scodec

Combinator library for working with binary data.

The primary abstraction of this library is Codec, which provides the ability to encode/decode values to/from binary.

There are more general abstractions though, such as Encoder and Decoder. There's also GenCodec which extends both Encoder and Decoder but allows the types to vary. Given these more general abstractions, a Codec[A] can be represented as a GenCodec[A, A].

The more general abstractions are important because they allow operations on codecs that would not otherwise be possible. For example, given a Codec[A], mapping a function A => B over the codec yields a GenCodec[A, B]. Without the more general abstractions, map is impossible to define (e.g., how would codec.map(f).encode(b) be implemented?). Given a GenCodec[A, B], the encoding functionality can be ignored by treating it as a Decoder[B], or the encoding type can be changed via contramap. If after further transformations, the two types to GenCodec are equal, we can reconstitute a Codec from the GenCodec by calling fuse.

See the codecs package object for pre-defined codecs for many common data types and combinators for building larger codecs out of smaller ones.

For the categorically minded, note the following:

Decoder is a monad
Encoder is a contravariant functor
GenCodec is a profunctor
Codec is an invariant functor

Source: package.scala

Linear Supertypes

AnyRef, Any

Type Members

sealed abstract class Attempt[+A] extends Product with Serializable

Right biased Either[Err, A].
trait Codec[A] extends GenCodec[A, A]

Supports encoding a value of type A to a BitVector and decoding a BitVector to a value of A.
type CodecTransformation = ~>[Codec, Codec]

Universally quantified transformation of a Codec to a Codec.
final case class DecodeResult[+A](value: A, remainder: BitVector) extends Product with Serializable

Result of a decoding operation, which consists of the decoded value and the remaining bits that were not consumed by decoding.
trait Decoder[+A] extends AnyRef

Supports decoding a value of type A from a BitVector.
trait DecoderFunctions extends AnyRef

Provides functions for working with decoders.
trait Encoder[-A] extends AnyRef

Supports encoding a value of type A to a BitVector.
trait EncoderFunctions extends AnyRef

Provides functions for working with encoders.
implicit final class EnrichedCoproductDecoder[C <: Coproduct] extends AnyVal

Provides methods specific to decoders of Shapeless coproducts.
implicit final class EnrichedCoproductEncoder[C <: Coproduct] extends AnyVal

Provides methods specific to encoders of Shapeless coproducts.
implicit final class EnrichedHList[L <: HList] extends AnyVal

Provides additional methods on HLists.
trait Err extends AnyRef

Describes an error.
trait GenCodec[-A, +B] extends Encoder[A] with Decoder[B]

Generalized codec that allows the type to encode to vary from the type to decode.
implicit final class HListCodecEnrichedWithHListSupport[L <: HList] extends AnyVal

Provides common operations on a Codec[HList].
final case class SizeBound(lowerBound: Long, upperBound: Option[Long]) extends Product with Serializable

Bounds the size, in bits, of the binary encoding of a codec -- i.
abstract class Transform[F[_]] extends AnyRef

Typeclass that describes type constructors that support the exmap operation.
implicit class TransformSyntax[F[_], A] extends AnyRef

Provides method syntax for working with a type constructor that has a Transform typeclass instance.
abstract class Transformer[A, B] extends AnyRef

Witness operation that supports transforming an F[A] to an F[B] for all F which have a Transform instance available.
implicit final class Tuple2CodecSupport[A] extends AnyVal
implicit final class ValueCodecEnrichedWithGenericSupport[A] extends AnyVal

Provides syntax related to generic programming for codecs of any type.
implicit final class ValueCodecEnrichedWithHListSupport[A] extends AnyVal

Provides HList related syntax for codecs of any type.
sealed abstract class DecodingContext[A] extends AnyRef

Provides the ability to sequence decoding operations such that the remainder of an operation is fed in to the input of the next operation.

Value Members

object Attempt extends Serializable

Companion for Attempt.
object BuildInfo extends Product with Serializable

This object was generated by sbt-buildinfo.
object Codec extends EncoderFunctions with DecoderFunctions

Companion for Codec.
object CodecTransformation extends Serializable

Companion for CodecTransformation.
object Decoder extends DecoderFunctions

Companion for Decoder.
object DecodingContext

Provides constructors for DecodingContext.
object Encoder extends EncoderFunctions

Companion for Encoder.
object Err

Companion for Err.
object GenCodec extends EncoderFunctions with DecoderFunctions

Companion for GenCodec.
object SizeBound extends Serializable

Companion for SizeBound.
object Transform

Companion for Transform.
object Transformer

Companion for Transformer.
package codecs

Provides codecs for common types and combinators for building larger codecs.

package scodec

Type Members

sealed abstract class Attempt[+A] extends Product with Serializable

trait Codec[A] extends GenCodec[A, A]

type CodecTransformation = ~>[Codec, Codec]

final case class DecodeResult[+A](value: A, remainder: BitVector) extends Product with Serializable

trait Decoder[+A] extends AnyRef

trait DecoderFunctions extends AnyRef

trait Encoder[-A] extends AnyRef

trait EncoderFunctions extends AnyRef

implicit final class EnrichedCoproductDecoder[C <: Coproduct] extends AnyVal

implicit final class EnrichedCoproductEncoder[C <: Coproduct] extends AnyVal

implicit final class EnrichedHList[L <: HList] extends AnyVal

trait Err extends AnyRef

trait GenCodec[-A, +B] extends Encoder[A] with Decoder[B]

implicit final class HListCodecEnrichedWithHListSupport[L <: HList] extends AnyVal

final case class SizeBound(lowerBound: Long, upperBound: Option[Long]) extends Product with Serializable

abstract class Transform[F[_]] extends AnyRef

implicit class TransformSyntax[F[_], A] extends AnyRef

abstract class Transformer[A, B] extends AnyRef

implicit final class Tuple2CodecSupport[A] extends AnyVal

implicit final class ValueCodecEnrichedWithGenericSupport[A] extends AnyVal

implicit final class ValueCodecEnrichedWithHListSupport[A] extends AnyVal

sealed abstract class DecodingContext[A] extends AnyRef

Value Members

object Attempt extends Serializable

object BuildInfo extends Product with Serializable

object Codec extends EncoderFunctions with DecoderFunctions

object CodecTransformation extends Serializable

object Decoder extends DecoderFunctions

object DecodingContext

object Encoder extends EncoderFunctions

object Err

object GenCodec extends EncoderFunctions with DecoderFunctions

object SizeBound extends Serializable

object Transform

object Transformer

package codecs

Inherited from AnyRef

Inherited from Any

Ungrouped