CoAP.ResourceMvc

CoAP Resource/MVC sample

This sample shows the recommended host-managed CoAP resource model:

builder.Services.AddCoapServer(options =>
{
    options.ListenAnyIP(5683);
});
builder.Services.AddCoapJsonPayloadBinder(ResourceMvcJsonContext.Default);
builder.Services.AddCoapResources(options =>
{
    options.AddEndpointFactory(MyGeneratedCoapEndpoints.Create);
});

var app = builder.Build();
app.MapCoapResources();
app.Run();

MyGeneratedCoapEndpoints.Create(...) is emitted by the CoAP.NET.SourceGeneration analyzer from the [CoapResource] and method route attributes in Program.cs.

Run it from the repository root:

dotnet run --project CoAP.Example/CoAP.ResourceMvc/CoAP.ResourceMvc.csproj

The sample exposes:

• GET sensors/{sensor}/latest?unit=c: query binding and JSON response.
• POST sensors/{sensor}/readings?point=1&tag=fast: JSON payload binding, Content-Format and Accept binding.
• POST sensors/{sensor}/snapshot: binary payload binding.
• GET/OBSERVE sensors/{sensor}/status: Observe metadata and JSON response.
• GET sensors/{sensor}/fault: explicit error response.
• .well-known/core: CoAP.NET-generated discovery output.

Example C# client calls:

using CoAP;
using System.Text;

var readingClient = new CoapClient(
    new Uri("coap://localhost/sensors/demo/readings?point=1&tag=fast"));
var reading = readingClient.Post(
    "{\"unit\":\"c\",\"value\":21.5}",
    MediaType.ApplicationJson,
    MediaType.ApplicationJson);

var snapshotClient = new CoapClient(new Uri("coap://localhost/sensors/demo/snapshot"));
var snapshot = snapshotClient.Post(
    Encoding.UTF8.GetBytes("raw-bytes"),
    MediaType.ApplicationOctetStream,
    MediaType.ApplicationJson);

var discoveryClient = new CoapClient(new Uri("coap://localhost/.well-known/core"));
var discovery = discoveryClient.Get(MediaType.ApplicationLinkFormat);

Unsupported media negotiation is handled by CoAP.NET before the resource action is invoked. For example, posting text/plain to sensors/demo/readings returns 4.15 Unsupported Content-Format; requesting Accept: text/plain from the same JSON endpoint returns 4.06 Not Acceptable.