ProtoTest.Devices 1.1.2

ProtoTest.Devices

Preview: the surface can change before 1.2.

Talk to devices - simulators or hardware - from the same test context, lifecycle and trace. A suite declares a named device client once and gets typed device instances per test by id.

dotnet add package ProtoTest.Devices
dotnet add package ProtoTest.Devices.WebSocket              # ws:// and wss:// endpoints
dotnet add package ProtoTest.Devices.WebSocket.AspNetCore   # in-process endpoints, no socket
dotnet add package ProtoTest.Devices.Mqtt                   # MQTT publish/subscribe
dotnet add package ProtoTest.Devices.Mqtt.Testcontainers  # a Mosquitto broker owned by the run
dotnet add package ProtoTest.Devices.Tcp                    # raw TCP, connecting out or listening
dotnet add package ProtoTest.Devices.Serial                 # COM ports and /dev/tty lines

Includes

• Named device clients declared once, mirroring the REST and GraphQL builders: devices.AddWebSocketClient("Chargers", path: "/ocpp/{deviceId}").AddDevice<AcCharger>() or devices.AddMqttClient("Meters", "meters/{deviceId}/out", "meters/{deviceId}/in").AddDevice<FlowMeter>().
• Typed device classes: derive from ProtoDevice, add domain methods, and compose the protected ConnectAsync, SendAsync, ReceiveAsync and ExpectAsync primitives.
• Per-test instances through Proto.Context.Devices("Chargers").For<AcCharger>("CP-001"), released with the test.
• Addresses resolve per test: an explicit template ({deviceId} filled in), a resolver, or the application's address when the client is registered inside AddApplication.
• Per-client transport settings through WithSetting, filled per device ({deviceId} included) and read by the transport through DeviceEndpoint.Setting; a credential belongs here, not in the traced address.
• Trace operations (device.connect/send/receive/command) and a device entity with client, type, transport, address and connection state; the release path disconnects the device and records it.
• Assertion-level coverage: a matched expectation records its message kind, and the client's protocol catalog reports kinds no test asserted as gaps.
• Stream framing for TCP, serial and custom stream transports: DeviceFramers.Lines, Delimited, Enveloped, LengthPrefixed and FixedLength, set per client with WithFramer, and StreamDeviceConnection for a stream of your own.
• Device messages as records: text (DeviceMessage.Format/Parse, prefix, separator or fixed widths) or binary ([DeviceBinaryMessage], ToBytes/FromBytes), with [DeviceChecksum<T>] (NMEA, CRC-16/Modbus, XOR, sum) and [DeviceFormat<T>] field formatters (DeviceFormatters: scaled, hex, Unix time, BCD). SendMessageAsync/ExpectMessageAsync on the device, and DeviceMessageProtocol for coverage per message type.
• ListenAsync for transports the system under test connects to, such as AddTcpListener.
• [RequiresDevice<TDevice>] skips tests the environment cannot run.

Limits

• One instance per (client, type, id) per test; devices are not shared across tests.
• One conversation per device instance: connect is single-flight, sends are serialized, one receive is in flight at a time, and a send racing a disconnect fails with a device error naming the device.
• An in-process endpoint needs ProtoTest.Devices.WebSocket.AspNetCore; the socket transport reaches published addresses. A client is only routed through its own application's in-process transport.
• ExpectAsync consumes frames; the bounded exchange log is for failure messages.

Learn more

• Devices
• Test time