azure-functions-dotnet-worker - Bindings does not pass value tuple input parameters

Question

Hello,

Following the official page here, it seems that binding value tuple input parameters does not work when using .net 7 with v4 Azure Functions and the following libs:

<PackageReference Include="Microsoft.Azure.Functions.Extensions" Version="1.1.0" />

<PackageReference Include="Microsoft.Azure.Functions.Worker" Version="1.20.0" />

<PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.DurableTask" Version="1.0.4" />

<PackageReference Include="Microsoft.Azure.Functions.Worker.Sdk" Version="1.15.1" />

<PackageReference Include="Microsoft.DurableTask.Client" Version="1.0.5" />

<PackageReference Include="Microsoft.DurableTask.Worker" Version="1.0.5" />

<PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="8.0.0" />

<PackageReference Include="Microsoft.Extensions.Hosting" Version="8.0.0" />

Could you please investigate this, because I have run exactly the code from the documentation and the values received in the activity function are NULL. Is this not supported anymore? In the documentation it seems that it should be supported.

Thank you!

Answer 1

adriana_malea Thanks for posting your question in Microsoft Q&A. I was able to reproduce this error at my end and see the below findings. Isolated model uses System.Text.Json for serialization and as per discussion: https://github.com/dotnet/runtime/issues/70352 ValueTuples are not serialized by default unless you change options.IncludeFields = true.

So, I added this configuration in Program.cs like below:

services.Configure<JsonSerializerOptions>(o => o.IncludeFields = true);

and tested the below code which worked as expected.

        public record CourseInfo(string Major, int UniversityYear);

        [Function("GetCourseRecommendations")]
        public static async Task<object> RunOrchestrator(
            [OrchestrationTrigger] TaskOrchestrationContext context)
        {           
            CourseInfo courseRecommendations = await context.CallActivityAsync<CourseInfo>(
                "CourseRecommendations", ("ComputerScience", 2009));
            return courseRecommendations;
        }

        [Function("CourseRecommendations")]
        public static async Task<CourseInfo> Mapper(
            [ActivityTrigger] (string Major, int UniversityYear) studentInfo, FunctionContext executionContext)
        {
            CourseInfo courseInfo = new (studentInfo.Major, studentInfo.UniversityYear);
            return courseInfo;   
        }

However, we don't recommend changing the default behavior as this is considered a risky behavior as described in the repo. So, consider using record instead of ValueTuplelike below:

public record CourseInfo(string Major, int UniversityYear);

        [Function("GetCourseRecommendations")]
        public static async Task<object> RunOrchestrator(
            [OrchestrationTrigger] TaskOrchestrationContext context)
        {           
            CourseInfo courseInfo = new ("ComputerScience", 2009);
            CourseInfo courseRecommendations = await context.CallActivityAsync<CourseInfo>(
                "CourseRecommendations", courseInfo);
            return courseRecommendations;
        }

        [Function("CourseRecommendations")]
        public static async Task<CourseInfo> Mapper(
            [ActivityTrigger] CourseInfo studentInfo, FunctionContext executionContext)
        {
            CourseInfo courseInfo = new (studentInfo.Major, studentInfo.UniversityYear);
            return courseInfo;   
        }

We are working on updating the doc with these details and publish soon. Sorry for the inconvenience caused by this.

I hope this helps and let us know if any questions.

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