xunfeiAI/node_modules/follow-redirects/index.js

622 lines
18 KiB
JavaScript
Raw Permalink Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

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"
);
// 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 () {
abortRequest(this._currentRequest);
this.emit("abort");
};
// 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);
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);
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
abortRequest(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§6.4.23: 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 abortRequest(request) {
for (var event of events) {
request.removeListener(event, eventHandlers[event]);
}
request.on("error", noop);
request.abort();
}
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;