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