twitst4tz

index.mjs (40866B)

---

 import Stream from 'stream';
 import http from 'http';
 import Url from 'url';
 import https from 'https';
 import zlib from 'zlib';
 
 // Based on https://github.com/tmpvar/jsdom/blob/aa85b2abf07766ff7bf5c1f6daafb3726f2f2db5/lib/jsdom/living/blob.js
 
 // fix for "Readable" isn't a named export issue
 const Readable = Stream.Readable;
 
 const BUFFER = Symbol('buffer');
 const TYPE = Symbol('type');
 
 class Blob {
 	constructor() {
 		this[TYPE] = '';
 
 		const blobParts = arguments[0];
 		const options = arguments[1];
 
 		const buffers = [];
 		let size = 0;
 
 		if (blobParts) {
 			const a = blobParts;
 			const length = Number(a.length);
 			for (let i = 0; i < length; i++) {
 				const element = a[i];
 				let buffer;
 				if (element instanceof Buffer) {
 					buffer = element;
 				} else if (ArrayBuffer.isView(element)) {
 					buffer = Buffer.from(element.buffer, element.byteOffset, element.byteLength);
 				} else if (element instanceof ArrayBuffer) {
 					buffer = Buffer.from(element);
 				} else if (element instanceof Blob) {
 					buffer = element[BUFFER];
 				} else {
 					buffer = Buffer.from(typeof element === 'string' ? element : String(element));
 				}
 				size += buffer.length;
 				buffers.push(buffer);
 			}
 		}
 
 		this[BUFFER] = Buffer.concat(buffers);
 
 		let type = options && options.type !== undefined && String(options.type).toLowerCase();
 		if (type && !/[^\u0020-\u007E]/.test(type)) {
 			this[TYPE] = type;
 		}
 	}
 	get size() {
 		return this[BUFFER].length;
 	}
 	get type() {
 		return this[TYPE];
 	}
 	text() {
 		return Promise.resolve(this[BUFFER].toString());
 	}
 	arrayBuffer() {
 		const buf = this[BUFFER];
 		const ab = buf.buffer.slice(buf.byteOffset, buf.byteOffset + buf.byteLength);
 		return Promise.resolve(ab);
 	}
 	stream() {
 		const readable = new Readable();
 		readable._read = function () {};
 		readable.push(this[BUFFER]);
 		readable.push(null);
 		return readable;
 	}
 	toString() {
 		return '[object Blob]';
 	}
 	slice() {
 		const size = this.size;
 
 		const start = arguments[0];
 		const end = arguments[1];
 		let relativeStart, relativeEnd;
 		if (start === undefined) {
 			relativeStart = 0;
 		} else if (start < 0) {
 			relativeStart = Math.max(size + start, 0);
 		} else {
 			relativeStart = Math.min(start, size);
 		}
 		if (end === undefined) {
 			relativeEnd = size;
 		} else if (end < 0) {
 			relativeEnd = Math.max(size + end, 0);
 		} else {
 			relativeEnd = Math.min(end, size);
 		}
 		const span = Math.max(relativeEnd - relativeStart, 0);
 
 		const buffer = this[BUFFER];
 		const slicedBuffer = buffer.slice(relativeStart, relativeStart + span);
 		const blob = new Blob([], { type: arguments[2] });
 		blob[BUFFER] = slicedBuffer;
 		return blob;
 	}
 }
 
 Object.defineProperties(Blob.prototype, {
 	size: { enumerable: true },
 	type: { enumerable: true },
 	slice: { enumerable: true }
 });
 
 Object.defineProperty(Blob.prototype, Symbol.toStringTag, {
 	value: 'Blob',
 	writable: false,
 	enumerable: false,
 	configurable: true
 });
 
 /**
  * fetch-error.js
  *
  * FetchError interface for operational errors
  */
 
 /**
  * Create FetchError instance
  *
  * @param   String      message      Error message for human
  * @param   String      type         Error type for machine
  * @param   String      systemError  For Node.js system error
  * @return  FetchError
  */
 function FetchError(message, type, systemError) {
   Error.call(this, message);
 
   this.message = message;
   this.type = type;
 
   // when err.type is `system`, err.code contains system error code
   if (systemError) {
     this.code = this.errno = systemError.code;
   }
 
   // hide custom error implementation details from end-users
   Error.captureStackTrace(this, this.constructor);
 }
 
 FetchError.prototype = Object.create(Error.prototype);
 FetchError.prototype.constructor = FetchError;
 FetchError.prototype.name = 'FetchError';
 
 let convert;
 try {
 	convert = require('encoding').convert;
 } catch (e) {}
 
 const INTERNALS = Symbol('Body internals');
 
 // fix an issue where "PassThrough" isn't a named export for node <10
 const PassThrough = Stream.PassThrough;
 
 /**
  * Body mixin
  *
  * Ref: https://fetch.spec.whatwg.org/#body
  *
  * @param   Stream  body  Readable stream
  * @param   Object  opts  Response options
  * @return  Void
  */
 function Body(body) {
 	var _this = this;
 
 	var _ref = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {},
 	    _ref$size = _ref.size;
 
 	let size = _ref$size === undefined ? 0 : _ref$size;
 	var _ref$timeout = _ref.timeout;
 	let timeout = _ref$timeout === undefined ? 0 : _ref$timeout;
 
 	if (body == null) {
 		// body is undefined or null
 		body = null;
 	} else if (isURLSearchParams(body)) {
 		// body is a URLSearchParams
 		body = Buffer.from(body.toString());
 	} else if (isBlob(body)) ; else if (Buffer.isBuffer(body)) ; else if (Object.prototype.toString.call(body) === '[object ArrayBuffer]') {
 		// body is ArrayBuffer
 		body = Buffer.from(body);
 	} else if (ArrayBuffer.isView(body)) {
 		// body is ArrayBufferView
 		body = Buffer.from(body.buffer, body.byteOffset, body.byteLength);
 	} else if (body instanceof Stream) ; else {
 		// none of the above
 		// coerce to string then buffer
 		body = Buffer.from(String(body));
 	}
 	this[INTERNALS] = {
 		body,
 		disturbed: false,
 		error: null
 	};
 	this.size = size;
 	this.timeout = timeout;
 
 	if (body instanceof Stream) {
 		body.on('error', function (err) {
 			const error = err.name === 'AbortError' ? err : new FetchError(`Invalid response body while trying to fetch ${_this.url}: ${err.message}`, 'system', err);
 			_this[INTERNALS].error = error;
 		});
 	}
 }
 
