418 I'm a Teapot

[mnot]

Requests implements the 418 I'm a Teapot status code in status_codes.py.

Its source is RFC2324, Hyper Text Coffee Pot Control Protocol (HTCPCP/1.0). Note the title - HTCPCP/1.0 is not HTTP/1.x.

HTCPCP was an April 1 joke by Larry to illustrate how people were abusing HTTP in various ways. Ironically, it's not being used to abuse HTTP itself -- people are implementing parts of HTCPCP in their HTTP stacks.

In particular, Node's support for the HTCPCP 418 I'm a Teapot status code has been used as an argument in the HTTP Working Group to preclude use of 418 in HTTP for real-world purposes.

While we have a number of spare 4xx HTTP status codes that are unregistered now, the semantics of HTTP are something that (hopefully) are going to last for a long time, so one day we may need this code point.

Please consider removing support for 418 from Requests, since it's not a HTTP status code (even by its own definition). I know it's amusing, I know that a few people have knocked up implementations for fun, but it shouldn't pollute the core protocol; folks can extend Node easily enough if they want to play with non-standard semantics.

Thanks,

/cc @Lukasa

[mnot]

BTW, I'm aware this is a breaking change; deprecating and delaying to the next major release is fine.

[kennethreitz]

Line of code in question: https://github.com/requests/requests/blob/master/requests/status_codes.py#L55

[kennethreitz]

Please note the alternative versions for 200 OK: https://github.com/requests/requests/blob/master/requests/status_codes.py#L13

[mnot]

Huh. The only thing that causes me concern there is the use of unicode and backslashes; requests doesn't emit those, does it?

[kennethreitz]

Nope, this is for reverse lookup only — same with I'm a teapot.

[mnot]

OK, that's good. The problem is that implementation is being used as evidence to preclude actual use of the status code, which is going to eventually be a problem.

[tyteen4a03]

Please see nodejs/node#14644 and golang/go#21326 for discussions regarding similar changes.

[kennethreitz]

I'm okay with removing it, unless we want to add other status codes like 420 and friends.

HTTPbin.org is keeping it though :)

[mnot]

Individual servers, I'm less concerned about :)

[kennethreitz]

Send a PR!

[kennethreitz]

Make it against the 3.0.0 branch though, this will be a breaking change.

[WhataShane]

Hold on! I'm the guy behind http://save418.com (https://github.com/WhataShane/save418). I, like many others, enjoy stumbling upon (almost entirely) innocuous gags like 418. It's the sort of thing that'll put a smile on your face even when you're pressed to meet a project deadline and your boss is yapping at you one office over. It'd be a real shame to see it go.

To quote @romellem from the Go thread, who quite eloquently sums up the argument for 418:

Just to be clear, is your argument that when/if the 400 block runs out, we'll want that one extra code available to stretch out the usefulness of the 400 block just a bit further?

Unless I'm reading it incorrectly, the 400 block of HTTP status codes has more than 50 codes available. With the available "space" of the 400 block at more than 50%, this might be a pre-mature optimization for a problem that may never occur (400 block running out of available codes, that is).

Not trying to sound harsh, but I for one like fun little easter eggs that you find throughout a programming career. To me, it shows that everything that goes on to make a computer actually do work is still made by humans, and keeping small slices of that human element is nice (in my opinion). Your argument is sound and logical, but this requested change ever so slightly lowers the "fun-ness" of Go (and potentially NodeJS) in the spirit of engineering robustness. At the end of the day, I have to say I don't think that tradeoff is worth it.

(I appreciate the history lesson though! I always thought 418 was a part of the HTTP/1.x spec; didn't know about the "HTCPCP/1.0" spec. 🙂)

[kennethreitz]

I agree that it's a fun easter egg.

[kennethreitz]

Requests takes itself seriously, but not too seriously. :)

[kennethreitz]

This might be the line of "too seriously".

[TSavo]

Isn't the obvious answer here to make it part of the spec by starting with a new RFC?

[kennethreitz]

@TSavo Clearly!

[nateprewitt]

While I recognize 418 isn't part of the HTTP status code spec in RFC 7231, it does exist in the wild. Even google has it implemented here. In the unlikely event the IETF decides to implement a real use for 418, we'll have plenty of forewarning to address this. I'm in favor of leaving this as it is unless there's a more compelling reason it needs to be removed.

[geeves]

Give me your keys.

[Lukasa]

Just to be clear, I agree with the rest of the Requests team: we should keep the 418 mapping here. But the reason I agree is purely pragmatic, not because of the fun Easter egg (though it is fun): codes.py is used to build a mapping from reason phrase to code. For this reason it should include any reason phrase that is somewhat likely to appear for a given code. For the moment that is I'm A Teapot. If this changes, we'll add any other phrase the IANA assigns.

@mnot, feel free to use this response as a commitment that says that the IETF/IANA should feel free to re-use 418, and not to block it on our behalf. 😉 I think reason phrases are stupid anyhow.

[daenney]

A request to register 418 has been submitted to IANA, under number 979050.

[Lukasa]

Ok; this is not a discussion forum for the merits of 418. @mnot if you want to follow up on this please drop me an email. For everyone else: we appreciate your input, but I feel pretty good about the decision we've made.