Freckle.App.Csv

Stream, parse, and validate CSVs

A minor extension of cassava. Using MonadValidate and Conduit.

Documentation

csvWithValidationSink

Arguments

:: forall a b err m. (MonadThrow m, MonadUnliftIO m, PrimMonad m, ValidateHeader a, FromNamedRecord a)

=> ConduitT () ByteString (ResourceT m) ()

CSV as a byte stream

-> (Vector a -> Validate (NonEmpty (CsvException err)) (Vector b))

Validation to apply to resulting rows

-> m (Validate (NonEmpty (CsvException err)) (Vector b))

Stream parse a CSV

• Expects UTF-8
• Provides incremental validation

csvWithParserAndValidationSink

Arguments

:: forall a b err m. (MonadThrow m, MonadUnliftIO m, PrimMonad m)

=> (Header -> Validate (NESeq String) ())

-> (NamedRecord -> Parser a)

Custom record parser

-> ConduitT () ByteString (ResourceT m) ()

CSV as a byte stream

-> (Vector a -> Validate (NonEmpty (CsvException err)) (Vector b))

Validation to apply to resulting rows

-> m (Validate (NonEmpty (CsvException err)) (Vector b))

Stream parse a CSV with a custom parser

• Expects UTF-8
• Provides incremental validation

Conduit Primitives

runCsvConduit :: forall r m err. MonadUnliftIO m => ConduitT () Void (ValidateT (Seq (CsvException err)) (ResourceT m)) r -> m (Either (Seq (CsvException err)) r)

Run a CSV conduit handling invalid UTF8

decodeCsv :: forall a m err. (MonadThrow m, MonadValidate (Seq (CsvException err)) m, ValidateHeader a, FromNamedRecord a) => ConduitT ByteString a m ()

Stream in ByteStrings and parse records in constant space

Header Validation

class ValidateHeader a

Minimal complete definition

validateHeader

validateHeader :: (ValidateHeader a, Bind m, Monad m) => proxy a -> Header -> ValidateT (NESeq String) m ()

hasHeader :: Monad m => Header -> Name -> ValidateT (NESeq String) m ()

defaultValidateOrderedHeader :: forall a proxy m. (DefaultOrdered a, Monad m) => proxy a -> Header -> ValidateT (NESeq String) m ()

Exceptions

data CsvException a

Constructors

CsvMissingColumn !Text

CsvParseException !Int !Text

CsvFileNotFound

CsvUnknownFileEncoding

CsvExceptionExtension a

A constructor for providing extensible csv exceptions

Instances

ToJSON a => ToJSON (CsvException a)

Defined in Freckle.App.Csv

Methods

toJSON :: CsvException a -> Value

toEncoding :: CsvException a -> Encoding

toJSONList :: [CsvException a] -> Value

toEncodingList :: [CsvException a] -> Encoding

Show a => Show (CsvException a)

Defined in Freckle.App.Csv

Methods

showsPrec :: Int -> CsvException a -> ShowS

show :: CsvException a -> String

showList :: [CsvException a] -> ShowS

Eq a => Eq (CsvException a)

Defined in Freckle.App.Csv

Methods

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

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

Options

defaultOptions :: Options

Default conversion options.

  Options
  { fieldLabelModifier = id
  }
  

Since: cassava-0.5.1.0