Commands server

Use ICommandServer to implement low-level command protocol handling on the server side. The server publishes COMMAND_LONG and COMMAND_INT packets addressed to its system/component and can send COMMAND_ACK responses to the requester.

Use case

var serverDevice = ServerDevice.Create(
    new MavlinkIdentity(systemId, componentId),
    core,
    builder =>
    {
        builder.RegisterCommand();
    });

Then get the service:

var commandServer = serverDevice.GetCommand();

Basic handling example:

using var onLong = commandServer.OnCommandLong.SubscribeAwait(async (req, ct) =>
{
    await commandServer.SendCommandAck(
        req.Payload.Command,
        new DeviceIdentity(req.SystemId, req.ComponentId),
        CommandResult.Accepted,
        ct
    );
});

using var onInt = commandServer.OnCommandInt.SubscribeAwait(async (req, ct) =>
{
    await commandServer.SendCommandAck(
        req.Payload.Command,
        new DeviceIdentity(req.SystemId, req.ComponentId),
        CommandResult.Accepted,
        ct
    );
});

Here we are using CommandResult to send a response.

API

ICommandServer

Represents a command server that receives and sends commands.

Property	Type	Description
`OnCommandLong`	`Observable<CommandLongPacket>`	Gets the event stream for receiving `CommandLong` packets.
`OnCommandInt`	`Observable<CommandIntPacket>`	Gets an observable sequence of `CommandIntPacket` events.

Method	Return Type	Description
`SendCommandAck(MavCmd cmd, DeviceIdentity responseTarget, CommandResult result, CancellationToken cancel = default)`	`ValueTask`	Sends a command acknowledgement with the specified parameters.

`ICommandServer.SendCommandAck`

Parameter	Type	Description
`cmd`	`MavCmd`	The command being acknowledged.
`responseTarget`	`DeviceIdentity`	The target device identity for the acknowledgement.
`result`	`CommandResult`	The result of the command execution.
`cancel`	`CancellationToken`	Optional cancellation token.

DeviceIdentity

Represents the identity of a device.

Constructor	Description
`DeviceIdentity()`	Represents a device identity.
`DeviceIdentity(byte systemId, byte componentId)`	Initializes a new instance of the `DeviceIdentity` class.

Property	Type	Description
`Broadcast`	`DeviceIdentity`	Static field representing system `0`, component `0`.
`SystemId`	`byte`	Gets or sets the system ID.
`ComponentId`	`byte`	Gets or sets the unique identifier for the component.

CommandServerHelper

Helper class containing extension methods for ICommandServer interface.

Despite their name, both SendCommandAckAccepted overloads use the MavResult supplied by the caller; they are not limited to MavResultAccepted.

Method	Return Type	Description
`SendCommandAckAccepted(this ICommandServer server, CommandIntPacket req, MavResult result, CancellationToken cancel = default)`	`ValueTask`	Sends an acknowledgement for a `COMMAND_INT` request using the supplied result.
`SendCommandAckAccepted(this ICommandServer server, CommandLongPacket req, MavResult result, CancellationToken cancel = default)`	`ValueTask`	Sends an acknowledgement for a `COMMAND_LONG` request using the supplied result.

`ICommandServer.SendCommandAckAccepted` (`CommandIntPacket` overload)

Parameter	Type	Description
`server`	`ICommandServer`	The command server.
`req`	`CommandIntPacket`	The command request packet.
`result`	`MavResult`	The mav result.
`cancel`	`CancellationToken`	Optional cancel token argument.

`ICommandServer.SendCommandAckAccepted` (`CommandLongPacket` overload)

Parameter	Type	Description
`server`	`ICommandServer`	The command server.
`req`	`CommandLongPacket`	The command long packet.
`result`	`MavResult`	The result of the command.
`cancel`	`CancellationToken`	Optional cancel token argument.

CommandHelper

Provides helper methods for registering and accessing command-related microservices, including base command server and extended CommandLong/CommandInt handlers.

Property	Type	Description
`MicroserviceTypeName`	`string`	Microservice type identifier (`COMMAND`).

Method	Return Type	Description
`RegisterCommand(this IServerDeviceBuilder builder)`	`IServerDeviceBuilder`	Registers `CommandServer` at device builder with default parameters.
`RegisterCommandLongEx(this IServerDeviceBuilder builder)`	`IServerDeviceBuilder`	Registers `CommandLongServerEx` at device builder with default parameters.
`RegisterCommandIntEx(this IServerDeviceBuilder builder)`	`IServerDeviceBuilder`	Registers `CommandIntServerEx` at device builder with default parameters.
`GetCommand(this IServerDevice factory)`	`ICommandServer`	Resolves `ICommandServer` instance from the server device factory.
`GetCommandIntEx(this IServerDevice factory)`	`ICommandServerEx<CommandIntPacket>`	Resolves `ICommandServerEx<CommandIntPacket>` instance from the server device factory.
`GetCommandLongEx(this IServerDevice factory)`	`ICommandServerEx<CommandLongPacket>`	Resolves `ICommandServerEx<CommandLongPacket>` instance from the server device factory.

Last modified: 16 July 2026