Safe Haskell	None
Language	GHC2024

Arbiter.Migrations

Contents

Configuration
Tracked Migrations
Re-exports

Description

Versioned, tracked migrations for job queue schemas.

Uses the postgresql-migration library to:

Track which migrations have been run in a database table
Run migrations in order
Prevent re-running completed migrations
Support incremental schema changes

Migration history is stored in a schema_migrations table inside the target schema (e.g., arbiter.schema_migrations).

Synopsis

data MigrationConfig = MigrationConfig {
- enableNotifications :: Bool
- enableEventStreaming :: Bool
}
defaultMigrationConfig :: MigrationConfig
runMigrationsForRegistry :: forall (registry :: JobPayloadRegistry). RegistryTables registry => Proxy registry -> ByteString -> SchemaName -> MigrationConfig -> IO (MigrationResult String)
runMigrationsTrackedForTables :: ByteString -> SchemaName -> [TableName] -> MigrationConfig -> IO (MigrationResult String)
jobQueueMigrationsForTable :: SchemaName -> TableName -> MigrationConfig -> [MigrationCommand]
data MigrationResult a
- = MigrationError a
- | MigrationSuccess

Configuration

data MigrationConfig Source #

Configuration for job queue migrations

Controls which optional features are enabled when creating job queue tables.

Constructors

MigrationConfig

Fields

enableNotifications :: Bool
Whether to create LISTEN/NOTIFY triggers for reactive job claiming. When enabled, workers can subscribe to notifications instead of polling. Default: True
enableEventStreaming :: Bool
Whether to create event streaming triggers for the admin UI. When enabled, every INSERT/UPDATE/DELETE on job tables fires an enriched JSON event via pg_notify on the arbiter_job_events channel. This adds overhead to every row operation - disable for maximum throughput. Default: False

Instances

Instances details

Show MigrationConfig Source #
Instance details Defined in Arbiter.Migrations Methods showsPrec :: Int -> MigrationConfig -> ShowS # show :: MigrationConfig -> String # showList :: [MigrationConfig] -> ShowS #
Eq MigrationConfig Source #
Instance details Defined in Arbiter.Migrations Methods (==) :: MigrationConfig -> MigrationConfig -> Bool # (/=) :: MigrationConfig -> MigrationConfig -> Bool #

defaultMigrationConfig :: MigrationConfig Source #

Default migration configuration

Tracked Migrations

runMigrationsForRegistry Source #

Arguments

:: forall (registry :: JobPayloadRegistry). RegistryTables registry
=> Proxy registry	Proxy for the job payload registry
-> ByteString	Database connection string
-> SchemaName	Schema name
-> MigrationConfig	Migration configuration
-> IO (MigrationResult String)	Migration results

Run migrations for all tables in a queue registry.

Creates tables for each payload type in the registry (main + DLQ) within a single PostgreSQL schema. The schema itself is created first, outside of migration tracking. PostgreSQL notices are suppressed during migration.

Example:

type AppRegistry =
  '[ '("email_jobs", EmailPayload)
   , '("order_jobs", OrderPayload)
   ]

main :: IO ()
main = do
  result <- runMigrationsForRegistry
              (Proxy @AppRegistry)
              "host=localhost dbname=mydb"
              "arbiter"
              defaultMigrationConfig

runMigrationsTrackedForTables Source #

Arguments

:: ByteString	Database connection string
-> SchemaName	Schema name
-> [TableName]	Table names to create
-> MigrationConfig	Migration configuration
-> IO (MigrationResult String)

Run migrations for multiple tables within a single schema.

jobQueueMigrationsForTable Source #

Arguments

:: SchemaName	Schema name
-> TableName	Table name
-> MigrationConfig	Migration configuration
-> [MigrationCommand]	List of migration commands

All job queue migrations for a single table

This creates migrations for one table and its DLQ within a schema. Each table gets its own set of migrations with unique version identifiers.

Re-exports

data MigrationResult a #

Constructors

MigrationError a
MigrationSuccess

Instances

Instances details

Functor MigrationResult
Instance details Defined in Database.PostgreSQL.Simple.Migration Methods fmap :: (a -> b) -> MigrationResult a -> MigrationResult b # (<$) :: a -> MigrationResult b -> MigrationResult a #
Foldable MigrationResult
Instance details Defined in Database.PostgreSQL.Simple.Migration Methods fold :: Monoid m => MigrationResult m -> m # foldMap :: Monoid m => (a -> m) -> MigrationResult a -> m # foldMap' :: Monoid m => (a -> m) -> MigrationResult a -> m # foldr :: (a -> b -> b) -> b -> MigrationResult a -> b # foldr' :: (a -> b -> b) -> b -> MigrationResult a -> b # foldl :: (b -> a -> b) -> b -> MigrationResult a -> b # foldl' :: (b -> a -> b) -> b -> MigrationResult a -> b # foldr1 :: (a -> a -> a) -> MigrationResult a -> a # foldl1 :: (a -> a -> a) -> MigrationResult a -> a # toList :: MigrationResult a -> [a] # null :: MigrationResult a -> Bool # length :: MigrationResult a -> Int # elem :: Eq a => a -> MigrationResult a -> Bool # maximum :: Ord a => MigrationResult a -> a # minimum :: Ord a => MigrationResult a -> a # sum :: Num a => MigrationResult a -> a # product :: Num a => MigrationResult a -> a #
Traversable MigrationResult
Instance details Defined in Database.PostgreSQL.Simple.Migration Methods traverse :: Applicative f => (a -> f b) -> MigrationResult a -> f (MigrationResult b) # sequenceA :: Applicative f => MigrationResult (f a) -> f (MigrationResult a) # mapM :: Monad m => (a -> m b) -> MigrationResult a -> m (MigrationResult b) # sequence :: Monad m => MigrationResult (m a) -> m (MigrationResult a) #
Read a => Read (MigrationResult a)
Instance details Defined in Database.PostgreSQL.Simple.Migration Methods readsPrec :: Int -> ReadS (MigrationResult a) # readList :: ReadS [MigrationResult a] # readPrec :: ReadPrec (MigrationResult a) # readListPrec :: ReadPrec [MigrationResult a] #
Show a => Show (MigrationResult a)
Instance details Defined in Database.PostgreSQL.Simple.Migration Methods showsPrec :: Int -> MigrationResult a -> ShowS # show :: MigrationResult a -> String # showList :: [MigrationResult a] -> ShowS #
Eq a => Eq (MigrationResult a)
Instance details Defined in Database.PostgreSQL.Simple.Migration Methods (==) :: MigrationResult a -> MigrationResult a -> Bool # (/=) :: MigrationResult a -> MigrationResult a -> Bool #
Ord a => Ord (MigrationResult a)
Instance details Defined in Database.PostgreSQL.Simple.Migration Methods compare :: MigrationResult a -> MigrationResult a -> Ordering # (<) :: MigrationResult a -> MigrationResult a -> Bool # (<=) :: MigrationResult a -> MigrationResult a -> Bool # (>) :: MigrationResult a -> MigrationResult a -> Bool # (>=) :: MigrationResult a -> MigrationResult a -> Bool # max :: MigrationResult a -> MigrationResult a -> MigrationResult a # min :: MigrationResult a -> MigrationResult a -> MigrationResult a #