cigogne

Types

DatabaseConfig

The configuration used to create a MigrationEngine

pub type DatabaseConfig {
  EnvVarConfig
  UrlConfig(url: String)
  PogConfig(config: pog.Config)
  ConnectionConfig(connection: pog.Connection)
}

Constructors

```
EnvVarConfig
```
The default configuration. It uses the DATABASE_URL envvar to connect
```
UrlConfig(url: String)
```
A configuration using the URL to the database
```
PogConfig(config: pog.Config)
```
A configuration using a pog.Config to connect. It disables schema generation.
```
ConnectionConfig(connection: pog.Connection)
```
A configuration using a pog.Connection directly. It disables schema generation.

MigrationEngine

</>

The MigrationEngine contains all the data required to apply and roll back migrations.

pub type MigrationEngine {
  MigrationEngine(
    db_url: option.Option(String),
    connection: pog.Connection,
    applied: List(types.Migration),
    files: List(types.Migration),
    zero_applied: Bool,
  )
}

Constructors

MigrationEngine(
  db_url: option.Option(String),
  connection: pog.Connection,
  applied: List(types.Migration),
  files: List(types.Migration),
  zero_applied: Bool,
)

Values

apply_migration

</>

pub fn apply_migration(
  engine: MigrationEngine,
  migration: types.Migration,
) -> Result(Nil, types.MigrateError)

Apply a migration to the database. This function does not create a schema file.

apply_migration_if_not_applied

</>

pub fn apply_migration_if_not_applied(
  engine: MigrationEngine,
  migration: types.Migration,
) -> Result(Nil, types.MigrateError)

Apply a migration to the database if it hasn’t been applied. This function does not create a schema file.

apply_next_migration

</>

pub fn apply_next_migration(
  engine: MigrationEngine,
) -> Result(Nil, types.MigrateError)

Apply the next migration that wasn’t applied yet. The migrations are acquired from priv/migrations/*.sql files. This function does not create a schema file.

create_migration_engine

</>

pub fn create_migration_engine(
  config: DatabaseConfig,
) -> Result(MigrationEngine, types.MigrateError)

Creates a MigrationEngine from a configuration. This function will try to connect to the database. Then it will fetch the applied migrations and the existing migration files.

create_zero_migration

</>

pub fn create_zero_migration(
  name: String,
  queries_up: List(String),
  queries_down: List(String),
) -> types.Migration

Create a “zero” migration that should be applied before the user’s migrations

execute_migrations_to_last

</>

pub fn execute_migrations_to_last(
  engine: MigrationEngine,
) -> Result(Nil, types.MigrateError)

Apply migrations until we reach the last defined migration. The migrations are acquired from priv/migrations/*.sql files. This function does not create a schema file.

execute_n_migrations

</>

pub fn execute_n_migrations(
  engine: MigrationEngine,
  count: Int,
) -> Result(Nil, types.MigrateError)

Apply or roll back migrations until we reach the migration corresponding to the provided number. The migrations are acquired from priv/migrations/*.sql files. This function does not create a schema file.

get_migrations

</>

pub fn get_migrations(
  ,
) -> Result(List(types.Migration), types.MigrateError)

Get all defined migrations in your project. Migration files are searched in the priv/migrations folder.

get_schema

</>

pub fn get_schema(
  url: String,
) -> Result(String, types.MigrateError)

Get details about the schema of the database at the provided url.

is_zero_migration

</>

pub fn is_zero_migration(migration: types.Migration) -> Bool

Checks if a migration is a zero migration (has been created with create_zero_migration)

main

</>

pub fn main() -> Result(Nil, Nil)

migrate_down

</>

pub fn migrate_down() -> Result(Nil, types.MigrateError)

Roll back the last applied migration. This function will get the database url from the DATABASE_URL environment variable. The migrations are then acquired from priv/migrations/*.sql files. If successful, it will also create a file and write details of the new schema in it.

migrate_n

</>

pub fn migrate_n(count: Int) -> Result(Nil, types.MigrateError)

Apply or roll back migrations until we reach the migration corresponding to the provided number. This function will get the database url from the DATABASE_URL environment variable. The migrations are then acquired from priv/migrations/*.sql files. If successful, it will also create a file and write details of the new schema in it.

migrate_to_last

</>

pub fn migrate_to_last() -> Result(Nil, types.MigrateError)

Apply migrations until we reach the last defined migration. This function will get the database url from the DATABASE_URL environment variable. The migrations are then acquired from priv/migrations/*.sql files. If successful, it will also create a file and write details of the new schema in it.

migrate_up

</>

pub fn migrate_up() -> Result(Nil, types.MigrateError)

Apply the next migration that wasn’t applied yet. This function will get the database url from the DATABASE_URL environment variable. The migrations are then acquired from priv/migrations/*.sql files. If successful, it will also create a file and write details of the new schema in it.

new_migration

</>

pub fn new_migration(
  name: String,
) -> Result(Nil, types.MigrateError)

Create a new migration file in the priv/migrations folder with the provided name.

print_error

</>

pub fn print_error(error: types.MigrateError) -> Nil

Print a MigrateError to the standard error stream.

roll_back_migration

</>

pub fn roll_back_migration(
  engine: MigrationEngine,
  migration: types.Migration,
) -> Result(Nil, types.MigrateError)

Roll back a migration from the database. This function does not create a schema file.

roll_back_previous_migration

</>

pub fn roll_back_previous_migration(
  engine: MigrationEngine,
) -> Result(Nil, types.MigrateError)

Roll back the last applied migration. The migrations are acquired from priv/migrations/*.sql files. This function does not create a schema file.

timestamp_format

</>

pub const timestamp_format: tempo.NaiveDateTimeFormat

update_schema

</>

pub fn update_schema(
  engine: MigrationEngine,
) -> Result(Nil, types.MigrateError)

Create or update a schema file if the engine configuration permits it. See update_schema_file.

update_schema_file

</>

pub fn update_schema_file(
  url: String,
) -> Result(Nil, types.MigrateError)

Create or update a schema file with details of the schema of the database at the provided url. The schema file is created at ./sql.schema.

verify_applied_migration_hashes

</>

pub fn verify_applied_migration_hashes(
  engine: MigrationEngine,
) -> Result(Nil, types.MigrateError)

Verify the hash integrity of applied migrations. If an already applied migration has been modified, it should most likely be run again by the user.