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/*!
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* compressible
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* Copyright(c) 2013 Jonathan Ong
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* Copyright(c) 2014 Jeremiah Senkpiel
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* Copyright(c) 2015 Douglas Christopher Wilson
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* MIT Licensed
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*/
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'use strict'
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/**
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* Module dependencies.
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* @private
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*/
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var db = require('mime-db')
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/**
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* Module variables.
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* @private
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*/
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var COMPRESSIBLE_TYPE_REGEXP = /^text\/|\+(?:json|text|xml)$/i
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var EXTRACT_TYPE_REGEXP = /^\s*([^;\s]*)(?:;|\s|$)/
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/**
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* Module exports.
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* @public
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*/
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module.exports = compressible
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/**
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* Checks if a type is compressible.
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*
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* @param {string} type
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* @return {Boolean} compressible
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* @public
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*/
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function compressible (type) {
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if (!type || typeof type !== 'string') {
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return false
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}
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// strip parameters
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var match = EXTRACT_TYPE_REGEXP.exec(type)
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var mime = match && match[1].toLowerCase()
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var data = db[mime]
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// return database information
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if (data && data.compressible !== undefined) {
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return data.compressible
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}
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// fallback to regexp or unknown
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return COMPRESSIBLE_TYPE_REGEXP.test(mime) || undefined
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}
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