migrant_lib

Embeddable migration management

Also see migrant CLI

migrant_lib allows defining and embedding management of database migrations and (connection) configuration in your compiled application.

Available Features:

Notes:

• No features are enabled by default

• As of 0.20.0 the d-sqlite feature does not use rusqlites bundled feature. If you would like sqlite to be bundled with your application, you will have to include rusqlite and enable the bundled feature in your project.

Usage

• You must enable the database features relevant to your usecase (d-postgres / d-sqlite / d-mysql).

• Migrations can be defined as files, string literals, or functions.

• File migrations can be either read from files at runtime or embedded in your executable at compile time (using include_str!).

• Migration tags must all be unique and may only contain the characters [a-z0-9-]. When running in a cli_compatible mode (see Config::use_cli_compatible_tags), tags must also be prefixed with a timestamp, following: [0-9]{14}_[a-z0-9-]+. See the embedded_cli_compatible example.

• Function migrations must have the signature fn(ConnConfig) -> Result<(), Box<dyn std::error::Error>>. See the embedded_programmable example for a working sample of function migrations.

• When d-postgres is enabled, you can specify a custom/self-signed ssl certificate using PostgresSettingsBuilder::ssl_cert_file or setting ssl_cert_file = "..." in your Migrant.toml.

fn up(_: migrant_lib::ConnConfig) -> Result<(), Box<dyn std::error::Error>> {
    print!(" Up!");
    Ok(())
}

fn down(_: migrant_lib::ConnConfig) -> Result<(), Box<dyn std::error::Error>> {
    print!(" Down!");
    Ok(())
}

config.use_migrations(&[
    migrant_lib::FileMigration::with_tag("create-users-table")
        .up("migrations/embedded/create_users_table/up.sql")?
        .down("migrations/embedded/create_users_table/down.sql")?
        .boxed(),
    migrant_lib::EmbeddedMigration::with_tag("create-places-table")
        .up(include_str!("../migrations/embedded/create_places_table/up.sql"))
        .down(include_str!("../migrations/embedded/create_places_table/down.sql"))
        .boxed(),
    migrant_lib::FnMigration::with_tag("custom")
        .up(up)
        .down(down)
        .boxed(),
])?;

CLI Compatibility

Migration management identical to the migrant CLI tool can also be embedded. This method only supports file-based migrations (so FileMigrations or EmbeddedMigrations using include_str!) and those migration files names must be timestamped with the format [0-9]{14}_[a-z0-9-]+, Properly named files can be generated by migrant_lib::new or the migrant CLI tool. This is required because migration order is implied by file names which must follow a specific format and contain a valid timestamp.

See the migrant_cli_compatible example for a working sample where migration files and a Migrant.toml config file are available at runtime.

See the embedded_cli_compatible example for a working sample where the migrant CLI tool can be used during development, and database configuration and migration file contents are embedded in the application.

Development

See CONTRIBUTING

License: MIT