Wire Protocol Server for PGlite

A spare-time attempt to understand Postgres Wire Protocol and expose a TCP server, that can be used to redirect all client requests to PGlite instance.

This can be used to connect to a running instance via pgsql or in the future, run a https://postgrest.org/ on top of said PGlite instance and automatically create a temporary, in-memory API endpoints.

It intercepts SSLRequest and StartupMessage messages to fake authentication flow and redirects all remaining packets directly to PGlite instance.

Usage

This repo uses https://bun.sh/ because I don't want to spend time fighting with Node and TypeScript tooling.

Make sure that it's available before running the server, or write your own ts-loader config, ts-node, or whatever people use these days.

bun install
bun start

import { PGlite } from "@electric-sql/pglite";
import { createServer } from "./server.ts";

const db = new PGlite();

await db.exec(`
  create table if not exists test (id serial primary key, name text);
  insert into test (name) values ('foo'), ('bar'), ('baz');
`);

const PORT = 5432;
const pgServer = createServer(db);

pgServer.listen(PORT, () => {
  console.log(`Server bound to port ${PORT}`);
});

$ psql -h localhost -p 5432 -U postgres
postgres=> select * from test;
postgres=> \q

or without db.exec used above

$ psql -h localhost -p 5432 -U postgres
postgres=> create table if not exists test (id serial primary key, name text);
postgres=> insert into test (name) values ('foo'), ('bar'), ('baz');
postgres=> select * from test;
postgres=> \q

Developing

bun watch

Debugging

Debugging network traffic with tshark - https://zignar.net/2022/09/24/using-tshark-to-monitor-pg-traffic/

brew install wireshark

tshark -i lo -f 'tcp port 5432' -d tcp.port==5432,pgsql -T fields -e pgsql.length -e pgsql.type -e pgsql.query

jgoux/pglite-server

Wire Protocol Server for PGlite

Usage

Developing

Debugging