world/book/node_modules/unxhr/lib/XMLHttpRequest.js
2025-05-12 05:38:44 +09:00

599 lines
16 KiB
JavaScript

/**
* Wrapper for built-in http.js to emulate the browser XMLHttpRequest object.
*
* This can be used with JS designed for browsers to improve reuse of code and
* allow the use of existing libraries.
*
* Usage: include("XMLHttpRequest.js") and use XMLHttpRequest per W3C specs.
*
* @author Dan DeFelippi <dan@driverdan.com>
* @contributor David Ellis <d.f.ellis@ieee.org>
* @contributor Guillaume Grossetie <ggrossetie@yuzutech.fr>
* @license MIT
*/
const Url = require('url')
const fs = require('fs')
const path = require('path')
exports.XMLHttpRequest = function () {
'use strict'
/**
* Private variables
*/
const self = this
const http = require('http')
const https = require('https')
// Holds http.js objects
let request
let response
// Request settings
let settings = {}
// Disable header blacklist.
// Not part of XHR specs.
let disableHeaderCheck = false
// Set some default headers
const defaultHeaders = {
'User-Agent': 'node-XMLHttpRequest',
'Accept': '*/*'
}
let headers = {}
const headersCase = {}
// These headers are not user setable.
// The following are allowed but banned in the spec:
// * user-agent
const forbiddenRequestHeaders = [
'accept-charset',
'accept-encoding',
'access-control-request-headers',
'access-control-request-method',
'connection',
'content-length',
'content-transfer-encoding',
'cookie',
'cookie2',
'date',
'expect',
'host',
'keep-alive',
'origin',
'referer',
'te',
'trailer',
'transfer-encoding',
'upgrade',
'via'
]
// These request methods are not allowed
const forbiddenRequestMethods = [
'TRACE',
'TRACK',
'CONNECT'
]
// Send flag
let sendFlag = false
// Error flag, used when errors occur or abort is called
let errorFlag = false
// Event listeners
const listeners = {}
/**
* Constants
*/
this.UNSENT = 0
this.OPENED = 1
this.HEADERS_RECEIVED = 2
this.LOADING = 3
this.DONE = 4
/**
* Public vars
*/
// Current state
this.readyState = this.UNSENT
// default ready state change handler in case one is not set or is set late
this.onreadystatechange = null
// Result & response
this.responseText = ''
this.responseXML = ''
this.status = null
this.statusText = null
// Whether cross-site Access-Control requests should be made using
// credentials such as cookies or authorization headers
this.withCredentials = false
// "text", "arraybuffer", "blob", or "document", depending on your data needs.
// Note, setting xhr.responseType = '' (or omitting) will default the response to "text".
this.responseType = ''
/**
* Private methods
*/
/**
* Check if the specified header is allowed.
*
* @param header - {string} Header to validate
* @return {boolean} - False if not allowed, otherwise true
*/
const isAllowedHttpHeader = function (header) {
return disableHeaderCheck || (header && forbiddenRequestHeaders.indexOf(header.toLowerCase()) === -1)
}
/**
* Check if the specified method is allowed.
*
* @param method - {string} Request method to validate
* @return {boolean} - False if not allowed, otherwise true
*/
const isAllowedHttpMethod = function (method) {
return (method && forbiddenRequestMethods.indexOf(method) === -1)
}
/**
* Public methods
*/
/**
* Open the connection. Currently supports local server requests.
*
* @param method - {string} Connection method (eg GET, POST)
* @param url - {string} URL for the connection.
* @param async - {boolean} Asynchronous connection. Default is true.
* @param user - {string} Username for basic authentication (optional)
* @param password - {string} Password for basic authentication (optional)
*/
this.open = function (method, url, async, user, password) {
this.abort()
errorFlag = false
// Check for valid request method
if (!isAllowedHttpMethod(method)) {
throw new Error('SecurityError: Request method not allowed')
}
settings = {
'method': method,
'url': url.toString(),
'async': (typeof async !== 'boolean' ? true : async),
'user': user || null,
'password': password || null
}
setState(this.OPENED)
}
/**
* Disables or enables isAllowedHttpHeader() check the request. Enabled by default.
* This does not conform to the W3C spec.
*
* @param state - {boolean} Enable or disable header checking.
*/
this.setDisableHeaderCheck = function (state) {
disableHeaderCheck = state
}
/**
* Sets a header for the request or appends the value if one is already set.
