go-service
🐘 SQL (Postgres)
SQL root config is database/sql.Config, with Postgres under sql.pg.
Postgres config embeds common pool + DSN config (database/sql/config.Config), including writer/reader pools. Each role pool owns its dsns and settings. Enabled SQL pool settings must set positive max_open_conns and max_idle_conns; max_idle_conns must not exceed max_open_conns.
module.Server and module.Client both include sql.Module, which currently wires PostgreSQL support via database/sql/pg.Module.
Enablement is presence-based: a nil sql block or a nil sql.pg block disables SQL wiring. When enabled, the pgx stdlib driver is registered under the name pg, and reader/writer DSNs are resolved using the source-string rules described in Source strings. Enabled PostgreSQL config must provide at least one non-empty reader.dsns[].url or writer.dsns[].url. Driver instrumentation is installed when tracing or metrics are enabled, OpenTelemetry database/sql stats metrics are registered when metrics are enabled, and the resulting pools are closed on lifecycle stop.
SQL wiring creates database/sql pool handles and applies pool settings, but it
does not ping PostgreSQL during construction. Call DBs.Ping, DBs.PingWriter,
or DBs.PingReader with an SLO-appropriate
deadline, or register health/checker.NewDBChecker, when startup or readiness
should verify database reachability.
Example (with source strings for DSNs):
sql:
pg:
reader:
dsns:
- url: env:PG_READER_DSN
settings:
max_open_conns: 20
max_idle_conns: 10
conn_max_idle_time: 30m
conn_max_lifetime: 1h
writer:
dsns:
- url: env:PG_WRITER_DSN
settings:
max_open_conns: 3
max_idle_conns: 2
conn_max_idle_time: 10m
conn_max_lifetime: 30m
Example (literal DSN; not recommended for production secrets):
sql:
pg:
writer:
dsns:
- url: postgres://user:pass@localhost:5432/dbname?sslmode=disable
settings:
max_open_conns: 10
max_idle_conns: 5
Dependencies