 Body.prototype = {
 	get body() {
 		return this[INTERNALS].body;
 	},
 
 	get bodyUsed() {
 		return this[INTERNALS].disturbed;
 	},
 
 	/**
   * Decode response as ArrayBuffer
   *
   * @return  Promise
   */
 	arrayBuffer() {
 		return consumeBody.call(this).then(function (buf) {
 			return buf.buffer.slice(buf.byteOffset, buf.byteOffset + buf.byteLength);
 		});
 	},
 
 	/**
   * Return raw response as Blob
   *
   * @return Promise
   */
 	blob() {
 		let ct = this.headers && this.headers.get('content-type') || '';
 		return consumeBody.call(this).then(function (buf) {
 			return Object.assign(
 			// Prevent copying
 			new Blob([], {
 				type: ct.toLowerCase()
 			}), {
 				[BUFFER]: buf
 			});
 		});
 	},
 
 	/**
   * Decode response as json
   *
   * @return  Promise
   */
 	json() {
 		var _this2 = this;
 
 		return consumeBody.call(this).then(function (buffer) {
 			try {
 				return JSON.parse(buffer.toString());
 			} catch (err) {
 				return Body.Promise.reject(new FetchError(`invalid json response body at ${_this2.url} reason: ${err.message}`, 'invalid-json'));
 			}
 		});
 	},
 
 	/**
   * Decode response as text
   *
   * @return  Promise
   */
 	text() {
 		return consumeBody.call(this).then(function (buffer) {
 			return buffer.toString();
 		});
 	},
 
 	/**
   * Decode response as buffer (non-spec api)
   *
   * @return  Promise
   */
 	buffer() {
 		return consumeBody.call(this);
 	},
 
 	/**
   * Decode response as text, while automatically detecting the encoding and
   * trying to decode to UTF-8 (non-spec api)
   *
   * @return  Promise
   */
 	textConverted() {
 		var _this3 = this;
 
 		return consumeBody.call(this).then(function (buffer) {
 			return convertBody(buffer, _this3.headers);
 		});
 	}
 };
 
 // In browsers, all properties are enumerable.
 Object.defineProperties(Body.prototype, {
 	body: { enumerable: true },
 	bodyUsed: { enumerable: true },
 	arrayBuffer: { enumerable: true },
 	blob: { enumerable: true },
 	json: { enumerable: true },
 	text: { enumerable: true }
 });
 
 Body.mixIn = function (proto) {
 	for (const name of Object.getOwnPropertyNames(Body.prototype)) {
 		// istanbul ignore else: future proof
 		if (!(name in proto)) {
 			const desc = Object.getOwnPropertyDescriptor(Body.prototype, name);
 			Object.defineProperty(proto, name, desc);
 		}
 	}
 };
 
 /**
  * Consume and convert an entire Body to a Buffer.
  *
  * Ref: https://fetch.spec.whatwg.org/#concept-body-consume-body
  *
  * @return  Promise
  */
 function consumeBody() {
 	var _this4 = this;
 
 	if (this[INTERNALS].disturbed) {
 		return Body.Promise.reject(new TypeError(`body used already for: ${this.url}`));
 	}
 
 	this[INTERNALS].disturbed = true;
 
 	if (this[INTERNALS].error) {
 		return Body.Promise.reject(this[INTERNALS].error);
 	}
 
 	let body = this.body;
 
 	// body is null
 	if (body === null) {
 		return Body.Promise.resolve(Buffer.alloc(0));
 	}
 
 	// body is blob
 	if (isBlob(body)) {
 		body = body.stream();
 	}
 
 	// body is buffer
 	if (Buffer.isBuffer(body)) {
 		return Body.Promise.resolve(body);
 	}
 
 	// istanbul ignore if: should never happen
 	if (!(body instanceof Stream)) {
 		return Body.Promise.resolve(Buffer.alloc(0));
 	}
 
 	// body is stream
 	// get ready to actually consume the body
 	let accum = [];
 	let accumBytes = 0;
 	let abort = false;
 
 	return new Body.Promise(function (resolve, reject) {
 		let resTimeout;
 
 		// allow timeout on slow response body
 		if (_this4.timeout) {
 			resTimeout = setTimeout(function () {
 				abort = true;
 				reject(new FetchError(`Response timeout while trying to fetch ${_this4.url} (over ${_this4.timeout}ms)`, 'body-timeout'));
 			}, _this4.timeout);
 		}
 
