35 lines
854 B
JavaScript
35 lines
854 B
JavaScript
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'use strict';
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module.exports = SliceStream;
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var Transform = require('readable-stream/transform');
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var inherits = require("util").inherits;
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inherits(SliceStream, Transform);
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function SliceStream(opts, sliceFn) {
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if (!(this instanceof SliceStream)) {
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return new SliceStream(opts, sliceFn);
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}
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this._opts = opts;
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this._accumulatedLength = 0;
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this.sliceFn = sliceFn;
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Transform.call(this);
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}
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SliceStream.prototype._transform = function (chunk, encoding, callback) {
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this._accumulatedLength += chunk.length;
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if (this._accumulatedLength >= this._opts.length) {
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//todo handle more than one slice in a stream
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var offset = chunk.length - (this._accumulatedLength - this._opts.length);
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this.sliceFn(chunk.slice(0, offset), true, chunk.slice(offset));
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callback();
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} else {
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this.sliceFn(chunk);
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callback();
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}
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};
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