conncheck - Go linter for db configuration

Installing

go install github.com/dozyio/conncheck/cmd/conncheck@latest

Running

conncheck ./...

Options

-minsec The minimum seconds for SetConnMaxLifetime (default 60). This is a best effort static check but can be unreliable as the value is often set at runtime.

-packages A comma-separated list of packages to trigger linting (default database/sql,gorm.io/gorm,github.com/jmoiron/sqlx)

-timeunits A comma-separated list of time units to validate against (default Second,Minute,Hour)

-printast Print the AST, useful for debugging

Linting

Currently the linter only checks db.SetConnMaxLifetime.

db.SetConnMaxLifetime()

Checks that db.SetConnMaxLifetime is set to a reasonable value to optimise performance. SetConnMaxLifetime accepts a time.Duration that is in nanoseconds but is often configured incorrectly. This can lead to performance issues such as a new connection on every request. In production, we saw a 5x increase in throughput when db.SetConnMaxLifetime was configured correctly.

Recommendations

• When reading the value for SetConnMaxLifetime from a configuration file, use time.ParseDuration() to ensure a time unit is set.