Implement ALPN support for the Deno adapter.

[1st1]

Depends on edgedb/deno@a95fef9

[1st1]

My test file (t.ts):

import {createClient} from "./edgedb-deno/mod.ts";

async function main() {
  let conn = createClient({
    dsn: "_localdev", tlsSecurity: "insecure",
    //tlsCAFile: '/home/yury/.local/share/edgedb/_localdev/edbtlscert.pem'
  });
  console.log('=1');
  await conn.ensureConnected();
  console.log('=2');

  console.log(await conn.querySingle('select 32323'));
  console.log('=3');
}

main()

I was running it with

yarn compileForDeno && \
   ../../deno/target/debug/deno run --allow-all --unstable \
       --unsafely-ignore-certificate-errors t.ts

Assuming that Deno was cloned into the ../../deno directory from the https://github.com/edgedb/deno/tree/alpn branch.

To build Deno locally I followed https://deno.land/manual@v1.16.1/contributing/building_from_source. It's basically just cloning the repo with all submodules and running cargo build.

[1st1]

@jaclarke James, please take a look at this. Specifically check if we need any more APIs for a complete edgedb-deno client. The adapter.deno.ts / tls.connect() function needs some work to pass all connection options. Then try testing without --unsafely-ignore-certificate-errors.

Lastly, by default Deno tries to connect to ::1 at least on my machine, but edgedb-server only listens on 127.0.0.1 (and doesn't listen on IPv6). Passing 127.0.0.1 to deno explicitly doesn't work for some reason (a limitation of rustls? I didn't spend much time debugging that). Assuming that I'll merge edgedb/edgedb#3187 tonight, run edb server -I "::1" to allow Deno to be able to connect using TLS.

[jaclarke]

Specifically check if we need any more APIs for a complete edgedb-deno client.

The client will mostly work without these, but to fully match the behaviour of edgedb-js it looks like we will need a few more:

• To support tlsSecurity values insecure and no_host_verification we need equivalents of the rejectUnauthorized and checkServerIdentity options
• ref/unref for allowing deno to exit while idle connections are open

[jaclarke]

by default Deno tries to connect to ::1 at least on my machine

For me I'm assuming localhost still resolves to 127.0.0.1, since it works without edb server -I "::1", so I guess this depends on the user's system.

[1st1]

we need equivalents of the rejectUnauthorized

Looks like that won't happen: denoland/deno#1371

[1st1]

I've filed a PR to add ALPN support: denoland/deno#12786