What is the most appropriate media type (formally MIME type) to use when sending data structured with YAML over HTTP and why?
There is no registered application type or text type that I can see.
Example:
> GET /example.yaml
< Content-Type: ????
<
< --- # Favorite movies
< - Casablanca
< - North by Northwest
< - Notorious
Possible options:
Ruby on Rails uses application/x-yaml with an alternative of text/yaml (source).
I think it's just a matter of convention, there is no technical why, as far as I can tell.
I'd say text/x-yaml:
text over application because it's a human-readable
x-yaml over yaml because it hasn't been accepted into the registered list of mime types.
Edit: from RFC 3023 (XML Media Types):
The top-level media type "text" has some restrictions on MIME entities and they are described in [RFC2045] and [RFC2046]. In particular, the UTF-16 family, UCS-4, and UTF-32 are not allowed (except over HTTP[RFC2616], which uses a MIME-like mechanism).
Interesting... Not exactly sure what it means, but food for thought.
The IETF is working to register the application/yaml media type and the +yaml structured syntax suffix.
Currently, we are not registering text/yaml. https://github.com/ietf-wg-httpapi/mediatypes/blob/main/draft-ietf-httpapi-yaml-mediatypes.md
Feel free to participate in the discussion.