 		// handle stream errors
 		body.on('error', function (err) {
 			if (err.name === 'AbortError') {
 				// if the request was aborted, reject with this Error
 				abort = true;
 				reject(err);
 			} else {
 				// other errors, such as incorrect content-encoding
 				reject(new FetchError(`Invalid response body while trying to fetch ${_this4.url}: ${err.message}`, 'system', err));
 			}
 		});
 
 		body.on('data', function (chunk) {
 			if (abort || chunk === null) {
 				return;
 			}
 
 			if (_this4.size && accumBytes + chunk.length > _this4.size) {
 				abort = true;
 				reject(new FetchError(`content size at ${_this4.url} over limit: ${_this4.size}`, 'max-size'));
 				return;
 			}
 
 			accumBytes += chunk.length;
 			accum.push(chunk);
 		});
 
 		body.on('end', function () {
 			if (abort) {
 				return;
 			}
 
 			clearTimeout(resTimeout);
 
 			try {
 				resolve(Buffer.concat(accum, accumBytes));
 			} catch (err) {
 				// handle streams that have accumulated too much data (issue #414)
 				reject(new FetchError(`Could not create Buffer from response body for ${_this4.url}: ${err.message}`, 'system', err));
 			}
 		});
 	});
 }
 
 /**
  * Detect buffer encoding and convert to target encoding
  * ref: http://www.w3.org/TR/2011/WD-html5-20110113/parsing.html#determining-the-character-encoding
  *
  * @param   Buffer  buffer    Incoming buffer
  * @param   String  encoding  Target encoding
  * @return  String
  */
 function convertBody(buffer, headers) {
 	if (typeof convert !== 'function') {
 		throw new Error('The package `encoding` must be installed to use the textConverted() function');
 	}
 
 	const ct = headers.get('content-type');
 	let charset = 'utf-8';
 	let res, str;
 
 	// header
 	if (ct) {
 		res = /charset=([^;]*)/i.exec(ct);
 	}
 
 	// no charset in content type, peek at response body for at most 1024 bytes
 	str = buffer.slice(0, 1024).toString();
 
 	// html5
 	if (!res && str) {
 		res = /<meta.+?charset=(['"])(.+?)\1/i.exec(str);
 	}
 
 	// html4
 	if (!res && str) {
 		res = /<meta[\s]+?http-equiv=(['"])content-type\1[\s]+?content=(['"])(.+?)\2/i.exec(str);
 
 		if (res) {
 			res = /charset=(.*)/i.exec(res.pop());
 		}
 	}
 
 	// xml
 	if (!res && str) {
 		res = /<\?xml.+?encoding=(['"])(.+?)\1/i.exec(str);
 	}
 
 	// found charset
 	if (res) {
 		charset = res.pop();
 
 		// prevent decode issues when sites use incorrect encoding
 		// ref: https://hsivonen.fi/encoding-menu/
 		if (charset === 'gb2312' || charset === 'gbk') {
 			charset = 'gb18030';
 		}
 	}
 
 	// turn raw buffers into a single utf-8 buffer
 	return convert(buffer, 'UTF-8', charset).toString();
 }
 
 /**
  * Detect a URLSearchParams object
  * ref: https://github.com/bitinn/node-fetch/issues/296#issuecomment-307598143
  *
  * @param   Object  obj     Object to detect by type or brand
  * @return  String
  */
 function isURLSearchParams(obj) {
 	// Duck-typing as a necessary condition.
 	if (typeof obj !== 'object' || typeof obj.append !== 'function' || typeof obj.delete !== 'function' || typeof obj.get !== 'function' || typeof obj.getAll !== 'function' || typeof obj.has !== 'function' || typeof obj.set !== 'function') {
 		return false;
 	}
 
 	// Brand-checking and more duck-typing as optional condition.
 	return obj.constructor.name === 'URLSearchParams' || Object.prototype.toString.call(obj) === '[object URLSearchParams]' || typeof obj.sort === 'function';
 }
 
 /**
  * Check if `obj` is a W3C `Blob` object (which `File` inherits from)
  * @param  {*} obj
  * @return {boolean}
  */
 function isBlob(obj) {
 	return typeof obj === 'object' && typeof obj.arrayBuffer === 'function' && typeof obj.type === 'string' && typeof obj.stream === 'function' && typeof obj.constructor === 'function' && typeof obj.constructor.name === 'string' && /^(Blob|File)$/.test(obj.constructor.name) && /^(Blob|File)$/.test(obj[Symbol.toStringTag]);
 }
 
 /**
  * Clone body given Res/Req instance
  *
  * @param   Mixed  instance  Response or Request instance
  * @return  Mixed
  */
 function clone(instance) {
 	let p1, p2;
 	let body = instance.body;
 
 	// don't allow cloning a used body
 	if (instance.bodyUsed) {
 		throw new Error('cannot clone body after it is used');
 	}
 
 	// check that body is a stream and not form-data object
 	// note: we can't clone the form-data object without having it as a dependency
 	if (body instanceof Stream && typeof body.getBoundary !== 'function') {
 		// tee instance body
 		p1 = new PassThrough();
 		p2 = new PassThrough();
 		body.pipe(p1);
 		body.pipe(p2);
 		// set instance body to teed body and return the other teed body
 		instance[INTERNALS].body = p1;
 		body = p2;
 	}
 
 	return body;
 }
 
 /**
  * Performs the operation "extract a `Content-Type` value from |object|" as
  * specified in the specification:
  * https://fetch.spec.whatwg.org/#concept-bodyinit-extract
  *
  * This function assumes that instance.body is present.
  *
  * @param   Mixed  instance  Any options.body input
  */
 function extractContentType(body) {
 	if (body === null) {
 		// body is null
 		return null;
 	} else if (typeof body === 'string') {
 		// body is string
 		return 'text/plain;charset=UTF-8';
 	} else if (isURLSearchParams(body)) {
 		// body is a URLSearchParams
 		return 'application/x-www-form-urlencoded;charset=UTF-8';
 	} else if (isBlob(body)) {
 		// body is blob
 		return body.type || null;
 	} else if (Buffer.isBuffer(body)) {
 		// body is buffer
 		return null;
 	} else if (Object.prototype.toString.call(body) === '[object ArrayBuffer]') {
 		// body is ArrayBuffer
 		return null;
 	} else if (ArrayBuffer.isView(body)) {
 		// body is ArrayBufferView
 		return null;
 	} else if (typeof body.getBoundary === 'function') {
 		// detect form data input from form-data module
 		return `multipart/form-data;boundary=${body.getBoundary()}`;
 	} else if (body instanceof Stream) {
 		// body is stream
 		// can't really do much about this
 		return null;
 	} else {
 		// Body constructor defaults other things to string
 		return 'text/plain;charset=UTF-8';
 	}
 }
 
