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