Class PollableStepHandler<TInput>

Namespace

FlowOrchestrator.Core.Execution

Assembly

FlowOrchestrator.Core.dll

Base class for step handlers that need to repeatedly query an external system until a condition is met, using Hangfire's delayed scheduling for pacing.

public abstract class PollableStepHandler<TInput> : IStepHandler<TInput> where TInput : IPollableInput

Type Parameters

TInput

Step input type implementing IPollableInput.

Inheritance

object

PollableStepHandler<TInput>

Implements

IStepHandler<TInput>

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Remarks

Subclasses implement FetchAsync(IExecutionContext, IFlowDefinition, IStepInstance<TInput>) to perform the actual fetch. The base class manages:

• Tracking poll start time and attempt count in the step inputs (persisted between reschedules).
• Evaluating PollConditionPath against the response.
• Enforcing PollMinAttempts before accepting a positive condition.
• Returning Pending with DelayNextStep to reschedule.
• Returning Failed on timeout.

Methods

ExecuteAsync(IExecutionContext, IFlowDefinition, IStepInstance<TInput>)

Executes the step with strongly-typed inputs and returns an optional result value.

public ValueTask<object?> ExecuteAsync(IExecutionContext ctx, IFlowDefinition flow, IStepInstance<TInput> step)

Parameters

ctx IExecutionContext

flow IFlowDefinition

The flow definition currently executing.

step IStepInstance<TInput>

The step instance with inputs already deserialised to TInput.

Returns

ValueTask<object>

The step output, or a IStepResult to control execution behaviour.

FetchAsync(IExecutionContext, IFlowDefinition, IStepInstance<TInput>)

Performs the actual data fetch against the external system.

protected abstract ValueTask<(JsonElement Result, bool IsJson)> FetchAsync(IExecutionContext ctx, IFlowDefinition flow, IStepInstance<TInput> step)

Parameters

ctx IExecutionContext

flow IFlowDefinition

step IStepInstance<TInput>

Returns

ValueTask<(JsonElement Result, bool IsJson)>

A tuple of the fetched JsonElement payload and a flag indicating whether the response was parsed as valid JSON (required for PollConditionPath evaluation).