 /**
  * The Fetch Standard treats this as if "total bytes" is a property on the body.
  * For us, we have to explicitly get it with a function.
  *
  * ref: https://fetch.spec.whatwg.org/#concept-body-total-bytes
  *
  * @param   Body    instance   Instance of Body
  * @return  Number?            Number of bytes, or null if not possible
  */
 function getTotalBytes(instance) {
 	const body = instance.body;
 
 
 	if (body === null) {
 		// body is null
 		return 0;
 	} else if (isBlob(body)) {
 		return body.size;
 	} else if (Buffer.isBuffer(body)) {
 		// body is buffer
 		return body.length;
 	} else if (body && typeof body.getLengthSync === 'function') {
 		// detect form data input from form-data module
 		if (body._lengthRetrievers && body._lengthRetrievers.length == 0 || // 1.x
 		body.hasKnownLength && body.hasKnownLength()) {
 			// 2.x
 			return body.getLengthSync();
 		}
 		return null;
 	} else {
 		// body is stream
 		return null;
 	}
 }
 
 /**
  * Write a Body to a Node.js WritableStream (e.g. http.Request) object.
  *
  * @param   Body    instance   Instance of Body
  * @return  Void
  */
 function writeToStream(dest, instance) {
 	const body = instance.body;
 
 
 	if (body === null) {
 		// body is null
 		dest.end();
 	} else if (isBlob(body)) {
 		body.stream().pipe(dest);
 	} else if (Buffer.isBuffer(body)) {
 		// body is buffer
 		dest.write(body);
 		dest.end();
 	} else {
 		// body is stream
 		body.pipe(dest);
 	}
 }
 
 // expose Promise
 Body.Promise = global.Promise;
 
 /**
  * headers.js
  *
  * Headers class offers convenient helpers
  */
 
 const invalidTokenRegex = /[^\^_`a-zA-Z\-0-9!#$%&'*+.|~]/;
 const invalidHeaderCharRegex = /[^\t\x20-\x7e\x80-\xff]/;
 
 function validateName(name) {
 	name = `${name}`;
 	if (invalidTokenRegex.test(name) || name === '') {
 		throw new TypeError(`${name} is not a legal HTTP header name`);
 	}
 }
 
 function validateValue(value) {
 	value = `${value}`;
 	if (invalidHeaderCharRegex.test(value)) {
 		throw new TypeError(`${value} is not a legal HTTP header value`);
 	}
 }
 
 /**
  * Find the key in the map object given a header name.
  *
  * Returns undefined if not found.
  *
  * @param   String  name  Header name
  * @return  String|Undefined
  */
 function find(map, name) {
 	name = name.toLowerCase();
 	for (const key in map) {
 		if (key.toLowerCase() === name) {
 			return key;
 		}
 	}
 	return undefined;
 }
 
 const MAP = Symbol('map');
 class Headers {
 	/**
   * Headers class
   *
   * @param   Object  headers  Response headers
   * @return  Void
   */
 	constructor() {
 		let init = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : undefined;
 
 		this[MAP] = Object.create(null);
 
 		if (init instanceof Headers) {
 			const rawHeaders = init.raw();
 			const headerNames = Object.keys(rawHeaders);
 
 			for (const headerName of headerNames) {
 				for (const value of rawHeaders[headerName]) {
 					this.append(headerName, value);
 				}
 			}
 
 			return;
 		}
 
 		// We don't worry about converting prop to ByteString here as append()
 		// will handle it.
 		if (init == null) ; else if (typeof init === 'object') {
 			const method = init[Symbol.iterator];
 			if (method != null) {
 				if (typeof method !== 'function') {
 					throw new TypeError('Header pairs must be iterable');
 				}
 
 				// sequence<sequence<ByteString>>
 				// Note: per spec we have to first exhaust the lists then process them
 				const pairs = [];
 				for (const pair of init) {
 					if (typeof pair !== 'object' || typeof pair[Symbol.iterator] !== 'function') {
 						throw new TypeError('Each header pair must be iterable');
 					}
 					pairs.push(Array.from(pair));
 				}
 
 				for (const pair of pairs) {
 					if (pair.length !== 2) {
 						throw new TypeError('Each header pair must be a name/value tuple');
 					}
 					this.append(pair[0], pair[1]);
 				}
 			} else {
 				// record<ByteString, ByteString>
 				for (const key of Object.keys(init)) {
 					const value = init[key];
 					this.append(key, value);
 				}
 			}
 		} else {
 			throw new TypeError('Provided initializer must be an object');
 		}
 	}
 
 	/**
   * Return combined header value given name
   *
   * @param   String  name  Header name
   * @return  Mixed
   */
 	get(name) {
 		name = `${name}`;
 		validateName(name);
 		const key = find(this[MAP], name);
 		if (key === undefined) {
 			return null;
 		}
 
 		return this[MAP][key].join(', ');
 	}
 
 	/**
   * Iterate over all headers
   *
   * @param   Function  callback  Executed for each item with parameters (value, name, thisArg)
   * @param   Boolean   thisArg   `this` context for callback function
   * @return  Void
   */
 	forEach(callback) {
 		let thisArg = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : undefined;
 
 		let pairs = getHeaders(this);
 		let i = 0;
 		while (i < pairs.length) {
 			var _pairs$i = pairs[i];
 			const name = _pairs$i[0],
 			      value = _pairs$i[1];
 
 			callback.call(thisArg, value, name, this);
 			pairs = getHeaders(this);
 			i++;
 		}
 	}
 
