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:

Note: No features are enabled by default

• 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<std::error::Error>>. See the embedded_programmable example for a working sample of function migrations.
• When working with embedded and function migrations, the respective database feature must be enabled (d-postgres / d-sqlite / d-mysql).

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

fn down(_: migrant_lib::ConnConfig) -> Result<(), Box<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(),
])?;

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.

See CONTRIBUTING

License: MIT