chore: upgrade to rustls 0.20

[satyarohith]

All of the tests pass. Clean up left to do.

Closes #1363

[satyarohith]

@seanmonstar, PR is ready for review. :)

[seanmonstar]

Thank you so much! I glanced through it, and it looks right, though granted I'm not familiar with the exact changes in rustls. Looks like there's some rustfmt changes needed.

[djc]

I haven't yet looked at this in detail but it looks strange to me since currently released versions of hyper-rustls don't actually support rustls 0.20, so I expect there might be something fishy going on here?

[satyarohith]

I haven't yet looked at this in detail but it looks strange to me since currently released versions of hyper-rustls don't actually support rustls 0.20, so I expect there might be something fishy going on here?

Hi @djc :)

It's currently using the code from the PR (rustls/hyper-rustls#156). I guess we would have to wait until it's merged and released.

[djc]

Ah, sorry, I got confused (probably having to do with the git rev being at the end of the Cargo dep and me reviewing this on a mobile device initially). Hopefully we can get a new hyper-rustls out soon.

[g2p]

As a heads-up, you might want to use the new builder interfaces added in the hyper-rustls PR (ClientConfigExt and ConnectorBuilder); they seem to handle all the configuration you are doing manually, and they also allow configuring the connector to be HTTPS-only.
If they don't handle it all, let us know!

[seanmonstar]

Looks like something about pulling in the actual release made it so rustls_pemfile is no longer found?

[djc]

Previously the PEM functionality was part of the rustls crate, so enabling the rustls feature would pull it in. Now it's a separate crate, so the Cargo rustls feature needs to make sure to enable the optional rustls-pemfile dependency.

[BiagioFesta]

As @djc said, we need to enable rustls-pemfile dependency (to decode pem files) when rustls feature is enabled.

Something like:

diff --git a/Cargo.toml b/Cargo.toml
index 9c5a879..ea7c57b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -70,7 +70,7 @@ __tls = []
 
 # Enables common rustls code.
 # Equivalent to rustls-tls-manual-roots but shorter :)
-__rustls = ["hyper-rustls", "tokio-rustls", "rustls", "__tls"]
+__rustls = ["hyper-rustls", "tokio-rustls", "rustls", "__tls", "rustls-pemfile"]
 
 # When enabled, disable using the cached SYS_PROXIES.
 __internal_proxy_sys_no_cache = []

should fix the current CI issue

[seanmonstar]

This was picked up and finished in #1388, thanks!