Postgres native tls does not support client certificates.

[linuxuser586]

I'm using v0.5.1 of sqlx and it does not work with native TLS due to missing implementation for including client certificates. I have a working implementation in my fork located at https://github.com/linuxuser586/sqlx/tree/postgres-native-tls-fixes. It is currently based on v0.5.1. I'll create a pull request when it is more stable, has tests, and is based on master.

[abonander]

Blocked on: sfackler/rust-native-tls#209

[abonander]

For RusTLS, the solution in #1166 was acceptable, but it was closed because the author didn't have the time to address the review comments. If someone wants to take that PR, trim it down to just the RusTLS changes and address the nits, we'd gladly merge it.

[smeagolqlo]

Enabling feature flag "tls-rustls" for sqlx, worked for me thanks