Add `supabase db shell` command to inspect databases

[daniel-j-h]

When working on the database, every now and then having a psql shell is crucial e.g. for debugging, for inspecting, and so on.

At the moment there are ways to get such a psql shell in the local database with

docker exec -it supabase_db_portal psql -U postgres

and in the remote database with a bit more magic e.g. what I'm using

#!/usr/bin/env bash

set -o errexit
set -o pipefail
set -o nounset

if [ $# -lt 2 ]; then
    echo "Usage: $(basename $0) db-cert-path project-ref"
    echo
    echo "You can download the ssl certificate in the supabase dashboard under Project Settings > Configuration > Database"
    exit 1
fi

readonly DBCERT="$1"
readonly PROJECT="$2"

echo "You will have to enter the supabase project's database password you provided when you created the project"

docker run -it --rm --init -v "$DBCERT:/opt/supabase.crt:ro" postgres:15-bookworm \
  psql "sslmode=verify-full sslrootcert=/opt/supabase.crt host=aws-0-eu-central-1.pooler.supabase.com dbname=postgres user=postgres.${PROJECT}"

It would be great to have a command like supabase db shell (or similar) that drops us into a psql shell in a postgres container with the matching postgres database version (similar to the workaround above). For both local and remote databases.