var path = require('path');
var fs = require('fs');
function Mime() {
// Map of extension -> mime type
this.types = Object.create(null);
// Map of mime type -> extension
this.extensions = Object.create(null);
}
/**
* Define mimetype -> extension mappings. Each key is a mime-type that maps
* to an array of extensions associated with the type. The first extension is
* used as the default extension for the type.
*
* e.g. mime.define({'audio/ogg', ['oga', 'ogg', 'spx']});
*
* @param map (Object) type definitions
*/
Mime.prototype.define = function (map) {
for (var type in map) {
var exts = map[type];
for (var i = 0; i < exts.length; i++) {
if (process.env.DEBUG_MIME && this.types[exts[i]]) {
console.warn((this._loading || "define()").replace(/.*\//, ''), 'changes "' + exts[i] + '" extension type from ' +
this.types[exts[i]] + ' to ' + type);
}
this.types[exts[i]] = type;
}
// Default extension is the first one we encounter
if (!this.extensions[type]) {
this.extensions[type] = exts[0];
}
}
};
/**
* Load an Apache2-style ".types" file
*
* This may be called multiple times (it's expected). Where files declare
* overlapping types/extensions, the last file wins.
*
* @param file (String) path of file to load.
*/
Mime.prototype.load = function(file) {
this._loading = file;
// Read file and split into lines
var map = {},
content = fs.readFileSync(file, 'ascii'),
lines = content.split(/[ ]+/);
lines.forEach(function(line) {
// Clean up whitespace/comments, and split into fields
var fields = line.replace(/\s*#.*|^\s*|\s*$/g, '').split(/\s+/);
map[fields.shift()] = fields;
});
this.define(map);
this._loading = null;
};
/**
* Lookup a mime type based on extension
*/
Mime.prototype.lookup = function(path, fallback) {
var ext = path.replace(/^.*[\.\/\\]/, '').toLowerCase();
return this.types[ext] || fallback || this.default_type;
};
/**
* Return file extension associated with a mime type
*/
Mime.prototype.extension = function(mimeType) {
var type = mimeType.match(/^\s*([^;\s]*)(?:;|\s|$)/)[1].toLowerCase();
return this.extensions[type];
};
// Default instance
var mime = new Mime();
// Define built-in types
mime.define(require('./types.json'));
// Default type
mime.default_type = mime.lookup('bin');
//
// Additional API specific to the default instance
//
mime.Mime = Mime;
/**
* Lookup a charset based on mime type.
*/
mime.charsets = {
lookup: function(mimeType, fallback) {
// Assume text types are utf8
return (/^text\/|^application\/(javascript|json)/).test(mimeType) ? 'UTF-8' : fallback;
}
};
module.exports = mime;