Command

Overview

Conform to the Command protocol to provide the logic for the Formic engine to invoke a command effecting a remote host or service.

The engine calls run(host:logger:) to invoke the command, providing a Host instance that presents the host to the logic for executing the command. The engine may provide a Logger instance, to allow the command to log messages, typically to the console when invoked from a command-line interface. Log output at debug or trace log levels within your command. Throw errors to indicate unavoidable error conditions, and report failure conditions by including the relevant information into CommandOutput that you return from this method.

Inspecting Commands

• var id: UUID

  The identifier of a command.

• var ignoreFailure: Bool

  A Boolean value that indicates whether a failing command within a sequence should fail the overall sequence of commands.

• var retry: Backoff

  The retry settings to apply when a command fails.

• var executionTimeout: Duration

  The maximum time allowed for the command to execute.

• struct Backoff

  The retry and backoff delay settings for a command.

Invoking Commands

• func run(host: RemoteHost, logger: Logger?) async throws -> CommandOutput

  The function that is invoked by an engine to run the command.