Safe Haskell	None
Language	Haskell2010

Ouroboros.Consensus.Util.CBOR

Contents

Incremental parsing in I/O
Higher-level incremental interface
Decode as FlatTerm
HasFS interaction
Encoding/decoding containers

Synopsis

data IDecodeIO a
- = Partial (Maybe ByteString → IO (IDecodeIO a))
- | Done !ByteString !ByteOffset a
- | Fail !ByteString !ByteOffset DeserialiseFailure
deserialiseIncrementalIO ∷ (∀ s. Decoder s a) → IO (IDecodeIO a)
fromIDecode ∷ IDecode RealWorld a → IDecodeIO a
data Decoder m = Decoder {
- decodeNext ∷ ∀ a. (∀ s. Decoder s a) → m a
}
initDecoderIO ∷ IO ByteString → IO (Decoder IO)
decodeAsFlatTerm ∷ ByteString → Either DeserialiseFailure FlatTerm
data ReadIncrementalErr
- = ReadFailed DeserialiseFailure
- | TrailingBytes ByteString
readIncremental ∷ ∀ m a. IOLike m ⇒ SomeHasFS m → (∀ s. Decoder s a) → FsPath → m (Either ReadIncrementalErr a)
withStreamIncrementalOffsets ∷ ∀ m h a r. (IOLike m, HasCallStack) ⇒ HasFS m h → (∀ s. Decoder s (ByteString → a)) → FsPath → (Stream (Of (Word64, (Word64, a))) m (Maybe (ReadIncrementalErr, Word64)) → m r) → m r
decodeList ∷ Decoder s a → Decoder s [a]
decodeMaybe ∷ Decoder s a → Decoder s (Maybe a)
decodeSeq ∷ Decoder s a → Decoder s (StrictSeq a)
decodeWithOrigin ∷ Decoder s a → Decoder s (WithOrigin a)
encodeList ∷ (a → Encoding) → [a] → Encoding
encodeMaybe ∷ (a → Encoding) → Maybe a → Encoding
encodeSeq ∷ (a → Encoding) → StrictSeq a → Encoding
encodeWithOrigin ∷ (a → Encoding) → WithOrigin a → Encoding

Incremental parsing in I/O

data IDecodeIO a Source #

Constructors

Partial (Maybe ByteString → IO (IDecodeIO a))
Done !ByteString !ByteOffset a
Fail !ByteString !ByteOffset DeserialiseFailure

deserialiseIncrementalIO ∷ (∀ s. Decoder s a) → IO (IDecodeIO a) Source #

fromIDecode ∷ IDecode RealWorld a → IDecodeIO a Source #

Higher-level incremental interface

data Decoder m Source #

Constructors

Decoder
Fields decodeNext ∷ ∀ a. (∀ s. Decoder s a) → m a Decode next failure May throw `DeserialiseFailure`

initDecoderIO ∷ IO ByteString → IO (Decoder IO) Source #

Construct incremental decoder given a way to get chunks

Resulting decoder is not thread safe.

Decode as FlatTerm

decodeAsFlatTerm ∷ ByteString → Either DeserialiseFailure FlatTerm Source #

HasFS interaction

data ReadIncrementalErr Source #

Constructors

ReadFailed DeserialiseFailure	Could not deserialise the data
TrailingBytes ByteString	Deserialisation was successful, but there was additional data

Instances

Instances details

Eq ReadIncrementalErr Source #
Instance details Defined in Ouroboros.Consensus.Util.CBOR Methods (==) ∷ ReadIncrementalErr → ReadIncrementalErr → Bool Source # (/=) ∷ ReadIncrementalErr → ReadIncrementalErr → Bool Source #
Show ReadIncrementalErr Source #
Instance details Defined in Ouroboros.Consensus.Util.CBOR Methods showsPrec ∷ Int → ReadIncrementalErr → ShowS Source # show ∷ ReadIncrementalErr → String Source # showList ∷ [ReadIncrementalErr] → ShowS Source #

readIncremental ∷ ∀ m a. IOLike m ⇒ SomeHasFS m → (∀ s. Decoder s a) → FsPath → m (Either ReadIncrementalErr a) Source #

Read a file incrementally

NOTE: The MonadThrow constraint is only needed for bracket. This function does not actually throw anything.

NOTE: This uses a chunk size of roughly 32k. If we use this function to read small things this might not be ideal.

NOTE: This currently expects the file to contain precisely one value; see also withStreamIncrementalOffsets.

withStreamIncrementalOffsets ∷ ∀ m h a r. (IOLike m, HasCallStack) ⇒ HasFS m h → (∀ s. Decoder s (ByteString → a)) → FsPath → (Stream (Of (Word64, (Word64, a))) m (Maybe (ReadIncrementalErr, Word64)) → m r) → m r Source #

Read multiple as incrementally from a file in a streaming way.

Continuation-passing style to ensure proper closure of the file.

Reads the offset (Word64) of the start of each a, the size (Word64) of each a, and each a itself. When deserialising fails, it passes all already deserialised as, the error, and the offset after which the failure occurred.

NOTE: f we introduce user-facing streaming API also, the fact that we are using streaming here should not dictate that we should stick with it later; rather, we should revisit this code at that point.

Encoding/decoding containers

decodeList ∷ Decoder s a → Decoder s [a] Source #

decodeMaybe ∷ Decoder s a → Decoder s (Maybe a) #

decodeSeq ∷ Decoder s a → Decoder s (StrictSeq a) Source #

decodeWithOrigin ∷ Decoder s a → Decoder s (WithOrigin a) Source #

encodeList ∷ (a → Encoding) → [a] → Encoding Source #

encodeMaybe ∷ (a → Encoding) → Maybe a → Encoding #

encodeSeq ∷ (a → Encoding) → StrictSeq a → Encoding Source #

encodeWithOrigin ∷ (a → Encoding) → WithOrigin a → Encoding Source #