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Vyral.Execution.AzureDurable.Functions

Vyral.Execution.AzureDurable.Functions is the optional Microsoft Durable Task bridge for the SDK-neutral Vyral.Execution.AzureDurable package. It keeps the replayed orchestrator free of status-store I/O and handler execution: it calls one start activity and one persisted step activity instead.

A Functions application owns trigger attributes, HTTP authentication, dependency injection, registered Vyral handlers, task-hub settings, and deployment topology. Its function methods call:

// HTTP trigger: receive DurableTaskClient and start through the scheduler bridge.
var client = AzureDurableFunctionsBridge.CreateClient(vyralHost, durableTaskClient);
var run = await client.StartRunAsync(command, cancellationToken);


// Orchestrator trigger: receive TaskOrchestrationContext and command input.
return await AzureDurableFunctionsBridge.OrchestrateAsync(vyralHost, context, command);


// Start and step activity triggers respectively:
return await AzureDurableFunctionsBridge.StartActivityAsync(vyralHost, command);
return await AzureDurableFunctionsBridge.StepActivityAsync(vyralHost, command);

The bridge supports the portable durable.waits capability. A handler-side timer or external-event wait registers its Vyral state in the step activity and suspends that activity. The replayed orchestrator then uses CreateTimer or WaitForExternalEvent; its next step activity atomically persists the wake outcome before rerunning the handler. Handlers must checkpoint non-idempotent work before waiting, since the handler body is replayed from its beginning after a wake.

Starting is resilient to the small gap between reserving a Vyral run and submitting its provider orchestration. An idempotent replay of an active run calls the scheduler again. The Functions scheduler deduplicates Durable instances in Pending and Running states, so a confirmed or ambiguous prior submission remains one orchestration while an earlier failed submission is retried.

Canonical source: src/Vyral.Execution.AzureDurable.Functions/README.md at cb04cf7