AzureFunctions.TestFramework.Dapr 0.13.2

AzureFunctions.TestFramework.Dapr

Dapr Trigger, Input, and Output binding support for the Azure Functions Test Framework.

Installation

dotnet add package AzureFunctions.TestFramework.Dapr

Supported bindings

Note: The Dapr extension is supported in Kubernetes, Azure Container Apps, Azure IoT Edge, and other self-hosted modes only. It is not available in the Azure Functions Consumption plan.

DaprBindingTrigger

Use InvokeDaprBindingAsync to simulate a Dapr input binding event trigger.

var result = await host.InvokeDaprBindingAsync(
    "ProcessDaprBinding",
    data: "my-event-data");

Assert.True(result.Success);

Pass a POCO to have it serialized to JSON automatically:

var payload = new MyEvent { Id = "evt-1", Message = "hello" };

var result = await host.InvokeDaprBindingAsync(
    "ProcessDaprBinding",
    data: payload);

Assert.True(result.Success);

Function example

[Function("ProcessDaprBinding")]
public void Run(
    [DaprBindingTrigger(BindingName = "my-binding")] string data)
{
    _logger.LogInformation("Received Dapr binding event: {Data}", data);
}

DaprServiceInvocationTrigger

Use InvokeDaprServiceInvocationAsync to simulate a Dapr service invocation call.

var result = await host.InvokeDaprServiceInvocationAsync(
    "HandleInvocation",
    body: "request-body");

Assert.True(result.Success);

Pass a POCO to have it serialized to JSON automatically:

var request = new MyRequest { OrderId = "ord-42" };

var result = await host.InvokeDaprServiceInvocationAsync(
    "HandleInvocation",
    body: request);

Assert.True(result.Success);

Function example

[Function("HandleInvocation")]
public void Run(
    [DaprServiceInvocationTrigger] string body)
{
    _logger.LogInformation("Dapr service invocation: {Body}", body);
}

DaprTopicTrigger

Use InvokeDaprTopicAsync to simulate a Dapr pub/sub topic message trigger.

var result = await host.InvokeDaprTopicAsync(
    "ProcessTopicMessage",
    message: "hello from dapr pub/sub");

Assert.True(result.Success);

Pass a POCO to have it serialized to JSON automatically:

var order = new Order { Id = "ord-1", Amount = 99.99m };

var result = await host.InvokeDaprTopicAsync(
    "ProcessTopicMessage",
    message: order);

Assert.True(result.Success);

Function example

[Function("ProcessTopicMessage")]
public void Run(
    [DaprTopicTrigger("my-pubsub", Topic = "orders")] string message)
{
    _logger.LogInformation("Received Dapr topic message: {Message}", message);
}

Output bindings

Output bindings are captured automatically via FunctionInvocationResult when the worker SDK correctly marks them as output bindings.

Note: Due to a known bug in the Dapr extension's source generator (v1.0.1), properties decorated with Dapr output binding attributes (e.g. [DaprPublishOutput], [DaprStateOutput], etc.) on POCO return types are generated with direction: "In" instead of direction: "Out". As a result, the worker SDK does not populate InvocationResponse.OutputData for these properties and FunctionInvocationResult.OutputData will be empty. Functions with Dapr output bindings still execute successfully.

Dapr input binding limitations

Note: The Azure Functions Worker SDK source generator (as of v2.0.7) does not emit binding metadata for [DaprStateInput] or [DaprSecretInput] parameters. Because of this, the WithDaprStateInput and WithDaprSecretInput builder extensions have no effect in source-generated mode.

To work with [DaprStateInput] or [DaprSecretInput] in integration tests, override the Dapr HTTP client in DI to return a fake response from the Dapr sidecar endpoint:

var host = await new FunctionsTestHostBuilder()
    .WithFunctionsAssembly(typeof(MyFunction).Assembly)
    .WithHostBuilderFactory(Program.CreateHostBuilder)
    .ConfigureServices(services =>
    {
        // Replace the Dapr HTTP client to return a fake state value
        services.AddHttpClient("dapr-client", client => { ... });
    })
    .BuildAndStartAsync();

When the source generator is updated to emit daprState and daprSecret binding metadata, the WithDaprStateInput and WithDaprSecretInput extensions will work automatically without any additional configuration.

Testing across all four flavours

Add the Dapr package reference to your test project and all four function-app test flavours:

<PackageReference Include="AzureFunctions.TestFramework.Dapr" />

See the 4-flavour matrix test pattern for the concrete test class structure.