media-type

warning: this was original a fork of mime intending to add some of the parts missing in the mime crate. Since then it largely diverged from the mime crate and is now a re-write/alternative implementation instead of a fork as there is hardly any overlap with the original crate. Sadly it became slightly complex and needs to go through some simplification and optimization before it can be widely used. If possible it will be merged with the mime crate in the future after simplification/optimization. Through for some use cases it's still fine. Just slower then mime and not always very ergonomic.

A crate providing media-type type(s). Media-types are also sometimes known as mime-type or just mime (but the last one is wrong as as media-types are just a small part of the mime standart).

A classical example for a media type is text/plain; charset=utf-8.

While media types seem to be simple they have some tricky parts (around encoding non us-ascii chars and semantic equality) and sadly there is not a media-type standard. Instead they are defined in multiple standards and there definition differs. But not only does the definition differ "thinks" they are used in they also differ depending of different ways the standard can be used. E.g. media-types from the http standard differ in wether or not the "obsolete" part of the http grammar can be used which was often (miss) used to add non us-ascii text (through by now there is a "official" way how to encode non us-ascii utf-8, which is based to a similar standard for media-types in mime/mail but with some differences).

The most strict mime standard is the one used for registering media-types with the IANA registry (which should always be done). While all media-types you create should comply with that standard you likely might have to handle media-types with are either incompatible or do extend the grammer on a non syntactic but semantic level. E.g. by specifying that parameters which have a certain form should be interpreted as percent encoded utf-8.

Alternatively there are some lossy standards about parsing media types in a very fail safe wai but potentially getting out garbage types which can't be used for anything.

The idea behind this crate is to provide a way to:

1. Have some form of "any" media type which can be read but does not specify which grammar was used to parse/validate it.
2. Have a number of wrappers which, in a type-safe way, add information about which grammar was used to validate it and as such give guarantees about it's structure.
3. Be generic enough to allow people to add there own approach.