Packages

•  package root

  Definition Classes

  root

•  package com

  Definition Classes

  root

•  package digitalasset

  Definition Classes

  com

•  package canton

  Definition Classes

  digitalasset

•  package ledger

  Definition Classes

  canton

•  package participant

  Definition Classes

  ledger

•  package state

  Definition Classes

  participant

•  package v2

  Interfaces to read from and write to an (abstract) participant state.

  Interfaces to read from and write to an (abstract) participant state.

  A Daml ledger participant is code that allows to actively participate in the evolution of a shared Daml ledger. Each such participant maintains a particular view onto the state of the Daml ledger. We call this view the participant state.

  Actual implementations of a Daml ledger participant will likely maintain more state than what is exposed through the interfaces in this package, which is why we talk about an abstract participant state. It abstracts over the different implementations of Daml ledger participants.

  The interfaces are optimized for easy implementation. The v2.WriteService interface contains the methods for changing the participant state (and potentially the state of the Daml ledger), which all ledger participants must support. These methods are for example exposed via the Daml Ledger API. Actual ledger participant implementations likely support more implementation-specific methods. They are however not exposed via the Daml Ledger API. The v2.ReadService interface contains the one method v2.ReadService.stateUpdates to read the state of a ledger participant. It represents the participant state as a stream of v2.Updates to an initial participant state. The typical consumer of this method is a class that subscribes to this stream of v2.Updates and reconstructs (a view of) the actual participant state. See the comments on v2.Update and v2.ReadService.stateUpdates for details about the kind of updates and the guarantees given to consumers of the stream of v2.Updates.

  We do expect the interfaces provided in com.digitalasset.canton.ledger.participant.state to evolve, which is why we provide them all in the com.digitalasset.canton.ledger.participant.state.v2 package. Where possible we will evolve them in a backwards compatible fashion, so that a simple recompile suffices to upgrade to a new version. Where that is not possible, we plan to introduce new version of this API in a separate package and maintain it side-by-side with the existing version if possible. There can therefore potentially be multiple versions of participant state APIs at the same time. We plan to deprecate and drop old versions on separate and appropriate timelines.

  Definition Classes

  state

•  object ReadService

  Definition Classes

  v2

• ConnectedDomainRequest
• ConnectedDomainResponse

com.digitalasset.canton.ledger.participant.state.v2.ReadService

ConnectedDomainRequest