Javascript/ECMAScript library for parsing Content-Type and Media/MIME type strings
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Content-Type parsing

new MediaType(type, [parameters])

The MediaType represents a parsed Media Type. For use in HTTP, the first (but only the first) q parameter will be parsed as a float. Other parameters are available through the params object. The first argument is the full media type, the second argument, if provided, is strictly a list of parameters.

The toString method converts the object back into a Media type.

var p = new MediaType('text/html;level=1;q=0.5');
p.q === 0.5;
p.params.level === "1"

var q = new MediaType('application/json', {profile: ''});
q.type === "application/json";
q.params.profile === "";

q.q = 1;
q.toString() === 'application/json;q=1;profile=""';


Returns a new instance of MediaType.

splitQuotedString(str, delimiter, quote)

Splits a string by a delimiter character (default: semicolon), ignoring quoted sections (default: double quote).


Splits an Accept (or similar) header into an Array of strings of content-types.

splitContentType('application/json, text/html').map(parseMedia)

select(reps, accept)

Pick an ideal representation to send, given an Array of representations to choose from, and the client-preferred list as an Array.

See example.js for an example.

mediaCmp(a, b)

Accepts two MediaType instances and tests them for being a subset/superset.

If a is a superset of b (b is smaller than a), return 1. If b is a superset of a, return -1. If they are the exact same, return 0. If they are disjoint, return null.

The q-value, if any, is ignored.

mediaCmp(parseMedia('text/html'), parseMedia('text/html')) === 0
mediaCmp(parseMedia('*/*'), parseMedia('text/html')) === 1
mediaCmp(parseMedia('text/html;level=1'), parseMedia('text/html')) === -1
mediaCmp(parseMedia('application/json;profile="v1.json"'), parseMedia('application/json;profile="v2.json"')) === null