Utility functions for media types (MIME types).

A transform stream that only transforms from the zero-indexed start and end bytes (both inclusive).

A map of extensions for a given media type.

A record of all the status codes text.

Calculate an ETag for an entity. When the entity is a specific set of data it will be fingerprinted as a "strong" tag, otherwise if it is just file information, it will be calculated as a weak tag.

Decodes a given base64url-encoded string.

Convert data into a base64url-encoded string.

Return the extension of the path with leading period.

A helper function that takes the value from the If-None-Match header and a calculated etag for the target entity and returns false if the etag for the entity matches the supplied value, otherwise true.

Join all given a sequence of paths,then normalizes the resulting path.

Given an extension or media type, return a full Content-Type or Content-Disposition header value.

For a given media type, return the most relevant extension, or undefined if no extension can be found.

Returns the extensions known to be associated with the media type type. The returned extensions will each begin with a leading dot, as in .html.

Serializes the media type and the optional parameters as a media type conforming to RFC 2045 and RFC 2616.

Given a media type or header value, identify the encoding charset. If the charset cannot be determined, the function returns undefined.

Parses the media type and any optional parameters, per RFC 1521. Media types are the values in Content-Type and Content-Disposition headers. On success the function returns a tuple where the first element is the media type and the second element is the optional parameters or undefined if there are none.

Returns the media type associated with the file extension. Values are normalized to lower case and matched irrespective of a leading ..