Motivation
@mlusetti reported on X (2026-03-22) that rpg gives connection failed: db error where psql connects fine. The error message issue is fixed in #708, but the underlying connection compatibility needs a full audit.
All connection paths to test
A. TCP connections
| # |
Method |
Example |
Expected |
| A1 |
Basic TCP |
rpg -h localhost -p 5432 -U postgres |
✅/❌ |
| A2 |
TCP with password |
rpg -h host -p 5432 -U user -W |
✅/❌ |
| A3 |
TCP with PGPASSWORD |
PGPASSWORD=x rpg -h host -U user |
✅/❌ |
| A4 |
TCP with .pgpass |
~/.pgpass file, no password prompt |
✅/❌ |
| A5 |
TCP no port (default 5432) |
rpg -h localhost -U postgres |
✅/❌ |
| A6 |
TCP with database |
rpg -h localhost -U u -d mydb |
✅/❌ |
B. Unix socket connections
| # |
Method |
Example |
Expected |
| B1 |
Default socket |
rpg -U postgres (no -h) |
✅/❌ |
| B2 |
Explicit socket path |
rpg -h /var/run/postgresql -U postgres |
✅/❌ |
| B3 |
Socket with port suffix |
rpg -h /var/run/postgresql -p 5432 -U postgres |
✅/❌ |
| B4 |
PGHOST as socket dir |
PGHOST=/tmp rpg -U postgres |
✅/❌ |
C. URI / connection string
| # |
Method |
Example |
Expected |
| C1 |
postgres:// URI |
rpg postgres://user:pass@host/db |
✅/❌ |
| C2 |
postgres:// no password |
rpg postgres://user@host/db |
✅/❌ |
| C3 |
postgresql:// scheme |
rpg postgresql://user@host/db |
✅/❌ |
| C4 |
URI with sslmode |
rpg postgres://user@host/db?sslmode=require |
✅/❌ |
| C5 |
URI with socket |
rpg postgres:///db?host=/var/run/postgresql |
✅/❌ |
| C6 |
key=value connstring |
rpg "host=localhost user=u dbname=d" |
✅/❌ |
D. SSL modes
| # |
sslmode |
Expected |
| D1 |
disable |
✅/❌ |
| D2 |
prefer (default) |
✅/❌ |
| D3 |
require |
✅/❌ |
| D4 |
verify-ca |
✅/❌ |
| D5 |
verify-full |
✅/❌ |
E. Environment variables
| # |
Var |
Expected |
| E1 |
PGHOST |
✅/❌ |
| E2 |
PGPORT |
✅/❌ |
| E3 |
PGUSER |
✅/❌ |
| E4 |
PGPASSWORD |
✅/❌ |
| E5 |
PGDATABASE |
✅/❌ |
| E6 |
PGPASSFILE |
✅/❌ |
| E7 |
PGSERVICE / pg_service.conf |
✅/❌ |
| E8 |
PGSSLMODE |
✅/❌ |
| E9 |
PGCONNECT_TIMEOUT |
✅/❌ |
| E10 |
PGAPPNAME |
✅/❌ |
F. Edge cases
| # |
Case |
Expected |
| F1 |
Wrong password → clear error |
✅/❌ |
| F2 |
Wrong host → clear error (not 'db error') |
✅/❌ |
| F3 |
Connection refused → clear error |
✅/❌ |
| F4 |
Timeout → clear error with timeout value |
✅/❌ |
| F5 |
Multiple hosts (failover) |
✅/❌ |
| F6 |
target_session_attrs=read-write |
✅/❌ |
| F7 |
-c flag with connection |
✅/❌ |
| F8 |
Multiple -c flags |
✅/❌ |
| F9 |
-f flag (file input) |
✅/❌ |
G. Auth methods
| # |
Method |
Expected |
| G1 |
trust |
✅/❌ |
| G2 |
md5 |
✅/❌ |
| G3 |
scram-sha-256 |
✅/❌ |
| G4 |
peer (unix socket) |
✅/❌ |
Test environment
Local Docker PGs available:
- PG17:
localhost:5433 (trust auth, user=postgres)
- PG18:
localhost:5435 (trust auth, user=postgres)
- PG13:
localhost:5434 (trust auth, user=postgres)
Definition of done
All ✅ or filed as separate bugs with reproduction steps.