*
* @param header - {string} Header name
* @param value - {string} Header value
*/
this.setRequestHeader = function (header, value) {
if (this.readyState !== this.OPENED) {
throw new Error('INVALID_STATE_ERR: setRequestHeader can only be called when state is OPEN')
}
if (!isAllowedHttpHeader(header)) {
console.warn('Refused to set unsafe header "' + header + '"')
return
}
if (sendFlag) {
throw new Error('INVALID_STATE_ERR: send flag is true')
}
header = headersCase[header.toLowerCase()] || header
headersCase[header.toLowerCase()] = header
headers[header] = headers[header] ? headers[header] + ', ' + value : value
}
/**
* Gets a header from the server response.
*
* @param header - {string} Name of header to get.
* @return {Object} - Text of the header or null if it doesn't exist.
*/
this.getResponseHeader = function (header) {
if (typeof header === 'string' &&
this.readyState > this.OPENED &&
response &&
response.headers &&
response.headers[header.toLowerCase()] &&
!errorFlag
) {
return response.headers[header.toLowerCase()]
}
return null
}
/**
* Gets all the response headers.
*
* @return string A string with all response headers separated by CR+LF
*/
this.getAllResponseHeaders = function () {
if (this.readyState < this.HEADERS_RECEIVED || errorFlag) {
return ''
}
let result = ''
for (let i in response.headers) {
// Cookie headers are excluded
if (i !== 'set-cookie' && i !== 'set-cookie2') {
result += i + ': ' + response.headers[i] + '\r\n'
}
}
return result.substr(0, result.length - 2)
}
/**
* Gets a request header
*
* @param name - {string} Name of header to get
* @return {string} Returns the request header or empty string if not set
*/
this.getRequestHeader = function (name) {
if (typeof name === 'string' && headersCase[name.toLowerCase()]) {
return headers[headersCase[name.toLowerCase()]]
}
return ''
}
/**
* Sends the request to the server.
*
* @param data - {string} Optional data to send as request body.
*/
this.send = function (data) {
if (this.readyState !== this.OPENED) {
throw new Error('INVALID_STATE_ERR: connection must be opened before send() is called')
}
if (sendFlag) {
throw new Error('INVALID_STATE_ERR: send has already been called')
}
let ssl = false
let local = false
const url = Url.parse(settings.url)
let host
// Determine the server
switch (url.protocol) {
case 'https:':
ssl = true
host = url.hostname
break
case 'http:':
host = url.hostname
break
case 'file:':
local = true
break
case undefined:
case null:
case '':
host = 'localhost'
break
default:
throw new Error('Protocol not supported.')
}
// Load files off the local filesystem (file://)
if (local) {
if (settings.method !== 'GET') {
throw new Error('XMLHttpRequest: Only GET method is supported')
}
if (settings.async) {
fs.readFile(url.pathname, 'utf8', function (error, data) {
if (error) {
self.handleError(error)
} else {
self.status = 200
self.responseText = data
setState(self.DONE)
}
})
} else {
try {
this.responseText = fs.readFileSync(url.pathname, 'utf8')
this.status = 200
setState(self.DONE)
} catch (e) {
this.handleError(e)
}
}
return
}
// Default to port 80. If accessing localhost on another port be sure
// to use http://localhost:port/path
const port = url.port || (ssl ? 443 : 80)
// Add query string if one is used
const uri = url.pathname + (url.search ? url.search : '')
// Set the defaults if they haven't been set
for (let name in defaultHeaders) {
if (!headersCase[name.toLowerCase()]) {
headers[name] = defaultHeaders[name]
}
}
// Set the Host header or the server may reject the request
headers.Host = host
// IPv6 addresses must be escaped with brackets
if (url.host[0] === '[') {
headers.Host = '[' + headers.Host + ']'
}
if (!((ssl && port === 443) || port === 80)) {
headers.Host += ':' + url.port
}
// Set Basic Auth if necessary
if (settings.user) {
if (typeof settings.password === 'undefined') {
settings.password = ''
}
const authBuf = Buffer.from(settings.user + ':' + settings.password)
headers.Authorization = 'Basic ' + authBuf.toString('base64')
}
// Set content length header
if (settings.method === 'GET' || settings.method === 'HEAD') {
data = null
} else if (data) {
headers['Content-Length'] = Buffer.isBuffer(data) ? data.length : Buffer.byteLength(data)
if (!this.getRequestHeader('Content-Type')) {
headers['Content-Type'] = 'text/plain;charset=UTF-8'
}
} else if (settings.method === 'POST') {
// For a post with no data set Content-Length: 0.
