Class CommandWorker<TInput, TOutput, TCommand>

Namespace

Virtufin.Worker.DevKit

Assembly

Virtufin.Worker.DevKit.dll

Generic command-dispatching worker. Builds on WorkerBase<TInput, TOutput>: the base class handles codec decode/encode and envelope construction; this class adds strongly-typed command-string extraction and enum dispatch.

Format-agnostic: this class makes no assumption about payload format. The 2-type-param convenience CommandWorker<T> pre-bakes the JsonCloudEventCodec; workers using non-JSON payloads extend the 3-type-param form directly and supply their own codec.

public abstract class CommandWorker<TInput, TOutput, TCommand> : WorkerBase<TInput, TOutput>, IWorker where TCommand : struct, Enum

Type Parameters

TInput

Codec-decoded input payload type.

TOutput

Codec-encoded output payload type.

TCommand

Enum whose identifier names are the wire-level command names (e.g. WebSocketManagerCommand.create for the wire string "create").

Inheritance

object

WorkerBase<TInput, TOutput>

CommandWorker<TInput, TOutput, TCommand>

Implements

IWorker

Derived

CommandWorker<T>

Inherited Members

WorkerBase<TInput, TOutput>.CorrelationIdAttribute

WorkerBase<TInput, TOutput>.ReplyTopicAttribute

WorkerBase<TInput, TOutput>.PublishTopicAttribute

WorkerBase<TInput, TOutput>.FieldError

WorkerBase<TInput, TOutput>.Names

WorkerBase<TInput, TOutput>.ProcessAsync(CloudEvent)

WorkerBase<TInput, TOutput>.ProcessAsync(CloudEvent, TInput)

WorkerBase<TInput, TOutput>.BuildEnvelope(CloudEvent, TOutput)

WorkerBase<TInput, TOutput>.BuildResponse(CloudEvent, TOutput, string, string, IReadOnlyDictionary<string, string>)

WorkerBase<TInput, TOutput>.BuildResponse(CloudEvent, object, string, string, string, IReadOnlyDictionary<string, string>)

WorkerBase<TInput, TOutput>.Error(CloudEvent, string)

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Constructors

CommandWorker(string, ICloudEventCodec<TInput, TOutput>)

A command worker of type workerType, named by the naming library (see WorkerTypeNames).

protected CommandWorker(string workerType, ICloudEventCodec<TInput, TOutput> codec)

Parameters

workerType string

codec ICloudEventCodec<TInput, TOutput>

CommandWorker(Uri, string, ICloudEventCodec<TInput, TOutput>)

protected CommandWorker(Uri source, string responseEventType, ICloudEventCodec<TInput, TOutput> codec)

Parameters

source Uri

responseEventType string

codec ICloudEventCodec<TInput, TOutput>

Fields

FieldCommand

Field name of the command string in the typed input payload.

public const string FieldCommand = "command"

Field Value

string

Methods

ErrorPayload(string)

Build a typed error payload. The base class ProcessAsync(CloudEvent) encodes this via the codec and wraps it in a response CloudEvent (with correlationid, timestamp, etc.).

protected virtual TOutput? ErrorPayload(string message)

Parameters

message string

Returns

TOutput

Remarks

Subclasses override this if the codec has a non-trivial error representation (e.g. a dedicated error type).

ExtractCommand(TInput)

Subclasses override to extract the command string from the typed input payload. Default: not implemented. Override must read the payload in a payload-format-specific way (JSON: node["command"], Protobuf: dedicated field, etc.).

protected abstract string? ExtractCommand(TInput payload)

Parameters

payload TInput

Returns

string

HandleCommandAsync(CloudEvent, TCommand, TInput)

Subclasses override to implement command-specific worker logic. Receives the decoded TInput payload and the parsed command value.

protected abstract Task<TOutput?> HandleCommandAsync(CloudEvent input, TCommand command, TInput payload)

Parameters

input CloudEvent

command TCommand

payload TInput

Returns

Task<TOutput>

ProcessAsync(CloudEvent, TInput)

Sealed dispatch: extract the command string from the typed input, parse the enum, call HandleCommandAsync(CloudEvent, TCommand, TInput). Returns a typed error payload (encoded by the codec) on missing/unknown command.

protected override sealed Task<TOutput?> ProcessAsync(CloudEvent input, TInput payload)

Parameters

input CloudEvent

payload TInput

Returns

Task<TOutput>