mirror of https://github.com/thangisme/notes.git
37 lines
900 B
JavaScript
37 lines
900 B
JavaScript
var JSONStream = require('JSONStream')
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var combiner = require('stream-combiner')
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var through = require('through2')
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module.exports = function(filter, opts) {
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if (!opts) opts = {}
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var pipeline = [
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JSONStream.parse(filter)
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]
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if (opts.match) {
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pipeline.push(createFunctionStream(opts.match, function(output, object, next) {
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if (!!output) this.push(object)
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next()
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}))
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}
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pipeline.push(JSONStream.stringify('', '\n', ''))
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return combiner.apply(null, pipeline)
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}
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function createFunctionStream(func, customTransform) {
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var funcStr = 'var that = ' + func + ';\n return that;'
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var compiled = new Function(funcStr)
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function transform(obj, enc, next) {
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var out = compiled.call(obj, obj)
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if (customTransform) {
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customTransform.call(this, out, obj, next)
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} else {
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this.push(out)
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next()
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}
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}
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return through.obj(transform)
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} |