| // Ported from https://github.com/mafintosh/pump with |
| // permission from the author, Mathias Buus (@mafintosh). |
| 'use strict'; |
| |
| var eos; |
| |
| function once(callback) { |
| var called = false; |
| return function () { |
| if (called) return; |
| called = true; |
| callback.apply(void 0, arguments); |
| }; |
| } |
| |
| var _require$codes = require('../../../errors').codes, |
| ERR_MISSING_ARGS = _require$codes.ERR_MISSING_ARGS, |
| ERR_STREAM_DESTROYED = _require$codes.ERR_STREAM_DESTROYED; |
| |
| function noop(err) { |
| // Rethrow the error if it exists to avoid swallowing it |
| if (err) throw err; |
| } |
| |
| function isRequest(stream) { |
| return stream.setHeader && typeof stream.abort === 'function'; |
| } |
| |
| function destroyer(stream, reading, writing, callback) { |
| callback = once(callback); |
| var closed = false; |
| stream.on('close', function () { |
| closed = true; |
| }); |
| if (eos === undefined) eos = require('./end-of-stream'); |
| eos(stream, { |
| readable: reading, |
| writable: writing |
| }, function (err) { |
| if (err) return callback(err); |
| closed = true; |
| callback(); |
| }); |
| var destroyed = false; |
| return function (err) { |
| if (closed) return; |
| if (destroyed) return; |
| destroyed = true; // request.destroy just do .end - .abort is what we want |
| |
| if (isRequest(stream)) return stream.abort(); |
| if (typeof stream.destroy === 'function') return stream.destroy(); |
| callback(err || new ERR_STREAM_DESTROYED('pipe')); |
| }; |
| } |
| |
| function call(fn) { |
| fn(); |
| } |
| |
| function pipe(from, to) { |
| return from.pipe(to); |
| } |
| |
| function popCallback(streams) { |
| if (!streams.length) return noop; |
| if (typeof streams[streams.length - 1] !== 'function') return noop; |
| return streams.pop(); |
| } |
| |
| function pipeline() { |
| for (var _len = arguments.length, streams = new Array(_len), _key = 0; _key < _len; _key++) { |
| streams[_key] = arguments[_key]; |
| } |
| |
| var callback = popCallback(streams); |
| if (Array.isArray(streams[0])) streams = streams[0]; |
| |
| if (streams.length < 2) { |
| throw new ERR_MISSING_ARGS('streams'); |
| } |
| |
| var error; |
| var destroys = streams.map(function (stream, i) { |
| var reading = i < streams.length - 1; |
| var writing = i > 0; |
| return destroyer(stream, reading, writing, function (err) { |
| if (!error) error = err; |
| if (err) destroys.forEach(call); |
| if (reading) return; |
| destroys.forEach(call); |
| callback(error); |
| }); |
| }); |
| return streams.reduce(pipe); |
| } |
| |
| module.exports = pipeline; |