1 | var streamify = require('./streamify.js')
|
---|
2 | , defer = require('./defer.js')
|
---|
3 | ;
|
---|
4 |
|
---|
5 | // API
|
---|
6 | module.exports = ReadableAsyncKit;
|
---|
7 |
|
---|
8 | /**
|
---|
9 | * Base constructor for all streams
|
---|
10 | * used to hold properties/methods
|
---|
11 | */
|
---|
12 | function ReadableAsyncKit()
|
---|
13 | {
|
---|
14 | ReadableAsyncKit.super_.apply(this, arguments);
|
---|
15 |
|
---|
16 | // list of active jobs
|
---|
17 | this.jobs = {};
|
---|
18 |
|
---|
19 | // add stream methods
|
---|
20 | this.destroy = destroy;
|
---|
21 | this._start = _start;
|
---|
22 | this._read = _read;
|
---|
23 | }
|
---|
24 |
|
---|
25 | /**
|
---|
26 | * Destroys readable stream,
|
---|
27 | * by aborting outstanding jobs
|
---|
28 | *
|
---|
29 | * @returns {void}
|
---|
30 | */
|
---|
31 | function destroy()
|
---|
32 | {
|
---|
33 | if (this.destroyed)
|
---|
34 | {
|
---|
35 | return;
|
---|
36 | }
|
---|
37 |
|
---|
38 | this.destroyed = true;
|
---|
39 |
|
---|
40 | if (typeof this.terminator == 'function')
|
---|
41 | {
|
---|
42 | this.terminator();
|
---|
43 | }
|
---|
44 | }
|
---|
45 |
|
---|
46 | /**
|
---|
47 | * Starts provided jobs in async manner
|
---|
48 | *
|
---|
49 | * @private
|
---|
50 | */
|
---|
51 | function _start()
|
---|
52 | {
|
---|
53 | // first argument – runner function
|
---|
54 | var runner = arguments[0]
|
---|
55 | // take away first argument
|
---|
56 | , args = Array.prototype.slice.call(arguments, 1)
|
---|
57 | // second argument - input data
|
---|
58 | , input = args[0]
|
---|
59 | // last argument - result callback
|
---|
60 | , endCb = streamify.callback.call(this, args[args.length - 1])
|
---|
61 | ;
|
---|
62 |
|
---|
63 | args[args.length - 1] = endCb;
|
---|
64 | // third argument - iterator
|
---|
65 | args[1] = streamify.iterator.call(this, args[1]);
|
---|
66 |
|
---|
67 | // allow time for proper setup
|
---|
68 | defer(function()
|
---|
69 | {
|
---|
70 | if (!this.destroyed)
|
---|
71 | {
|
---|
72 | this.terminator = runner.apply(null, args);
|
---|
73 | }
|
---|
74 | else
|
---|
75 | {
|
---|
76 | endCb(null, Array.isArray(input) ? [] : {});
|
---|
77 | }
|
---|
78 | }.bind(this));
|
---|
79 | }
|
---|
80 |
|
---|
81 |
|
---|
82 | /**
|
---|
83 | * Implement _read to comply with Readable streams
|
---|
84 | * Doesn't really make sense for flowing object mode
|
---|
85 | *
|
---|
86 | * @private
|
---|
87 | */
|
---|
88 | function _read()
|
---|
89 | {
|
---|
90 |
|
---|
91 | }
|
---|