Database.PostgreSQL.Simple.Migration

A migration library for postgresql-simple.

For usage, see Readme.markdown.

Migration actions

defaultOptions :: MigrationOptions

runMigration :: Connection -> MigrationOptions -> MigrationCommand -> IO (MigrationResult String)

Executes migrations inside the provided MigrationContext.

Returns MigrationSuccess if the provided MigrationCommand executes without error. If an error occurs, execution is stopped and a MigrationError is returned.

runMigrations

Arguments

:: Connection

The postgres connection to use

-> MigrationOptions

The options for this migration

-> [MigrationCommand]

The commands to run

-> IO (MigrationResult String)

Execute a sequence of migrations

Returns MigrationSuccess if all of the provided MigrationCommands execute without error. If an error occurs, execution is stopped and the MigrationError is returned.

sequenceMigrations :: Monad m => [m (MigrationResult e)] -> m (MigrationResult e)

Run a sequence of contexts, stopping on the first failure

Migration types

type Checksum = ByteString

The checksum type of a migration script.

data MigrationOptions

Constructors

MigrationOptions

Fields

• optVerbose :: !Verbosity

  Verbosity of the library.

• optTableName :: !ByteString

  The name of the table that stores the migrations, usually "schema_migrations"

• optLogWriter :: !(Either Text Text -> IO ())

  Logger. Either indicates log level, Left for an error message and Right for an info message.

• optTransactionControl :: !TransactionControl

  If/when transactions should be started

data MigrationCommand

MigrationCommand determines the action of the runMigration script.

Constructors

MigrationInitialization

Initializes the database with a helper table containing meta information.

MigrationDirectory FilePath

Executes migrations based on SQL scripts in the provided FilePath in alphabetical order.

MigrationFile ScriptName FilePath

Executes a migration based on script located at the provided FilePath.

MigrationScript ScriptName ByteString

Executes a migration based on the provided bytestring.

MigrationValidation MigrationCommand

Validates that the provided MigrationCommand has been executed.

MigrationCommands [MigrationCommand]

Performs a series of MigrationCommands in sequence.

Instances

Eq MigrationCommand

Defined in Database.PostgreSQL.Simple.Migration

Methods

(==) :: MigrationCommand -> MigrationCommand -> Bool

(/=) :: MigrationCommand -> MigrationCommand -> Bool

Ord MigrationCommand

Defined in Database.PostgreSQL.Simple.Migration

Methods

compare :: MigrationCommand -> MigrationCommand -> Ordering

(<) :: MigrationCommand -> MigrationCommand -> Bool

(<=) :: MigrationCommand -> MigrationCommand -> Bool

(>) :: MigrationCommand -> MigrationCommand -> Bool

(>=) :: MigrationCommand -> MigrationCommand -> Bool

max :: MigrationCommand -> MigrationCommand -> MigrationCommand

min :: MigrationCommand -> MigrationCommand -> MigrationCommand

Read MigrationCommand

Defined in Database.PostgreSQL.Simple.Migration

Methods

readsPrec :: Int -> ReadS MigrationCommand

readList :: ReadS [MigrationCommand]

readPrec :: ReadPrec MigrationCommand

readListPrec :: ReadPrec [MigrationCommand]

Show MigrationCommand

Defined in Database.PostgreSQL.Simple.Migration

Methods

showsPrec :: Int -> MigrationCommand -> ShowS

show :: MigrationCommand -> String

showList :: [MigrationCommand] -> ShowS

Semigroup MigrationCommand

Defined in Database.PostgreSQL.Simple.Migration

Methods

(<>) :: MigrationCommand -> MigrationCommand -> MigrationCommand

sconcat :: NonEmpty MigrationCommand -> MigrationCommand

stimes :: Integral b => b -> MigrationCommand -> MigrationCommand

Monoid MigrationCommand

Defined in Database.PostgreSQL.Simple.Migration

Methods

mempty :: MigrationCommand

mappend :: MigrationCommand -> MigrationCommand -> MigrationCommand

mconcat :: [MigrationCommand] -> MigrationCommand

data MigrationResult a

A sum-type denoting the result of a migration.

Constructors

MigrationError a

There was an error in script migration.

MigrationSuccess

All scripts have been executed successfully.

