F# class in Azure isolated process function. No job functions found

Question

I could not create an Azure isolated process function if I use F# class semantics, it works with the native F# function semantic. Could someone please take a look? Thank you!

The error is: No job functions found. Try making your job classes and methods public. If you're using binding extensions [...more...]

module Functions

open Microsoft.Azure.Functions.Worker
open Microsoft.Extensions.Logging

// this works, but could not use dependency registered in Host
[<Function("TimerTriggerFunction")>]
let TimeIntervalFunction ([<TimerTrigger("*/10 * * * * *")>] myTimer: TimerInfo) (context: FunctionContext) =
    let logger = context.GetLogger("")
    logger.LogInformation("function is triggered!")


// I need dependency injection but this doesn't work
type TimeIntervalFunctionClass() =
        
    [<Function("TimerTriggerFunction")>] 
    member this.Run ([<TimerTrigger("*/3 * * * * *")>] myTimer: TimerInfo) (context: FunctionContext) =
        context.GetLogger("test").LogInformation("finally")

Answer 1

Hello @Tri Nguyen

One thing to note is that the Function attribute should be applied to a method, not a class. In your example, you have applied the attribute to the TimeIntervalFunctionClass class, which might be causing the issue. Instead, you should define a public method inside the class and apply the Function attribute to that method. Here's an example of how you can define a public method inside the TimeIntervalFunctionClass class and apply the Function attribute to that method:

open Microsoft.Azure.Functions.Worker
open Microsoft.Extensions.Logging
type TimeIntervalFunctionClass() = [] 
	member this.Run ([] myTimer: TimerInfo) (context: FunctionContext) = 
	let logger = context.GetLogger() logger.LogInformation("finally")

In this example, the Run method is marked with the Function attribute and takes a TimerInfo parameter and a FunctionContext parameter. The TimerTrigger attribute is applied to the myTimer parameter to specify the timer trigger schedule. The FunctionContext parameter is used to get a logger instance, which can be used to log information.

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