Crate jam_types

JAM types used within the PVM instances (service code and authorizer code).

Macros

chain_params

Structs

AccumulateItem

The result and surrounding context of a single Refinement operation passed in to the Accumulation logic.

AuthOutput

Output data of Is Authorized operation, passed into both Refinement and Accumulation.

AuthParam

Authorization parameter.

AuthQueueLen

Number of authorizations in a queue allocated to a core.

Authorization

Data constituting the Authorization Token in a Work Package.

Authorizer

The authorizer tuple which together identifies a means of determining whether a Work Package is acceptable to execute on a core.

AuthorizerHash

Hash of an encoded Authorizer value.

CodeHash

Hash of PVM program code.

ExtrinsicHash

Hash of a piece of extrinsic data.

ExtrinsicSpec

Specification of a single piece of extrinsic data.

FixedVec

Vector type with a fixed length.

HeaderHash

Hash of an encoded block header.

ImportSpec

Import segments specification, which identifies a single exported segment.

InvokeArgs

Args for invoking an inner PVM.

MaxImports

Maximum number of imports in a Work Package.

MaxWorkItems

Maximum number of Work Items in a Work Package.

Memo

Transfer memo data, included with balance transfers between services.

OpaqueBandersnatchPublic

Plain-old-data struct of the same length as an encoded Bandersnatch public key.

OpaqueEd25519Public

Plain-old-data struct of the same length as an encoded Ed25519 public key.

OpaqueValKeyset

Plain-old-data struct of the same length and layout to ValKeyset struct. This does not bring in any cryptography.

OpaqueValidatorMetadata

Additional information on a validator, opaque to the actual usage.

Parameters

Baseline parameters for the JAM protocol.

PayloadHash

Hash of a Work Item’s WorkPayload.

RefineContext

Various pieces of information helpful to contextualize the Refinement process.

SegmentHash

Hash of a Segment value.

SegmentLen

Number of bytes in a segment. This is fixed.

SegmentSliceLen

Returns the number of bytes in a segment slice.

SegmentTreeRoot

Hash of a segment tree root node.

ServiceInfo

Information concerning a particular service’s state.

TransferRecord

A single deferred transfer of balance and/or data, passed in to the invocation of On Transfer.

ValCount

Total number of validators in the JAM.

VecMap

An mapping of key/value pairs stored as pairs ordered by their key in a Vec.

VecSet

An set of items stored in order in a Vec.

WorkItem

A definition of work to be done by the Refinement logic of a service and transformed into a WorkOutput for its Accumulation logic.

WorkOutput

Output data of Refinement operation, passed into Accumulation.

WorkPackage

A work-package, a collection of work-items together with authorization and contextual information. This is processed in-core with Is-Authorized and Refine logic to produce a work-report.

WorkPackageHash

Hash of an encoded Work Package.

WorkPayload

Payload data defining a Work Item.

Enums

RootIdentifier

Reference to a sequence of import segments, which when combined with an index forms a commitment to a specific segment of data.

Constants

JAM_COMMON_ERA

Beginning of the Jam “Common Era” (1200 UTC on January 1, 2025), as seconds after the Unix epoch.

MEMO_LEN

Length of a transfer memo in bytes.

POINT_LEN

Number of bytes in an erasure-coding point.

SEGMENT_LEN

Number of bytes in a segment. This is fixed.

Traits

BoundedMap

Trait for vector types which have a bounded length allowing element-wise transformation.

Get

A trait for querying a single value from a type.

MapLike

A data-structure providing the storage and lookup of key/value pairs with exclusive keys.

SetLike

A data-structure providing the storage of non-duplicated items and the querying of their inclusion.

ToAtomic

Functions

auth_queue_len

Number of authorizations in a queue allocated to a core.

basic_piece_len

Number of bytes in a basic EC piece.

basic_piece_points

Number of points in a piece.

max_dependencies

Maximum number of dependencies (total of prerequisites and SR lookup entries).

max_exports

Maximum number of exports in a Work Package.

max_extrinsics

Maximum number of extrinsics in a Work Package.

max_imports

Maximum number of imports in a Work Package.

max_input

Maximum size of a Work Package together with all extrinsic data and imported segments.

max_work_items

Maximum number of Work Items in a Work Package.

min_turnaround_period

Minimum period in blocks between going from becoming Available to Zombie, and then again from Zombie to non-existent.

pieces_per_segment

Returns the number of pieces in a segment.

segment_len

Number of bytes in a segment. This is fixed.

segment_slice_len

Returns the number of bytes in a segment slice.

val_count

Total number of validators in the JAM.

Type Aliases

AuthQueue

A queue of AuthorizerHashs, each of which will be rotated into the authorizer pool for a core.

Balance

Type to represent a balance.

CoreIndex

Type to represent the index of a compute core.

Hash

A basic 256-bit data value.

OpaqueValKeysets

The opaque keys for each validator.

Segment

A segment of data.

ServiceId

Type to represent the index of a service.

SignedGas

Type to represent some gas which may be below zero. This is used primarily for the invoke hostcall API which must be able to return a negative gas amount in case of a gas overrun.

Slot

Type that represents a time slot of six seconds.

ValIndex

Type to represent the index of a validator.

WorkItemImportsVec

A sequence of import specifications.