-- 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 0.1.2.0


-- | 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


-- | 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)

-- | 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 the provided MigrationCommand.
MigrationValidation :: 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 Show MigrationCommand
instance Eq MigrationCommand
instance Read MigrationCommand
instance Ord MigrationCommand
instance Show CheckScriptResult
instance Eq CheckScriptResult
instance Read CheckScriptResult
instance Ord CheckScriptResult
instance Show a => Show (MigrationResult a)
instance Eq a => Eq (MigrationResult a)
instance Read a => Read (MigrationResult a)
instance Ord a => Ord (MigrationResult a)
instance Show SchemaMigration
instance Eq SchemaMigration
instance Read SchemaMigration
instance ToRow SchemaMigration
instance FromRow SchemaMigration
instance Ord SchemaMigration