-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | PostgreSQL Schema Migrations
--   
--   A PostgreSQL-simple schema migration utility
@package postgresql-simple-migration
@version 0.1.15.0


-- | A collection of utilites for database migrations.
module Database.PostgreSQL.Simple.Util

-- | Checks if the table with the given name exists in the database.
existsTable :: Connection -> String -> IO Bool

-- | Executes the given IO monad inside a transaction and performs a
--   roll-back afterwards (even if exceptions occur).
withTransactionRolledBack :: Connection -> IO a -> IO a


-- | A migration library for postgresql-simple.
--   
--   For usage, see Readme.markdown.
module Database.PostgreSQL.Simple.Migration

-- | Executes migrations inside the provided <a>MigrationContext</a>.
--   
--   Returns <a>MigrationSuccess</a> if the provided
--   <a>MigrationCommand</a> executes without error. If an error occurs,
--   execution is stopped and a <a>MigrationError</a> is returned.
--   
--   It is recommended to wrap <a>runMigration</a> inside a database
--   transaction.
runMigration :: MigrationContext -> IO (MigrationResult String)

-- | Execute a sequence of migrations
--   
--   Returns <a>MigrationSuccess</a> if all of the provided
--   <a>MigrationCommand</a>s execute without error. If an error occurs,
--   execution is stopped and the <a>MigrationError</a> is returned.
--   
--   It is recommended to wrap <a>runMigrations</a> inside a database
--   transaction.
runMigrations :: Bool -> Connection -> [MigrationCommand] -> IO (MigrationResult String)

-- | Run a sequence of contexts, stopping on the first failure
sequenceMigrations :: Monad m => [m (MigrationResult e)] -> m (MigrationResult e)

-- | The <a>MigrationContext</a> provides an execution context for
--   migrations.
data MigrationContext
MigrationContext :: MigrationCommand -> Bool -> Connection -> MigrationContext

-- | The action that will be performed by <a>runMigration</a>
[migrationContextCommand] :: MigrationContext -> MigrationCommand

-- | Verbosity of the library.
[migrationContextVerbose] :: MigrationContext -> Bool

-- | The PostgreSQL connection to use for migrations.
[migrationContextConnection] :: MigrationContext -> Connection

-- | <a>MigrationCommand</a> determines the action of the
--   <a>runMigration</a> script.
data MigrationCommand

-- | Initializes the database with a helper table containing meta
--   information.
MigrationInitialization :: MigrationCommand

-- | Executes migrations based on SQL scripts in the provided
--   <a>FilePath</a> in alphabetical order.
MigrationDirectory :: FilePath -> MigrationCommand

-- | Executes a migration based on script located at the provided
--   <a>FilePath</a>.
MigrationFile :: ScriptName -> FilePath -> MigrationCommand

-- | Executes a migration based on the provided bytestring.
MigrationScript :: ScriptName -> ByteString -> MigrationCommand

-- | Validates that the provided MigrationCommand has been executed.
MigrationValidation :: MigrationCommand -> MigrationCommand

-- | Performs a series of <a>MigrationCommand</a>s in sequence.
MigrationCommands :: [MigrationCommand] -> MigrationCommand

-- | A sum-type denoting the result of a migration.
data MigrationResult a

-- | There was an error in script migration.
MigrationError :: a -> MigrationResult a

-- | All scripts have been executed successfully.
MigrationSuccess :: MigrationResult a

-- | The name of a script. Typically the filename or a custom name when
--   using Haskell migrations.
type ScriptName = String

-- | The checksum type of a migration script.
type Checksum = ByteString

-- | Produces a list of all executed <a>SchemaMigration</a>s.
getMigrations :: Connection -> IO [SchemaMigration]

-- | A product type representing a single, executed <a>SchemaMigration</a>.
data SchemaMigration
SchemaMigration :: ByteString -> Checksum -> LocalTime -> SchemaMigration

-- | The name of the executed migration.
[schemaMigrationName] :: SchemaMigration -> ByteString

-- | The calculated MD5 checksum of the executed script.
[schemaMigrationChecksum] :: SchemaMigration -> Checksum

-- | A timestamp without timezone of the date of execution of the script.
[schemaMigrationExecutedAt] :: SchemaMigration -> LocalTime
instance GHC.Read.Read Database.PostgreSQL.Simple.Migration.SchemaMigration
instance GHC.Classes.Eq Database.PostgreSQL.Simple.Migration.SchemaMigration
instance GHC.Show.Show Database.PostgreSQL.Simple.Migration.SchemaMigration
instance Data.Traversable.Traversable Database.PostgreSQL.Simple.Migration.MigrationResult
instance Data.Foldable.Foldable Database.PostgreSQL.Simple.Migration.MigrationResult
instance GHC.Base.Functor Database.PostgreSQL.Simple.Migration.MigrationResult
instance GHC.Classes.Ord a => GHC.Classes.Ord (Database.PostgreSQL.Simple.Migration.MigrationResult a)
instance GHC.Read.Read a => GHC.Read.Read (Database.PostgreSQL.Simple.Migration.MigrationResult a)
instance GHC.Classes.Eq a => GHC.Classes.Eq (Database.PostgreSQL.Simple.Migration.MigrationResult a)
instance GHC.Show.Show a => GHC.Show.Show (Database.PostgreSQL.Simple.Migration.MigrationResult a)
instance GHC.Classes.Ord Database.PostgreSQL.Simple.Migration.CheckScriptResult
instance GHC.Read.Read Database.PostgreSQL.Simple.Migration.CheckScriptResult
instance GHC.Classes.Eq Database.PostgreSQL.Simple.Migration.CheckScriptResult
instance GHC.Show.Show Database.PostgreSQL.Simple.Migration.CheckScriptResult
instance GHC.Classes.Ord Database.PostgreSQL.Simple.Migration.MigrationCommand
instance GHC.Read.Read Database.PostgreSQL.Simple.Migration.MigrationCommand
instance GHC.Classes.Eq Database.PostgreSQL.Simple.Migration.MigrationCommand
instance GHC.Show.Show Database.PostgreSQL.Simple.Migration.MigrationCommand
instance GHC.Classes.Ord Database.PostgreSQL.Simple.Migration.SchemaMigration
instance Database.PostgreSQL.Simple.FromRow.FromRow Database.PostgreSQL.Simple.Migration.SchemaMigration
instance Database.PostgreSQL.Simple.ToRow.ToRow Database.PostgreSQL.Simple.Migration.SchemaMigration
instance GHC.Base.Semigroup Database.PostgreSQL.Simple.Migration.MigrationCommand
instance GHC.Base.Monoid Database.PostgreSQL.Simple.Migration.MigrationCommand