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A super simple utility library for dealing with mime-types
Pull request Compare This branch is 92 commits behind broofa:master.


Support for mapping between file extensions and MIME types. This module uses the latest version of the Apache "mime.types" file (maps over 620 types to 800+ extensions). It is also trivially easy to add your own types and extensions, should you need to do that.


Install with npm:

npm install mime

API - Queries


Get the mime type associated with a file. This is method is case-insensitive. Everything in path up to and including the last '/' or '.' is ignored, so you can pass it paths, filenames, or extensions, like so:

var mime = require('mime');

mime.lookup('/path/to/file.txt');         // => 'text/plain'
mime.lookup('file.txt');                  // => 'text/plain'
mime.lookup('.txt');                      // => 'text/plain'
mime.lookup('htm');                       // => 'text/html'

mime.extension(type) - lookup the default extension for type

mime.extension('text/html');                 // => 'html'
mime.extension('application/octet-stream');  // => 'bin'

mime.charsets.lookup() - map mime-type to charset

mime.charsets.lookup('text/plain');        // => 'UTF-8'

(The logic for charset lookups is pretty rudimentary. Feel free to suggest improvements.)

API - Customizing

The following APIs allow you to add your own type mappings within your project. If you feel a type should be included as part of node-mime, see requesting new types.

mime.define() - Add custom mime/extension mappings

    'text/x-some-format': ['x-sf', 'x-sft', 'x-sfml'],
    'application/x-my-type': ['x-mt', 'x-mtt'],
    // etc ...

mime.lookup('x-sft');                 // => 'text/x-some-format'
mime.extension('text/x-some-format'); // => 'x-sf'

mime.load(filepath) - Load mappings from an Apache ".types" format file

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