Files
synapse/rust
Erik JohnstonandClaude Opus 4.8 3c469b3409 Use libpq's default host when the DSN omits one
`tokio_postgres` and libpq disagree on the default host when a DSN gives
no `host=`: tokio-postgres falls back to localhost, whereas libpq (which
`psql` and the rest of Synapse use) applies its configurable compiled-in
default — typically the Unix socket directory — and honours `PGHOST`.

To keep Synapse's existing connection behaviour, `connect()` now runs the
DSN through `fixup_default_host`: if the parsed config has neither a host
nor a hostaddr, it asks libpq what its default would be (via
`PQconnectStart` on an empty conninfo, which applies libpq's defaults/env
without opening a socket) and sets that on the tokio-postgres config.

The libpq call lives in a small hand-written safe wrapper
(`database::postgres::libpq`) over the `pq-sys` crate. pq-sys ships
pre-generated bindings and links the system libpq itself, so — unlike a
bindgen-based binding crate — this needs no libclang to build. The
behaviour is exercised by the Python integration tests.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-11 09:04:57 +00:00
..