Ported Cookies implementation from archive-split

[nhellwig]

This is a port of the cookies implementation from the time when the tide was split into multiple crates.
Changes are:

• ContextExt into RequestExt
• StringError was needed again
• appendHeader also needed

Tests have been ported as well. I was unsure how the strategy will be regarding Error handling so feel free to comment and suggest alternatives. So far I have tried to stay as close to the original version.

Cheers,
Niko

[nhellwig]

Thanks for the comments. Have some time probably next week and will work on it.

[yoshuawuyts]

Something else I'm wondering about now is whether we could make it so parsing the incoming request cookies into the CookieJar could be done on the first call to cookie/set_cookie/remove_cookie. That way APIs that don't use cookies at all wouldn't ever pay the parsing cost, and it would be effectively be zero-cost.

[yoshuawuyts]

@nhellwig phew, that was a large review. I hadn't thought too much about cookie handling until now, but I feel we're really on track for something good here! The comments so far are part architectural, and part implementation specific. Perhaps best would be to start with the architectural ones:

• move set/get methods to Response
• enable the cookie middleware by default
• parse cookies on first access

When put together I'm unsure how well these ideas go. But I think they're the right direction for these APIs. The other comments are mostly implementation-specific.

Thanks so much for putting the work in! I'm very excited about the direction this is headed!

[yoshuawuyts]

@nhellwig ohh, yeah this is getting pretty close now!

The biggest thing that still seems to be missing is enabling the middleware by default. That would allow us to get rid of the Result from all cookie methods as well (replacing it with unwrap instead), which would help simplify the API even further!

[nhellwig]

Yeah that is worth looking at ^^.

Just moved the set_cookie and remove_cookie to Response.
Next I will add doc tests as well.

[yoshuawuyts]

One final small set of changes, and I think we should be good to merge!

[yoshuawuyts]

Yessss, I think we're good to merge now. This is great; thanks @nhellwig!