lode/migrator

Runs migrations against a repo and tracks applied versions in a schema_migrations table — the Ecto.Migrator equivalent. Each migration runs in its own transaction, so a failed migration rolls back cleanly.

Call the library functions directly, or use run to build a CLI:

migrator.migrate(repo, all_migrations()) migrator.rollback(repo, all_migrations(), steps: 1) migrator.status(repo, all_migrations())

run parses migrate / rollback [n] / status from argv-style args and prints the result — wire it up in your own main:

pub fn main() { let repo = repo.new(postgres.new(connect())) let assert Ok(_) = migrator.run(repo, all_migrations(), argv.load().arguments) }

Requires an adapter that supports execute_ddl/query_sql (the Postgres and SQLite adapters; the in-memory adapter does not). The DDL dialect is inferred from the adapter’s engine tag.

pub type MigrationStatus {
  MigrationStatus(version: Int, applied: Bool)
}

pub fn migrate(
  repo r: repo.Repo,
  migrations migrations: List(migration.Migration),
) -> Result(List(Int), error.LodeError)

pub fn rollback(
  repo r: repo.Repo,
  migrations migrations: List(migration.Migration),
  steps steps: Int,
) -> Result(List(Int), error.LodeError)

pub fn run(
  repo r: repo.Repo,
  migrations migrations: List(migration.Migration),
  args args: List(String),
) -> Result(Nil, error.LodeError)

pub fn status(
  repo r: repo.Repo,
  migrations migrations: List(migration.Migration),
) -> Result(List(MigrationStatus), error.LodeError)