ROS 2

BindingsCollection.ROS2 registers server and operation parsers.

using ByteBard.AsyncAPI.Bindings.ROS2;
using ByteBard.AsyncAPI.Models;

var operation = new AsyncApiOperation();
operation.Bindings.Add(new ROS2OperationBinding
{
    Role = "publisher",
    Node = "orders",
    QosPolicies = new ROS2QosPolicies
    {
        Reliability = "reliable",
        History = "keep_last",
        Durability = "transient_local",
        Lifespan = 0,
        Deadline = -1,
        Liveliness = "automatic",
        LeaseDuration = 0,
    },
});

var server = new AsyncApiServer();
server.Bindings.Add(new ROS2ServerBinding
{
    RmwImplementation = "rmw_fastrtps_cpp",
    DomainId = 42,
});

Bindings.Add(binding) stores the binding under its BindingKey (ros2) for either model level.

Server fields are RmwImplementation and nullable DomainId. Operation fields are Role, Node, and QosPolicies: Reliability, History, Durability, and Liveliness are strings; Lifespan, Deadline, and LeaseDuration are nullable integers.

Write

Attach the typed operation binding at the operation level, then serialize the enclosing document:

using ByteBard.AsyncAPI;
using ByteBard.AsyncAPI.Bindings.ROS2;
using ByteBard.AsyncAPI.Models;
using System.Collections.Generic;

var document = new AsyncApiDocument
{
    Info = new AsyncApiInfo { Title = "Camera", Version = "1.0.0" },
    Channels = new Dictionary<string, AsyncApiChannel>
    {
        ["camera"] = new AsyncApiChannel { Address = "camera" },
    },
    Operations = new Dictionary<string, AsyncApiOperation>
    {
        ["publishCamera"] = new AsyncApiOperation
        {
            Action = AsyncApiAction.Send,
            Channel = new AsyncApiChannelReference("#/channels/camera"),
        },
    },
};
document.Operations["publishCamera"].Bindings.Add(new ROS2OperationBinding
{
    Role = "publisher",
    Node = "camera",
    QosPolicies = new ROS2QosPolicies
    {
        Reliability = "reliable",
        History = "keep_last",
        Durability = "transient_local",
        Lifespan = 0,
        Deadline = -1,
        Liveliness = "automatic",
        LeaseDuration = 0,
    },
});

var yaml = document.SerializeAsYaml(AsyncApiVersion.AsyncApi3_0);

Read and use

Continuing from the Write example above, this snippet uses its yaml variable.

using System;
using ByteBard.AsyncAPI;
using ByteBard.AsyncAPI.Bindings;
using ByteBard.AsyncAPI.Bindings.ROS2;
using ByteBard.AsyncAPI.Models;
using ByteBard.AsyncAPI.Readers;

var settings = new AsyncApiReaderSettings { Bindings = BindingsCollection.ROS2 };
var parsed = new AsyncApiStringReader(settings).Read(yaml, out var diagnostics);
if (parsed.Operations["publishCamera"].Bindings.TryGetValue<ROS2OperationBinding>(out var ros2))
{
    Console.WriteLine($"{ros2.Role} on {ros2.Node}, deadline={ros2.QosPolicies.Deadline}");
}

var parsedServer = new AsyncApiStringReader(settings).ReadFragment<AsyncApiServer>("""
    bindings:
      ros2:
        rmwImplementation: rmw_fastrtps_cpp
        domainId: 42
    """, AsyncApiVersion.AsyncApi3_0, out diagnostics);
if (parsedServer.Bindings.TryGetValue<ROS2ServerBinding>(out var ros2Server))
{
    Console.WriteLine($"{ros2Server.RmwImplementation}, domain={ros2Server.DomainId}");
}

The typed lookups return false if their server or operation binding is absent.

The ROS 2 server and operation serializers omit BindingVersion, even when set. These examples target AsyncAPI 3.1.0; AsyncAPI 2.x serialization converts the surrounding document layout. Policy strings and timing values are not validated against the selected RMW implementation. See shared reader/writer setup.