ExecutionContext is null to non-function methods via IoC, alternative to ExecutionContext.FunctionAppDirectory

Question

ExecutionContext is available to functon parameters.

However, it is not available to other methods via dependency inject, including Functions' constructor, like below:

    public class FunctionClass
    {   

        IOtherClass _otherclass;
       public FunctionClass(ExecutionContext  context,  //excetpion
                          IOtherClass otherclass)  //excetpion
       {
                 _otherclass = IOtherClass otherclass
       }

     [FunctionName("Car")]
        public async Task<IActionResult> Run(
        [HttpTrigger(AuthorizationLevel.Anonymous, "get", "post", Route = null)]
        HttpRequest req, ExecutionContext  context)
        {     
          }
    }

     public class OtherClass:IOtherClass
    {   
       public OtherClass(ExecutionContext  context)  //excetpion
       {}
    }

I need access to ExecutionContext.FunctionAppDirectory, but don't want to pass ExecutionContext around, because want to use IoC instead.

Is there an alternative way to get the value of ExecutionContext.FunctionAppDirectory?

VS 2017

Azure Functons 2.x

Answer 1

Based on current documentation, ExecutionContext is only available in the scope of a request when the function method is being invoked.

[FunctionName("Car")]
public async Task<IActionResult> Run(
    [HttpTrigger(AuthorizationLevel.Anonymous, "get", "post", Route = null)]
    HttpRequest req, 
    ExecutionContext context //<--
) {

    var path = context.FunctionAppDirectory;

    //...
}

It wont be available as yet in the constructor for injection when the function class is initialized.

Answer 2

We can use ExecutionContextOptions to get application folder:

public class FunctionClass
  private ExecutionContextOptions context;

  public FunctionClass(IOptions<ExecutionContextOptions> executionContext) {
    this.context = executionContext.Value;

    var path = Path.GetFullPath(Path.Combine(context.AppDirectory, "extra.json"));

  }
}

Note: The above works using VS 2019 and Azure Functions 3.x

See:

• Github issue
• Related post