hex_api: transition away from http_uri

[michaelklishin]

which has been deprecated in OTP 23 [master].

See erlang/rebar32195 and erlang/rebar3#2191 for the background.

I would be happy to move the to_list/1 function to a utility module but there doesn't seem to be one at the moment. Rebar3 already has one, so I'm not sure if it's worth introducing a new module here.

[michaelklishin]

Worth mentioning that this assumes that we have to support OTP versions < 21 because, well, Rebar3 still supports OTP 18.

If that's not the case this code can be simplified.

[michaelklishin]

Any feedback on this?

[starbelly]

Not a hex team member, but I can say it should support all the way back to 18. If it does not then we have to do hacks in rebar3.

[wojtekmach]

I'll review this more closely this week but I think this is the way to go, thank you for the PR. And yes, we need to support old OTP versions, down to OTP 17 in fact.

[michaelklishin]

Just curious, why is the obligation for support of those four-and five-year-old Erlang versions? The OTP team doesn't update even OTP 19 any more. Is there a support policy that demonstrates when support for Erlang < 21 will be dropped?

[wojtekmach]

hex_core is used in hex and hex is compatible with elixir 1.x, 1.0 requires otp 17. There will definitely be future releases of hex and hex_core that will drop compatibility with old versions but nothing set in stone yet.

[michaelklishin]

Any feedback on this? Warnings in Rebar currently make it impossible to build it on OTP 23. We have a Rebar PR ready and waiting for this module to be upstreamed.

[wojtekmach]

@michaelklishin LGTM. I made very minor changes, just moving some code around to keep the old supporting more tied together, let me know what you think. And sorry for the delay.

[michaelklishin]

@wojtekmach sure, LGTM. Thanks.