._sanitizeOptions(this._options);
}
// Perform the redirected request
try {
this._performRequest();
}
catch (cause) {
this.emit("error", new RedirectionError({ cause: cause }));
}
};
// Wraps the key/value object of protocols with redirect functionality
function wrap(protocols) {
// Default settings
var exports = {
maxRedirects: 21,
maxBodyLength: 10 * 1024 * 1024,
};
// Wrap each protocol
var nativeProtocols = {};
Object.keys(protocols).forEach(function (scheme) {
var protocol = scheme + ":";
var nativeProtocol = nativeProtocols[protocol] = protocols[scheme];
var wrappedProtocol = exports[scheme] = Object.create(nativeProtocol);
// Executes a request, following redirects
function request(input, options, callback) {
// Parse parameters
if (isString(input)) {
var parsed;
try {
parsed = urlToOptions(new URL(input));
}
catch (err) {
/* istanbul ignore next */
parsed = url.parse(input);
}
if (!isString(parsed.protocol)) {
throw new InvalidUrlError({ input });
}
input = parsed;
}
else if (URL && (input instanceof URL)) {
input = urlToOptions(input);
}
else {
callback = options;
options = input;
input = { protocol: protocol };
}
if (isFunction(options)) {
callback = options;
options = null;
}
// Set defaults
options = Object.assign({
maxRedirects: exports.maxRedirects,
maxBodyLength: exports.maxBodyLength,
}, input, options);
options.nativeProtocols = nativeProtocols;
if (!isString(options.host) && !isString(options.hostname)) {
options.hostname = "::1";
}
assert.equal(options.protocol, protocol, "protocol mismatch");
debug("options", options);
return new RedirectableRequest(options, callback);
}
// Executes a GET request, following redirects
function get(input, options, callback) {
var wrappedRequest = wrappedProtocol.request(input, options, callback);
wrappedRequest.end();
return wrappedRequest;
}
// Expose the properties on the wrapped protocol
Object.defineProperties(wrappedProtocol, {
request: { value: request, configurable: true, enumerable: true, writable: true },
get: { value: get, configurable: true, enumerable: true, writable: true },
});
});
return exports;
}
/* istanbul ignore next */
function noop() { /* empty */ }
// from https://github.com/nodejs/node/blob/master/lib/internal/url.js
function urlToOptions(urlObject) {
var options = {
protocol: urlObject.protocol,
hostname: urlObject.hostname.startsWith("[") ?
/* istanbul ignore next */
urlObject.hostname.slice(1, -1) :
urlObject.hostname,
hash: urlObject.hash,
search: urlObject.search,
pathname: urlObject.pathname,
path: urlObject.pathname + urlObject.search,
href: urlObject.href,
};
if (urlObject.port !== "") {
options.port = Number(urlObject.port);
}
return options;
}
function removeMatchingHeaders(regex, headers) {
var lastValue;
for (var header in headers) {
if (regex.test(header)) {
lastValue = headers[header];
delete headers[header];
}
}
return (lastValue === null || typeof lastValue === "undefined") ?
undefined : String(lastValue).trim();
}
function createErrorType(code, message, baseClass) {
// Create constructor
function CustomError(properties) {
Error.captureStackTrace(this, this.constructor);
Object.assign(this, properties || {});
this.code = code;
this.message = this.cause ? message + ": " + this.cause.message : message;
}
// Attach constructor and set default properties
CustomError.prototype = new (baseClass || Error)();
CustomError.prototype.constructor = CustomError;
CustomError.prototype.name = "Error [" + code + "]";
return CustomError;
}
function destroyRequest(request, error) {
for (var event of events) {
request.removeListener(event, eventHandlers[event]);
}
request.on("error", noop);
request.destroy(error);
}
function isSubdomain(subdomain, domain) {
assert(isString(subdomain) && isString(domain));
var dot = subdomain.length - domain.length - 1;
return dot > 0 && subdomain[dot] === "." && subdomain.endsWith(domain);
}
function isString(value) {
return typeof value === "string" || value instanceof String;
}
function isFunction(value) {
return typeof value === "function";
}
function isBuffer(value) {
return typeof value === "object" && ("length" in value);
}
// Exports
module.exports = wrap({ http: http, https: https });
module.exports.wrap = wrap;