go-nacelle / pgutil

Nacelle Postgres Utilities

Postgres utilities for use with nacelle.

---

Usage

This library creates a sqlx connection wrapped in a nacelle logger. The supplied initializer adds this connection into the nacelle service container under the key db. The initializer will block until a ping succeeds.

func setup(processes nacelle.ProcessContainer, services nacelle.ServiceContainer) error {
    processes.RegisterInitializer(pgutil.NewInitializer())

    // additional setup
    return nil
}

This library uses golang migrate to optionally run migrations on application startup. To configure migrations, supply a source driver to the initializer, as follows.

import (
    _ "github.com/golang-migrate/migrate/v4/source/file"
    "github.com/golang-migrate/migrate/v4/source"
)

func setup(processes nacelle.ProcessContainer, services nacelle.ServiceContainer) error {
    migrationSourceDriver, err := source.Open("file:///migrations")
	if err != nil {
		return err
	}

    processes.RegisterInitializer(pgutil.NewInitializer(
        pgutil.WithMigrationSourceDriver(migrationSourceDriver)
    ))

    // ...
}

Configuration

The default service behavior can be configured by the following environment variables.

Environment Variable	Required	Default	Description
DATABASE_URL	yes		The connection string of the remote database.
LOG_SQL_QUERIES		false	Whether or not to log parameterized SQL queries.
MIGRATIONS_TABLE		schema_migrations	The name of the migrations table.
MIGRATIONS_SCHEMA_NAME		default	The name of the schema used during migrations.
FAIL_ON_NEWER_MIGRATION_VERSION		false	If true, fail startup when the database migration version is newer than the known set of migrations.