Make types.json loading optional?

[Hypercubed]

I am using this module in a web application installed and bundled using JSPM. It works fine from what I can tell. However, I am actually only using a subset of the mime types. I can use mime.define but because mime.js requires types.json the entire file is bundled anyway when I build the application. This is probably not an issue since types.json is fairly small but for an optimal web app I see three options:

1. Fork this module to be API only, doesn't load types.json at all, use mime.define in my app.
2. Fork this module to create a smaller custom types.json file.
3. Somehow modify this module to load types.json only when needed.

Thoughts?

[Hypercubed]

Hello again. I would really like to use this library without loading the default database. Here is what I came up with: https://github.com/Hypercubed/node-mime .

With this fork I can do:

var MimeLookup = require('mime');
var mime = new MimeLookup(require('mime-db'));

The API is not not compatible and should likely be a separate npm module. I'd like to suggest that you or I publish a separate module (published to npm as mime-lookup) that your module (mime) requires. Then your mime.js can be simply:

var MimeLookup = require('mime-lookup');

// Default instance
var mime = new MimeLookup(require('./types.json'));

// Default type
mime.default_type = mime.lookup('bin');

//
// Additional API specific to the default instance
//

mime.Mime = MimeLookup;

/**
 * Lookup a charset based on mime type.
 */
mime.charsets = {
  lookup: function(mimeType, fallback) {
    // Assume text types are utf8
    return (/^text\//).test(mimeType) ? 'UTF-8' : fallback;
  }
};

module.exports = mime;

I'm willing to do this through PRs.

[broofa]

Moving to #161