 	/**
   * Overwrite header values given name
   *
   * @param   String  name   Header name
   * @param   String  value  Header value
   * @return  Void
   */
 	set(name, value) {
 		name = `${name}`;
 		value = `${value}`;
 		validateName(name);
 		validateValue(value);
 		const key = find(this[MAP], name);
 		this[MAP][key !== undefined ? key : name] = [value];
 	}
 
 	/**
   * Append a value onto existing header
   *
   * @param   String  name   Header name
   * @param   String  value  Header value
   * @return  Void
   */
 	append(name, value) {
 		name = `${name}`;
 		value = `${value}`;
 		validateName(name);
 		validateValue(value);
 		const key = find(this[MAP], name);
 		if (key !== undefined) {
 			this[MAP][key].push(value);
 		} else {
 			this[MAP][name] = [value];
 		}
 	}
 
 	/**
   * Check for header name existence
   *
   * @param   String   name  Header name
   * @return  Boolean
   */
 	has(name) {
 		name = `${name}`;
 		validateName(name);
 		return find(this[MAP], name) !== undefined;
 	}
 
 	/**
   * Delete all header values given name
   *
   * @param   String  name  Header name
   * @return  Void
   */
 	delete(name) {
 		name = `${name}`;
 		validateName(name);
 		const key = find(this[MAP], name);
 		if (key !== undefined) {
 			delete this[MAP][key];
 		}
 	}
 
 	/**
   * Return raw headers (non-spec api)
   *
   * @return  Object
   */
 	raw() {
 		return this[MAP];
 	}
 
 	/**
   * Get an iterator on keys.
   *
   * @return  Iterator
   */
 	keys() {
 		return createHeadersIterator(this, 'key');
 	}
 
 	/**
   * Get an iterator on values.
   *
   * @return  Iterator
   */
 	values() {
 		return createHeadersIterator(this, 'value');
 	}
 
 	/**
   * Get an iterator on entries.
   *
   * This is the default iterator of the Headers object.
   *
   * @return  Iterator
   */
 	[Symbol.iterator]() {
 		return createHeadersIterator(this, 'key+value');
 	}
 }
 Headers.prototype.entries = Headers.prototype[Symbol.iterator];
 
 Object.defineProperty(Headers.prototype, Symbol.toStringTag, {
 	value: 'Headers',
 	writable: false,
 	enumerable: false,
 	configurable: true
 });
 
 Object.defineProperties(Headers.prototype, {
 	get: { enumerable: true },
 	forEach: { enumerable: true },
 	set: { enumerable: true },
 	append: { enumerable: true },
 	has: { enumerable: true },
 	delete: { enumerable: true },
 	keys: { enumerable: true },
 	values: { enumerable: true },
 	entries: { enumerable: true }
 });
 
 function getHeaders(headers) {
 	let kind = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : 'key+value';
 
 	const keys = Object.keys(headers[MAP]).sort();
 	return keys.map(kind === 'key' ? function (k) {
 		return k.toLowerCase();
 	} : kind === 'value' ? function (k) {
 		return headers[MAP][k].join(', ');
 	} : function (k) {
 		return [k.toLowerCase(), headers[MAP][k].join(', ')];
 	});
 }
 
 const INTERNAL = Symbol('internal');
 
 function createHeadersIterator(target, kind) {
 	const iterator = Object.create(HeadersIteratorPrototype);
 	iterator[INTERNAL] = {
 		target,
 		kind,
 		index: 0
 	};
 	return iterator;
 }
 
 const HeadersIteratorPrototype = Object.setPrototypeOf({
 	next() {
 		// istanbul ignore if
 		if (!this || Object.getPrototypeOf(this) !== HeadersIteratorPrototype) {
 			throw new TypeError('Value of `this` is not a HeadersIterator');
 		}
 
 		var _INTERNAL = this[INTERNAL];
 		const target = _INTERNAL.target,
 		      kind = _INTERNAL.kind,
 		      index = _INTERNAL.index;
 
 		const values = getHeaders(target, kind);
 		const len = values.length;
 		if (index >= len) {
 			return {
 				value: undefined,
 				done: true
 			};
 		}
 
 		this[INTERNAL].index = index + 1;
 
 		return {
 			value: values[index],
 			done: false
 		};
 	}
 }, Object.getPrototypeOf(Object.getPrototypeOf([][Symbol.iterator]())));
 
 Object.defineProperty(HeadersIteratorPrototype, Symbol.toStringTag, {
 	value: 'HeadersIterator',
 	writable: false,
 	enumerable: false,
 	configurable: true
 });
 
 /**
  * Export the Headers object in a form that Node.js can consume.
  *
  * @param   Headers  headers
  * @return  Object
  */
 function exportNodeCompatibleHeaders(headers) {
 	const obj = Object.assign({ __proto__: null }, headers[MAP]);
 
 	// http.request() only supports string as Host header. This hack makes
 	// specifying custom Host header possible.
 	const hostHeaderKey = find(headers[MAP], 'Host');
 	if (hostHeaderKey !== undefined) {
 		obj[hostHeaderKey] = obj[hostHeaderKey][0];
 	}
 
 	return obj;
 }
 
 /**
  * Create a Headers object from an object of headers, ignoring those that do
  * not conform to HTTP grammar productions.
  *
  * @param   Object  obj  Object of headers
  * @return  Headers
  */
 function createHeadersLenient(obj) {
 	const headers = new Headers();
 	for (const name of Object.keys(obj)) {
 		if (invalidTokenRegex.test(name)) {
 			continue;
 		}
 		if (Array.isArray(obj[name])) {
 			for (const val of obj[name]) {
 				if (invalidHeaderCharRegex.test(val)) {
 					continue;
 				}
 				if (headers[MAP][name] === undefined) {
 					headers[MAP][name] = [val];
 				} else {
 					headers[MAP][name].push(val);
 				}
 			}
 		} else if (!invalidHeaderCharRegex.test(obj[name])) {
 			headers[MAP][name] = [obj[name]];
 		}
 	}
 	return headers;
 }
 
 const INTERNALS$1 = Symbol('Response internals');
 
