migrate

Migrate Command Line Tool

Migrate is the command-line tool supporting the https://github.com/sbowman/migrations package. It provides both a usable tool to run database migrations without embedding the migrations package into your own app, but also example code of how to configure and use migrations if you do want to embed the library your application (recommended, so you can run migrations on deployment).

Migrations Integration and CLI

The migrations package may be included in your product binary, or run separately as a standalone application. When embedded in the application, typically you configure your application to apply the database migrations on startup.

It may also be run as a standalone tool, either from the command line or a Docker container.

Installing the Command-Line Tool

To install the command-line tool, run:

$ go install github.com/sbowman/migrations/v2/migrate

This will install the migrate binary into your $GOPATH/bin directory. If that directory is on your PATH, you should be able to run migrations from anywhere.

If you need help using the command-line tool, run migrate help for information.

Available Options

To apply migrations to the database schema, you need to supply two pieces of information: the path to the SQL migrations, and the database URI to connect to the database. To supply that information to the command-line application, use the migrations and uri parameters:

$ migrate apply --uri='postgres://postgres@127.0.0.1/fourier?sslmode=disable&connect_timeout=5'
--migrations=./sql

By default, the migrations package looks for migrations in the sql directory relative to where you run the binary, so you can leave --migrations off:

$ migrate apply --uri='postgres://postgres@127.0.0.1/fourier?sslmode=disable&connect_timeout=5'

You may additionally apply a revision to migrate the database to the specific version of the schema using the --revision parameter:

$ migrate apply --uri='postgres://postgres@127.0.0.1/fourier?sslmode=disable&connect_timeout=5'
--revision=23

This will either apply the migrations to reach SQL migration file 23-<name>.sql, or rollback the database migrations to step back down to revision 23.

Supported Environment Variables

The migrations package supports supplying configuration options via environment variables.

• To supply an alternative migrations directory, you can use the MIGRATIONS environment variable.
• To supply the PostgreSQL URI in the command-line application, you can use the DB_URI or DB environment variables.