Instances

Functor MigrationResult

Defined in Database.PostgreSQL.Simple.Migration

Methods

fmap :: (a -> b) -> MigrationResult a -> MigrationResult b

(<$) :: a -> MigrationResult b -> MigrationResult a

Foldable MigrationResult

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

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)

Eq a => Eq (MigrationResult a)

Defined in Database.PostgreSQL.Simple.Migration

Methods

(==) :: MigrationResult a -> MigrationResult a -> Bool

(/=) :: MigrationResult a -> MigrationResult a -> Bool

Ord a => Ord (MigrationResult a)

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

Read a => Read (MigrationResult a)

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)

Defined in Database.PostgreSQL.Simple.Migration

Methods

showsPrec :: Int -> MigrationResult a -> ShowS

show :: MigrationResult a -> String

showList :: [MigrationResult a] -> ShowS

type ScriptName = String

The name of a script. Typically the filename or a custom name when using Haskell migrations.

data TransactionControl

Determines how transactions are handled Its is recommened to use transaction when running migrations Certain actions require a transaction per script, if you are doing this use TransactionPerStep If you want a single transaction for all migrations use TransactionPerRun If you do not want a transaction, or are using an existing transaction then use NoNewTransaction

Constructors

NoNewTransaction

No new transaction will be started. Up to the caller to decide if the run is in a transaction or not

TransactionPerRun

Call withTransaction once for the entire MigrationCommand

TransactionPerStep

Call withTransaction once for each step in a MigrationCommand (i.e. new transaction per script)

Instances

Show TransactionControl

Defined in Database.PostgreSQL.Simple.Migration

Methods

showsPrec :: Int -> TransactionControl -> ShowS

show :: TransactionControl -> String

showList :: [TransactionControl] -> ShowS

data Verbosity

Constructors

Verbose

Quiet

Instances

Eq Verbosity

Defined in Database.PostgreSQL.Simple.Migration

Methods

(==) :: Verbosity -> Verbosity -> Bool

(/=) :: Verbosity -> Verbosity -> Bool

Show Verbosity

Defined in Database.PostgreSQL.Simple.Migration

Methods

showsPrec :: Int -> Verbosity -> ShowS

show :: Verbosity -> String

showList :: [Verbosity] -> ShowS

Migration result actions

getMigrations :: Connection -> IO [SchemaMigration]

Produces a list of all executed SchemaMigrations in the default schema_migrations table

getMigrations' :: Connection -> ByteString -> IO [SchemaMigration]

Produces a list of all executed SchemaMigrations.

Migration result types

data SchemaMigration

A product type representing a single, executed SchemaMigration.

Constructors

SchemaMigration

Fields

• schemaMigrationName :: ByteString

  The name of the executed migration.

• schemaMigrationChecksum :: Checksum

  The calculated MD5 checksum of the executed script.

• schemaMigrationExecutedAt :: LocalTime

  A timestamp without timezone of the date of execution of the script.

Instances

Eq SchemaMigration

Defined in Database.PostgreSQL.Simple.Migration

Methods

(==) :: SchemaMigration -> SchemaMigration -> Bool

(/=) :: SchemaMigration -> SchemaMigration -> Bool

Ord SchemaMigration

Defined in Database.PostgreSQL.Simple.Migration

Methods

compare :: SchemaMigration -> SchemaMigration -> Ordering

(<) :: SchemaMigration -> SchemaMigration -> Bool

(<=) :: SchemaMigration -> SchemaMigration -> Bool

(>) :: SchemaMigration -> SchemaMigration -> Bool

(>=) :: SchemaMigration -> SchemaMigration -> Bool

max :: SchemaMigration -> SchemaMigration -> SchemaMigration

min :: SchemaMigration -> SchemaMigration -> SchemaMigration

Read SchemaMigration

Defined in Database.PostgreSQL.Simple.Migration

Methods

readsPrec :: Int -> ReadS SchemaMigration

readList :: ReadS [SchemaMigration]

readPrec :: ReadPrec SchemaMigration

readListPrec :: ReadPrec [SchemaMigration]

Show SchemaMigration

Defined in Database.PostgreSQL.Simple.Migration

Methods

showsPrec :: Int -> SchemaMigration -> ShowS

show :: SchemaMigration -> String

showList :: [SchemaMigration] -> ShowS

FromRow SchemaMigration

Defined in Database.PostgreSQL.Simple.Migration

Methods

fromRow :: RowParser SchemaMigration

ToRow SchemaMigration

Defined in Database.PostgreSQL.Simple.Migration

Methods

toRow :: SchemaMigration -> [Action]