Missions server

Use IMissionServer to implement low-level mission protocol handling on the server side (autopilot/simulator).

First register the service:

var serverDevice = ServerDevice.Create(
    new MavlinkIdentity(config.SystemId, config.ComponentId),
    core,
    builder =>
    {
        // register other services...
        builder.RegisterMission();
    });

Then get the service:

var missionServer = serverDevice.GetMission();

Typical handling example:

var items = new List<ServerMissionItem>();

using var onList = missionServer.OnMissionRequestList.SubscribeAwait(async (req, ct) =>
{
    await missionServer.SendMissionCount((ushort)items.Count, req.SystemId, req.ComponentId);
});

using var onItem = missionServer.OnMissionRequestInt.SubscribeAwait(async (req, ct) =>
{
    if (req.Payload.Seq >= items.Count)
    {
        await missionServer.SendMissionAck(MavMissionResult.MavMissionInvalid, req.SystemId, req.ComponentId);
        return;
    }

    await missionServer.SendMissionItemInt(items[req.Payload.Seq], req.SystemId, req.ComponentId, ct);
});

using var onClear = missionServer.OnMissionClearAll.SubscribeAwait(async (req, ct) =>
{
    items.Clear();
    await missionServer.SendMissionAck(MavMissionResult.MavMissionAccepted, req.SystemId, req.ComponentId);
});

IMissionServer

Property	Type	Description
`OnMissionCount`	`Observable<MissionCountPacket>`	Event that is raised whenever the mission count is updated..
`OnMissionRequestList`	`Observable<MissionRequestListPacket>`	Gets an observable sequence of MissionRequestListPacket that represents the event raised when a mission request list is received.
`OnMissionRequestInt`	`Observable<MissionRequestIntPacket>`	Gets an observable sequence of for mission requests of type int.
`OnMissionClearAll`	`Observable<MissionClearAllPacket>`	Gets an observable sequence of MissionClearAllPacket events.
`OnMissionSetCurrent`	`Observable<MissionSetCurrentPacket>`	Represents an event that is raised when a mission is set as the current mission.
`OnMissionAck`	`Observable<MissionAckPayload>`	Gets the observable sequence that emits MissionAckPayload when a mission acknowledgement is received.

Method	Return Type	Description
`SendMissionAck(MavMissionResult result, byte targetSystemId = 0, byte targetComponentId = 0, MavMissionType? type = null)`	`ValueTask`	Sends a mission acknowledgment message to the specified target system and component IDs.
`SendMissionCount(ushort count, byte targetSystemId = 0, byte targetComponentId = 0)`	`ValueTask`	Sends the mission count to the specified target system and component IDs.
`SendReached(ushort seq, CancellationToken cancel = default)`	`ValueTask`	Sends the reached value of a sequence.
`SendMissionCurrent(ushort current, CancellationToken cancel = default)`	`ValueTask`	Sends the current mission index to the system.
`SendMissionItemInt(ServerMissionItem item, byte targetSystemId = 0, byte targetComponentId = 0, CancellationToken cancel = default)`	`ValueTask`	Sends a mission item to the server.
`RequestMissionItem(ushort index, MavMissionType type, byte targetSystemId = 0, byte targetComponentId = 0, CancellationToken cancel = default)`	`Task<ServerMissionItem>`	Requests a mission item from the server.

`IMissionServer.SendMissionAck`

Parameter	Type	Description
`result`	`MavMissionResult`	The result of the mission.
`targetSystemId`	`byte`	The target system ID. Default value is 0.
`targetComponentId`	`byte`	The target component ID. Default value is 0.
`type`	`MavMissionType?`	The mission type. Default value is null.

`IMissionServer.SendMissionCount`

Parameter	Type	Description
`count`	`ushort`	The number of missions to be sent.
`targetSystemId`	`byte`	The ID of the target system. (optional, default value is 0)
`targetComponentId`	`byte`	The ID of the target component. (optional, default value is 0)

`IMissionServer.SendReached`

Parameter	Type	Description
`seq`	`ushort`	The sequence number.
`cancel`	`CancellationToken`	Optional cancel token argument.

`IMissionServer.SendMissionCurrent`

Parameter	Type	Description
`current`	`ushort`	Sends the current mission index to the system.
`cancel`	`CancellationToken`	Optional cancel token argument.

`IMissionServer.SendMissionItemInt`

Parameter	Type	Description
`item`	`ServerMissionItem`	The mission item to be sent.
`targetSystemId`	`byte`	The target system ID. Default value is 0.
`targetComponentId`	`byte`	The target component ID. Default value is 0.
`cancel`	`CancellationToken`	Optional cancel token argument.

`IMissionServer.RequestMissionItem`

Parameter	Type	Description
`index`	`ushort`	The index of the mission item to request.
`type`	`MavMissionType`	The type of the mission item.
`targetSystemId`	`byte`	The target system ID. Default value is 0.
`targetComponentId`	`byte`	The target component ID. Default value is 0.
`cancel`	`CancellationToken`	Optional cancel token argument.

Last modified: 18 February 2026