/*!
* mime-types
* Copyright(c) 2014 Jonathan Ong
* Copyright(c) 2015 Douglas Christopher Wilson
* MIT Licensed
*/
'use strict'
/**
* Module dependencies.
* @private
*/
var db = require('mime-db')
var extname = require('path').extname
/**
* Module variables.
* @private
*/
var EXTRACT_TYPE_REGEXP = /^\s*([^;\s]*)(?:;|\s|$)/
var TEXT_TYPE_REGEXP = /^text\//i
/**
* Module exports.
* @public
*/
exports.charset = charset
exports.charsets = { lookup: charset }
exports.contentType = contentType
exports.extension = extension
exports.extensions = Object.create(null)
exports.lookup = lookup
exports.types = Object.create(null)
// Populate the extensions/types maps
populateMaps(exports.extensions, exports.types)
/**
* Get the default charset for a MIME type.
*
* @param {string} type
* @return {boolean|string}
*/
function charset (type) {
if (!type || typeof type !== 'string') {
return false
}
// TODO: use media-typer
var match = EXTRACT_TYPE_REGEXP.exec(type)
var mime = match && db[match[1].toLowerCase()]
if (mime && mime.charset) {
return mime.charset
}
// default text/* to utf-8
if (match && TEXT_TYPE_REGEXP.test(match[1])) {
return 'UTF-8'
}
return false
}
/**
* Create a full Content-Type header given a MIME type or extension.
*
* @param {string} str
* @return {boolean|string}
*/
function contentType (str) {
// TODO: should this even be in this module?
if (!str || typeof str !== 'string') {
return false
}
var mime = str.indexOf('/') === -1
? exports.lookup(str)
: str
if (!mime) {
return false
}
// TODO: use content-type or other module
if (mime.indexOf('charset') === -1) {
var charset = exports.charset(mime)
if (charset) mime += '; charset=' + charset.toLowerCase()
}
return mime
}
/**
* Get the default extension for a MIME type.
*
* @param {string} type
* @return {boolean|string}
*/
function extension (type) {
if (!type || typeof type !== 'string') {
return false
}
// TODO: use media-typer
var match = EXTRACT_TYPE_REGEXP.exec(type)
// get extensions
var exts = match && exports.extensions[match[1].toLowerCase()]
if (!exts || !exts.length) {
return false
}
return exts[0]
}
/**
* Lookup the MIME type for a file path/extension.
*
* @param {string} path
* @return {boolean|string}
*/
function lookup (path) {
if (!path || typeof path !== 'string') {
return false
}
// get the extension ("ext" or ".ext" or full path)
var extension = extname('x.' + path)
.toLowerCase()
.substr(1)
if (!extension) {
return false
}
return exports.types[extension] || false
}
/**
* Populate the extensions and types maps.
* @private
*/
function populateMaps (extensions, types) {
// source preference (least -> most)
var preference = ['nginx', 'apache', undefined, 'iana']
Object.keys(db).forEach(function forEachMimeType (type) {
var mime = db[type]
var exts = mime.extensions
if (!exts || !exts.length) {
return
}
// mime -> extensions
extensions[type] = exts
// extension -> mime
for (var i = 0; i < exts.length; i++) {
var extension = exts[i]
if (types[extension]) {
var from = preference.indexOf(db[types[extension]].source)
var to = preference.indexOf(mime.source)
if (types[extension] !== 'application/octet-stream' &&
(from > to || (from === to && types[extension].substr(0, 12) === 'application/'))) {
// skip the remapping
continue
}
}
// set the extension -> mime
types[extension] = type
}
})
}