Module client

Substrate Client and associated logic.

The Client is one of the most important components of Substrate. It mainly comprises two parts:

• A database containing the blocks and chain state, generally referred to as the Backend.
• A runtime environment, generally referred to as the Executor.

Initialization

Creating a Client is done by calling the new method and passing to it a Backend and an Executor.

The former is typically provided by the sc-client-db crate.

The latter typically requires passing one of:

• A LocalCallExecutor running the runtime locally.
• A RemoteCallExecutor that will ask a third-party to perform the executions.
• A RemoteOrLocalCallExecutor combination of the two.

Additionally, the fourth generic parameter of the Client is a marker type representing the ways in which the runtime can interface with the outside. Any code that builds a Client is responsible for putting the right marker.

Structs

Client

Substrate Client

ClientConfig

Client configuration items.

LocalCallExecutor

Call executor that executes methods locally, querying all required data from local backend.

Functions

new_with_backend

Create a client with the explicitly provided backend. This is useful for testing backend implementations.