piece

PieceCID (Piece Commitment CID) utilities

Helper functions for working with Filecoin Piece CIDs

Example

import * as Piece from '@filoz/synapse-core/piece'

Type Alias	Description
LegacyPieceCID	LegacyPieceCID - A constrained CID type for Legacy Piece Commitments. This is implemented as a Link type which is made concrete by a CID.
PieceCID	PieceCID - A constrained CID type for Piece Commitments. This is implemented as a Link type which is made concrete by a CID. A PieceCID uses the raw codec (0x55) and the fr32-sha256-trunc254-padbintree multihash function (0x1011) which encodes the base content length (as padding) of the original piece, and the height of the merkle tree used to hash it.

Variable	Description
MAX_UPLOAD_SIZE	Maximum upload size currently supported by PDP servers.

Function	Description
asLegacyPieceCID	Convert a LegacyPieceCID input (string or CID) to a validated CID This function can be used to parse a LegacyPieceCID (CommPv1) or to downgrade a PieceCID (CommPv2) to a LegacyPieceCID.
asPieceCID	Convert a PieceCID input (string or CID) to a validated CID This is the main function to use when accepting PieceCID inputs
calculate	Calculate the PieceCID (Piece Commitment) for a given data blob
calculateFromIterable	Calculate PieceCID from an async iterable of Uint8Array chunks.
createPieceCIDStream	Create a TransformStream that calculates PieceCID while streaming data through it This allows calculating PieceCID without buffering the entire data in memory
downloadAndValidate	Download data from a Response object, validate its PieceCID, and return as Uint8Array
getSize	Extract the raw (unpadded) size from a PieceCIDv2
getSizeFromPieceCID	Extract the raw (unpadded) size from a PieceCIDv2
hexToPieceCID	Convert a hex representation of a PieceCID to a PieceCID object
isPieceCID	Check if a CID is a valid PieceCID
parse	-
uint8ArrayToAsyncIterable	Convert Uint8Array to async iterable with optimal chunk size.