 // fix an issue where "STATUS_CODES" aren't a named export for node <10
 const STATUS_CODES = http.STATUS_CODES;
 
 /**
  * Response class
  *
  * @param   Stream  body  Readable stream
  * @param   Object  opts  Response options
  * @return  Void
  */
 class Response {
 	constructor() {
 		let body = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : null;
 		let opts = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};
 
 		Body.call(this, body, opts);
 
 		const status = opts.status || 200;
 		const headers = new Headers(opts.headers);
 
 		if (body != null && !headers.has('Content-Type')) {
 			const contentType = extractContentType(body);
 			if (contentType) {
 				headers.append('Content-Type', contentType);
 			}
 		}
 
 		this[INTERNALS$1] = {
 			url: opts.url,
 			status,
 			statusText: opts.statusText || STATUS_CODES[status],
 			headers,
 			counter: opts.counter
 		};
 	}
 
 	get url() {
 		return this[INTERNALS$1].url || '';
 	}
 
 	get status() {
 		return this[INTERNALS$1].status;
 	}
 
 	/**
   * Convenience property representing if the request ended normally
   */
 	get ok() {
 		return this[INTERNALS$1].status >= 200 && this[INTERNALS$1].status < 300;
 	}
 
 	get redirected() {
 		return this[INTERNALS$1].counter > 0;
 	}
 
 	get statusText() {
 		return this[INTERNALS$1].statusText;
 	}
 
 	get headers() {
 		return this[INTERNALS$1].headers;
 	}
 
 	/**
   * Clone this response
   *
   * @return  Response
   */
 	clone() {
 		return new Response(clone(this), {
 			url: this.url,
 			status: this.status,
 			statusText: this.statusText,
 			headers: this.headers,
 			ok: this.ok,
 			redirected: this.redirected
 		});
 	}
 }
 
 Body.mixIn(Response.prototype);
 
 Object.defineProperties(Response.prototype, {
 	url: { enumerable: true },
 	status: { enumerable: true },
 	ok: { enumerable: true },
 	redirected: { enumerable: true },
 	statusText: { enumerable: true },
 	headers: { enumerable: true },
 	clone: { enumerable: true }
 });
 
 Object.defineProperty(Response.prototype, Symbol.toStringTag, {
 	value: 'Response',
 	writable: false,
 	enumerable: false,
 	configurable: true
 });
 
 const INTERNALS$2 = Symbol('Request internals');
 
 // fix an issue where "format", "parse" aren't a named export for node <10
 const parse_url = Url.parse;
 const format_url = Url.format;
 
 const streamDestructionSupported = 'destroy' in Stream.Readable.prototype;
 
 /**
  * Check if a value is an instance of Request.
  *
  * @param   Mixed   input
  * @return  Boolean
  */
 function isRequest(input) {
 	return typeof input === 'object' && typeof input[INTERNALS$2] === 'object';
 }
 
 function isAbortSignal(signal) {
 	const proto = signal && typeof signal === 'object' && Object.getPrototypeOf(signal);
 	return !!(proto && proto.constructor.name === 'AbortSignal');
 }
 
 /**
  * Request class
  *
  * @param   Mixed   input  Url or Request instance
  * @param   Object  init   Custom options
  * @return  Void
  */
 class Request {
 	constructor(input) {
 		let init = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};
 
 		let parsedURL;
 
 		// normalize input
 		if (!isRequest(input)) {
 			if (input && input.href) {
 				// in order to support Node.js' Url objects; though WHATWG's URL objects
 				// will fall into this branch also (since their `toString()` will return
 				// `href` property anyway)
 				parsedURL = parse_url(input.href);
 			} else {
 				// coerce input to a string before attempting to parse
 				parsedURL = parse_url(`${input}`);
 			}
 			input = {};
 		} else {
 			parsedURL = parse_url(input.url);
 		}
 
 		let method = init.method || input.method || 'GET';
 		method = method.toUpperCase();
 
 		if ((init.body != null || isRequest(input) && input.body !== null) && (method === 'GET' || method === 'HEAD')) {
 			throw new TypeError('Request with GET/HEAD method cannot have body');
 		}
 
 		let inputBody = init.body != null ? init.body : isRequest(input) && input.body !== null ? clone(input) : null;
 
 		Body.call(this, inputBody, {
 			timeout: init.timeout || input.timeout || 0,
 			size: init.size || input.size || 0
 		});
 
 		const headers = new Headers(init.headers || input.headers || {});
 
 		if (inputBody != null && !headers.has('Content-Type')) {
 			const contentType = extractContentType(inputBody);
 			if (contentType) {
 				headers.append('Content-Type', contentType);
 			}
 		}
 
 		let signal = isRequest(input) ? input.signal : null;
 		if ('signal' in init) signal = init.signal;
 
 		if (signal != null && !isAbortSignal(signal)) {
 			throw new TypeError('Expected signal to be an instanceof AbortSignal');
 		}
 
 		this[INTERNALS$2] = {
 			method,
 			redirect: init.redirect || input.redirect || 'follow',
 			headers,
 			parsedURL,
 			signal
 		};
 
