jam.types.work.item module

Work item types for the JAM protocol.

class jam.types.work.item.ImportSpec(tree_root: ByteArray32, index: U16)

Bases: Codable, JsonSerde

Import specification structure.

tree_root: ByteArray32

index: U16

__init__(tree_root: ByteArray32, index: U16) → None

Initialize the Codable.

Parameters:

• codec – Optional codec to use for encoding/decoding

• enc_sequence – Optional function that returns sequence of fields to encode

static decode_from(buffer: bytes | bytearray | memoryview, offset: int = 0) → Tuple[T, int]

Decode from buffer. Must be implemented by subclasses or added via decorator.

Parameters:

• buffer – Buffer to decode from

• offset – Starting position in buffer

Returns:

• The decoded value

• Number of bytes read

Return type:

Tuple containing

encode_into(buffer: bytearray, offset: int = 0) → int

Encode into provided buffer.

encode_size() → int

Calculate number of bytes needed to encode.

class jam.types.work.item.ExtrinsicSpec(hash: ByteArray32, len: U32)

Bases: Codable, JsonSerde

Extrinsic specification structure.

hash: ByteArray32

len: U32

__init__(hash: ByteArray32, len: U32) → None

Initialize the Codable.

Parameters:

• codec – Optional codec to use for encoding/decoding

• enc_sequence – Optional function that returns sequence of fields to encode

static decode_from(buffer: bytes | bytearray | memoryview, offset: int = 0) → Tuple[T, int]

Decode from buffer. Must be implemented by subclasses or added via decorator.

Parameters:

• buffer – Buffer to decode from

• offset – Starting position in buffer

Returns:

• The decoded value

• Number of bytes read

Return type:

Tuple containing

encode_into(buffer: bytearray, offset: int = 0) → int

Encode into provided buffer.

encode_size() → int

Calculate number of bytes needed to encode.

class jam.types.work.item.ImportSpecs(initial: Sequence[T] = [], codec: Codec[T] | None = None)

Bases: Vector[ImportSpec]

static decode_from(buffer: bytes | bytearray | memoryview, offset: int = 0) → Tuple[Vector[T], int]

Decode from buffer. Must be implemented by subclasses or added via decorator.

Parameters:

• buffer – Buffer to decode from

• offset – Starting position in buffer

Returns:

• The decoded value

• Number of bytes read

Return type:

Tuple containing

class jam.types.work.item.ExtrinsicSpecs(initial: Sequence[T] = [], codec: Codec[T] | None = None)

Bases: Vector[ExtrinsicSpec]

static decode_from(buffer: bytes | bytearray | memoryview, offset: int = 0) → Tuple[Vector[T], int]

Decode from buffer. Must be implemented by subclasses or added via decorator.

Parameters:

• buffer – Buffer to decode from

• offset – Starting position in buffer

Returns:

• The decoded value

• Number of bytes read

Return type:

Tuple containing

class jam.types.work.item.WorkItem(service: U32, code_hash: ByteArray32, payload: Bytes, refine_gas_limit: U64, accumulate_gas_limit: U64, import_segments: ImportSpecs, extrinsic: ExtrinsicSpecs, export_count: U16)

Bases: Codable, JsonSerde

Work item structure.

service: U32

code_hash: ByteArray32

payload: Bytes

refine_gas_limit: U64

accumulate_gas_limit: U64

import_segments: ImportSpecs

extrinsic: ExtrinsicSpecs

export_count: U16

__init__(service: U32, code_hash: ByteArray32, payload: Bytes, refine_gas_limit: U64, accumulate_gas_limit: U64, import_segments: ImportSpecs, extrinsic: ExtrinsicSpecs, export_count: U16) → None

Initialize the Codable.

Parameters:

• codec – Optional codec to use for encoding/decoding

• enc_sequence – Optional function that returns sequence of fields to encode

static decode_from(buffer: bytes | bytearray | memoryview, offset: int = 0) → Tuple[T, int]

Decode from buffer. Must be implemented by subclasses or added via decorator.

Parameters:

• buffer – Buffer to decode from

• offset – Starting position in buffer

Returns:

• The decoded value

• Number of bytes read

Return type:

Tuple containing

encode_into(buffer: bytearray, offset: int = 0) → int

Encode into provided buffer.

encode_size() → int

Calculate number of bytes needed to encode.