1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
|
var Readable = require('stream').Readable;
var util = require('util');
function isReadable(stream) {
if (typeof stream.pipe !== 'function') {
return false;
}
if (!stream.readable) {
return false;
}
if (typeof stream._read !== 'function') {
return false;
}
if (!stream._readableState) {
return false;
}
return true;
}
function addStream (streams, stream) {
if (!isReadable(stream)) {
throw new Error('All input streams must be readable');
}
var self = this;
stream._buffer = [];
stream.on('readable', function () {
var chunk = stream.read();
while (chunk) {
if (this === streams[0]) {
self.push(chunk);
} else {
this._buffer.push(chunk);
}
chunk = stream.read();
}
});
stream.on('end', function () {
for (var stream = streams[0];
stream && stream._readableState.ended;
stream = streams[0]) {
while (stream._buffer.length) {
self.push(stream._buffer.shift());
}
streams.shift();
}
if (!streams.length) {
self.push(null);
}
});
stream.on('error', this.emit.bind(this, 'error'));
streams.push(stream);
}
function OrderedStreams (streams, options) {
if (!(this instanceof(OrderedStreams))) {
return new OrderedStreams(streams, options);
}
streams = streams || [];
options = options || {};
options.objectMode = true;
Readable.call(this, options);
if (!Array.isArray(streams)) {
streams = [streams];
}
if (!streams.length) {
return this.push(null); // no streams, close
}
var addStreamBinded = addStream.bind(this, []);
streams.forEach(function (item) {
if (Array.isArray(item)) {
item.forEach(addStreamBinded);
} else {
addStreamBinded(item);
}
});
}
util.inherits(OrderedStreams, Readable);
OrderedStreams.prototype._read = function () {};
module.exports = OrderedStreams;
|