 		// node-fetch-only options
 		this.follow = init.follow !== undefined ? init.follow : input.follow !== undefined ? input.follow : 20;
 		this.compress = init.compress !== undefined ? init.compress : input.compress !== undefined ? input.compress : true;
 		this.counter = init.counter || input.counter || 0;
 		this.agent = init.agent || input.agent;
 	}
 
 	get method() {
 		return this[INTERNALS$2].method;
 	}
 
 	get url() {
 		return format_url(this[INTERNALS$2].parsedURL);
 	}
 
 	get headers() {
 		return this[INTERNALS$2].headers;
 	}
 
 	get redirect() {
 		return this[INTERNALS$2].redirect;
 	}
 
 	get signal() {
 		return this[INTERNALS$2].signal;
 	}
 
 	/**
   * Clone this request
   *
   * @return  Request
   */
 	clone() {
 		return new Request(this);
 	}
 }
 
 Body.mixIn(Request.prototype);
 
 Object.defineProperty(Request.prototype, Symbol.toStringTag, {
 	value: 'Request',
 	writable: false,
 	enumerable: false,
 	configurable: true
 });
 
 Object.defineProperties(Request.prototype, {
 	method: { enumerable: true },
 	url: { enumerable: true },
 	headers: { enumerable: true },
 	redirect: { enumerable: true },
 	clone: { enumerable: true },
 	signal: { enumerable: true }
 });
 
 /**
  * Convert a Request to Node.js http request options.
  *
  * @param   Request  A Request instance
  * @return  Object   The options object to be passed to http.request
  */
 function getNodeRequestOptions(request) {
 	const parsedURL = request[INTERNALS$2].parsedURL;
 	const headers = new Headers(request[INTERNALS$2].headers);
 
 	// fetch step 1.3
 	if (!headers.has('Accept')) {
 		headers.set('Accept', '*/*');
 	}
 
 	// Basic fetch
 	if (!parsedURL.protocol || !parsedURL.hostname) {
 		throw new TypeError('Only absolute URLs are supported');
 	}
 
 	if (!/^https?:$/.test(parsedURL.protocol)) {
 		throw new TypeError('Only HTTP(S) protocols are supported');
 	}
 
 	if (request.signal && request.body instanceof Stream.Readable && !streamDestructionSupported) {
 		throw new Error('Cancellation of streamed requests with AbortSignal is not supported in node < 8');
 	}
 
 	// HTTP-network-or-cache fetch steps 2.4-2.7
 	let contentLengthValue = null;
 	if (request.body == null && /^(POST|PUT)$/i.test(request.method)) {
 		contentLengthValue = '0';
 	}
 	if (request.body != null) {
 		const totalBytes = getTotalBytes(request);
 		if (typeof totalBytes === 'number') {
 			contentLengthValue = String(totalBytes);
 		}
 	}
 	if (contentLengthValue) {
 		headers.set('Content-Length', contentLengthValue);
 	}
 
 	// HTTP-network-or-cache fetch step 2.11
 	if (!headers.has('User-Agent')) {
 		headers.set('User-Agent', 'node-fetch/1.0 (+https://github.com/bitinn/node-fetch)');
 	}
 
 	// HTTP-network-or-cache fetch step 2.15
 	if (request.compress && !headers.has('Accept-Encoding')) {
 		headers.set('Accept-Encoding', 'gzip,deflate');
 	}
 
 	let agent = request.agent;
 	if (typeof agent === 'function') {
 		agent = agent(parsedURL);
 	}
 
 	if (!headers.has('Connection') && !agent) {
 		headers.set('Connection', 'close');
 	}
 
 	// HTTP-network fetch step 4.2
 	// chunked encoding is handled by Node.js
 
 	return Object.assign({}, parsedURL, {
 		method: request.method,
 		headers: exportNodeCompatibleHeaders(headers),
 		agent
 	});
 }
 
 /**
  * abort-error.js
  *
  * AbortError interface for cancelled requests
  */
 
 /**
  * Create AbortError instance
  *
  * @param   String      message      Error message for human
  * @return  AbortError
  */
 function AbortError(message) {
   Error.call(this, message);
 
   this.type = 'aborted';
   this.message = message;
 
   // hide custom error implementation details from end-users
   Error.captureStackTrace(this, this.constructor);
 }
 
 AbortError.prototype = Object.create(Error.prototype);
 AbortError.prototype.constructor = AbortError;
 AbortError.prototype.name = 'AbortError';
 
 // fix an issue where "PassThrough", "resolve" aren't a named export for node <10
 const PassThrough$1 = Stream.PassThrough;
 const resolve_url = Url.resolve;
 
 /**
  * Fetch function
  *
  * @param   Mixed    url   Absolute url or Request instance
  * @param   Object   opts  Fetch options
  * @return  Promise
  */
 function 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;
 
 	// wrap http.request into fetch
 	return new fetch.Promise(function (resolve, reject) {
 		// build request object
 		const request = new Request(url, opts);
 		const options = getNodeRequestOptions(request);
 
 		const send = (options.protocol === 'https:' ? https : http).request;
 		const signal = request.signal;
 
 		let response = null;
 
 		const abort = function abort() {
 			let error = new AbortError('The user aborted a request.');
 			reject(error);
 			if (request.body && request.body instanceof Stream.Readable) {
 				request.body.destroy(error);
 			}
 			if (!response || !response.body) return;
 			response.body.emit('error', error);
 		};
 
 		if (signal && signal.aborted) {
 			abort();
 			return;
 		}
 
 		const abortAndFinalize = function abortAndFinalize() {
 			abort();
 			finalize();
 		};
 