// This is required by buggy servers that don't meet the specs.
headers['Content-Length'] = 0
}
const options = {
host: host,
port: port,
path: uri,
method: settings.method,
headers: headers,
agent: false,
withCredentials: self.withCredentials
}
const responseType = this.responseType || 'text'
// Reset error flag
errorFlag = false
// Handle async requests
if (settings.async) {
// Use the proper protocol
var doRequest = ssl ? https.request : http.request
// Request is being sent, set send flag
sendFlag = true
// As per spec, this is called here for historical reasons.
self.dispatchEvent('readystatechange')
// Handler for the response
const responseHandler = function responseHandler (resp) {
// Set response var to the response we got back
// This is so it remains accessable outside this scope
response = resp
// Check for redirect
// @TODO Prevent looped redirects
if (response.statusCode === 301 || response.statusCode === 302 || response.statusCode === 303 || response.statusCode === 307) {
// Change URL to the redirect location
settings.url = response.headers.location
const url = Url.parse(settings.url)
// Set host var in case it's used later
host = url.hostname
// Options for the new request
const newOptions = {
hostname: url.hostname,
port: url.port,
path: url.path,
method: response.statusCode === 303 ? 'GET' : settings.method,
headers: headers,
withCredentials: self.withCredentials
}
// Issue the new request
request = doRequest(newOptions, responseHandler).on('error', errorHandler)
request.end()
// @TODO Check if an XHR event needs to be fired here
return
}
response.setEncoding('utf8')
setState(self.HEADERS_RECEIVED)
self.status = response.statusCode
response.on('data', function (chunk) {
// Make sure there's some data
if (chunk) {
self.responseText += chunk
}
// Don't emit state changes if the connection has been aborted.
if (sendFlag) {
setState(self.LOADING)
}
})
response.on('end', function () {
if (sendFlag) {
// Discard the end event if the connection has been aborted
setState(self.DONE)
sendFlag = false
}
})
response.on('error', function (error) {
self.handleError(error)
})
}
// Error handler for the request
const errorHandler = function errorHandler (error) {
self.handleError(error)
}
// Create the request
request = doRequest(options, responseHandler).on('error', errorHandler)
// Node 0.4 and later won't accept empty data. Make sure it's needed.
if (data) {
request.write(data)
}
request.end()
self.dispatchEvent('loadstart')
} else { // Synchronous
const encoding = responseType === 'text' ? 'utf8' : 'binary'
const output = require('child_process').execSync(`"${process.argv[0]}" "${__dirname}/request.js" \
--ssl="${ssl}" \
--encoding="${encoding}" \
--request-options=${JSON.stringify(JSON.stringify(options))}`, { stdio: 'pipe' })
const result = JSON.parse(output.toString('utf8'))
if (result.error) {
self.handleError(result.error)
} else {
response = result.data
self.status = result.data.statusCode
if (encoding === 'binary') {
self.response = Uint8Array.from(result.data.binary.data).buffer
} else {
self.responseText = result.data.text
}
setState(self.DONE)
}
}
}
/**
* Called when an error is encountered to deal with it.
*/
this.handleError = function (error) {
this.status = 0
this.statusText = error
this.responseText = error.stack
errorFlag = true
setState(this.DONE)
this.dispatchEvent('error')
}
/**
* Aborts a request.
*/
this.abort = function () {
if (request) {
request.abort()
request = null
}
headers = defaultHeaders
this.status = 0
this.responseText = ''
this.responseXML = ''
errorFlag = true
if (this.readyState !== this.UNSENT &&
(this.readyState !== this.OPENED || sendFlag) &&
this.readyState !== this.DONE) {
sendFlag = false
setState(this.DONE)
}
this.readyState = this.UNSENT
this.dispatchEvent('abort')
}
/**
* Adds an event listener. Preferred method of binding to events.
*/
this.addEventListener = function (event, callback) {
if (!(event in listeners)) {
listeners[event] = []
}
// Currently allows duplicate callbacks. Should it?
listeners[event].push(callback)
}
/**
* Remove an event callback that has already been bound.
* Only works on the matching funciton, cannot be a copy.
*/
this.removeEventListener = function (event, callback) {
if (event in listeners) {
// Filter will return a new array with the callback removed
listeners[event] = listeners[event].filter(function (ev) {
return ev !== callback
})
}
}
/**
* Dispatch any events, including both "on" methods and events attached using addEventListener.
*/
this.dispatchEvent = function (event) {
if (typeof self['on' + event] === 'function') {
self['on' + event]()
}
if (event in listeners) {
for (let i = 0, len = listeners[event].length; i < len; i++) {
listeners[event][i].call(self)
}
}
}
/**
* Changes readyState and calls onreadystatechange.
*
* @param state - {Number} New state
*/
const setState = function (state) {
if (state === self.LOADING || self.readyState !== state) {
self.readyState = state
if (settings.async || self.readyState < self.OPENED || self.readyState === self.DONE) {
self.dispatchEvent('readystatechange')
}
if (self.readyState === self.DONE && !errorFlag) {
self.dispatchEvent('load')
// @TODO figure out InspectorInstrumentation::didLoadXHR(cookie)
self.dispatchEvent('loadend')
}
}
}
}