 		// send request
 		const req = send(options);
 		let reqTimeout;
 
 		if (signal) {
 			signal.addEventListener('abort', abortAndFinalize);
 		}
 
 		function finalize() {
 			req.abort();
 			if (signal) signal.removeEventListener('abort', abortAndFinalize);
 			clearTimeout(reqTimeout);
 		}
 
 		if (request.timeout) {
 			req.once('socket', function (socket) {
 				reqTimeout = setTimeout(function () {
 					reject(new FetchError(`network timeout at: ${request.url}`, 'request-timeout'));
 					finalize();
 				}, request.timeout);
 			});
 		}
 
 		req.on('error', function (err) {
 			reject(new FetchError(`request to ${request.url} failed, reason: ${err.message}`, 'system', err));
 			finalize();
 		});
 
 		req.on('response', function (res) {
 			clearTimeout(reqTimeout);
 
 			const headers = createHeadersLenient(res.headers);
 
 			// HTTP fetch step 5
 			if (fetch.isRedirect(res.statusCode)) {
 				// HTTP fetch step 5.2
 				const location = headers.get('Location');
 
 				// HTTP fetch step 5.3
 				const locationURL = location === null ? null : resolve_url(request.url, location);
 
 				// HTTP fetch step 5.5
 				switch (request.redirect) {
 					case 'error':
 						reject(new FetchError(`redirect mode is set to error: ${request.url}`, 'no-redirect'));
 						finalize();
 						return;
 					case 'manual':
 						// node-fetch-specific step: make manual redirect a bit easier to use by setting the Location header value to the resolved URL.
 						if (locationURL !== null) {
 							// handle corrupted header
 							try {
 								headers.set('Location', locationURL);
 							} catch (err) {
 								// istanbul ignore next: nodejs server prevent invalid response headers, we can't test this through normal request
 								reject(err);
 							}
 						}
 						break;
 					case 'follow':
 						// HTTP-redirect fetch step 2
 						if (locationURL === null) {
 							break;
 						}
 
 						// HTTP-redirect fetch step 5
 						if (request.counter >= request.follow) {
 							reject(new FetchError(`maximum redirect reached at: ${request.url}`, 'max-redirect'));
 							finalize();
 							return;
 						}
 
 						// HTTP-redirect fetch step 6 (counter increment)
 						// Create a new Request object.
 						const requestOpts = {
 							headers: new Headers(request.headers),
 							follow: request.follow,
 							counter: request.counter + 1,
 							agent: request.agent,
 							compress: request.compress,
 							method: request.method,
 							body: request.body,
 							signal: request.signal,
 							timeout: request.timeout
 						};
 
 						// HTTP-redirect fetch step 9
 						if (res.statusCode !== 303 && request.body && getTotalBytes(request) === null) {
 							reject(new FetchError('Cannot follow redirect with body being a readable stream', 'unsupported-redirect'));
 							finalize();
 							return;
 						}
 
 						// HTTP-redirect fetch step 11
 						if (res.statusCode === 303 || (res.statusCode === 301 || res.statusCode === 302) && request.method === 'POST') {
 							requestOpts.method = 'GET';
 							requestOpts.body = undefined;
 							requestOpts.headers.delete('content-length');
 						}
 
 						// HTTP-redirect fetch step 15
 						resolve(fetch(new Request(locationURL, requestOpts)));
 						finalize();
 						return;
 				}
 			}
 
 			// prepare response
 			res.once('end', function () {
 				if (signal) signal.removeEventListener('abort', abortAndFinalize);
 			});
 			let body = res.pipe(new PassThrough$1());
 
 			const response_options = {
 				url: request.url,
 				status: res.statusCode,
 				statusText: res.statusMessage,
 				headers: headers,
 				size: request.size,
 				timeout: request.timeout,
 				counter: request.counter
 			};
 
 			// HTTP-network fetch step 12.1.1.3
 			const codings = headers.get('Content-Encoding');
 
 			// HTTP-network fetch step 12.1.1.4: handle content codings
 
 			// 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 (!request.compress || request.method === 'HEAD' || codings === null || res.statusCode === 204 || res.statusCode === 304) {
 				response = new Response(body, response_options);
 				resolve(response);
 				return;
 			}
 
 			// For Node v6+
 			// Be less strict when decoding compressed responses, since sometimes
 			// servers send slightly invalid responses that are still accepted
 			// by common browsers.
 			// Always using Z_SYNC_FLUSH is what cURL does.
 			const zlibOptions = {
 				flush: zlib.Z_SYNC_FLUSH,
 				finishFlush: zlib.Z_SYNC_FLUSH
 			};
 
 			// for gzip
 			if (codings == 'gzip' || codings == 'x-gzip') {
 				body = body.pipe(zlib.createGunzip(zlibOptions));
 				response = new Response(body, response_options);
 				resolve(response);
 				return;
 			}
 
 			// for deflate
 			if (codings == 'deflate' || codings == 'x-deflate') {
 				// handle the infamous raw deflate response from old servers
 				// a hack for old IIS and Apache servers
 				const raw = res.pipe(new PassThrough$1());
 				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());
 					}
 					response = new Response(body, response_options);
 					resolve(response);
 				});
 				return;
 			}
 
 			// for br
 			if (codings == 'br' && typeof zlib.createBrotliDecompress === 'function') {
 				body = body.pipe(zlib.createBrotliDecompress());
 				response = new Response(body, response_options);
 				resolve(response);
 				return;
 			}
 
 			// otherwise, use response as-is
 			response = new Response(body, response_options);
 			resolve(response);
 		});
 
 		writeToStream(req, request);
 	});
 }
 /**
  * Redirect code matching
  *
  * @param   Number   code  Status code
  * @return  Boolean
  */
 fetch.isRedirect = function (code) {
 	return code === 301 || code === 302 || code === 303 || code === 307 || code === 308;
 };
 
 // expose Promise
 fetch.Promise = global.Promise;
 
 export default fetch;
 export { Headers, Request, Response, FetchError };