HTTP 500 error from HTTP Triggered Azure Function even though Log Stream indicates successful completion of the function

Matthew Castrigno 5

I have a HTTP Triggered function that runs locally in Visual Studio fine. Monitoring in the Log Stream also show successful completion. However, the browser shows a 500 error even though there is nothing to return to the browser. How can I get rid of this error message?

    public static class ValidateFunction

    {

        [FunctionName("Validate")]

        public static async Task Run(

            [HttpTrigger(AuthorizationLevel.Anonymous, "get", "post", Route = null)] HttpRequest req,

            ILogger log)

        {

            log.LogInformation("Validate HTTP trigger function processed a request.");

            var responsebody = await HttpService.LeanIXAPI.Validate();

            var writeResponse = FtpService.WriteFTP.WriteToArcherFTP(responsebody, "test", "./ValidationResults.txt");

            log.LogInformation($"Validate response was: {writeResponse}");

            return;

        }

    }

Matthew Castrigno 5 Reputation points

2024-03-28T22:15:03.9466667+00:00
I also tried adding a timeout to host.json.

The error message comes after about 3 minutes.

{ "functionTimeout": "00:20:00" }

hossein jalilian 2,535

Thanks for posting your question in the Microsoft Q&A forum.

Could you please test this code and verify whether it successfully captures your errors?

public static class ValidateFunction
{
    [FunctionName("Validate")]
    public static async Task<IActionResult> Run(
        [HttpTrigger(AuthorizationLevel.Anonymous, "get", "post", Route = null)] HttpRequest req,
        ILogger log)
    {
        try
        {
            log.LogInformation("Validate HTTP trigger function processed a request.");    
             var responsebody = await HttpService.LeanIXAPI.Validate();
             var writeResponse = FtpService.WriteFTP.WriteToArcherFTP(responsebody, "test", "./ValidationResults.txt");            
            log.LogInformation($"Validate response was: {writeResponse}");

            return new OkResult(); 
         }   
      catch (Exception ex)     
        {           
           log.LogError(ex, "Error occurred in Validate function");     
            return new StatusCodeResult(StatusCodes.Status500InternalServerError);
         }
     }
 }

Please don't forget to close up the thread here by upvoting and accept it as an answer if it is helpful

MayankBargali-MSFT 68,476 Reputation points

2024-04-02T05:55:49.9966667+00:00

@Matthew Castrigno Thanks for reaching out and apology for the inconvenience due to this issue. For 500 errors it looks like there is a runtime exception in your function app and strange as it should not show you the successful execution. Can you review your application insights logs or Diagnose and solve problems blade on your function app to get more insights on 500 error. As per your code the 500 error could have occurred as your function app couldn't write the file to your FTP service. Can you also validate if your ValidationResults.txt file exists on your function app. The application insights log or diagnose and solve problem can give more insights on the actual issue.

In case if you couldn't figure it out then please let me know so I can connect offline to review it.
Matthew Castrigno 5 Reputation points

2024-04-02T14:56:00.19+00:00

Nothing in application insights provides any details of any error. The error simply shows in the browser. The end product of the function the ValidationResults.txt file is successfully created and written to it's intended destination.
MayankBargali-MSFT 68,476 Reputation points

2024-04-03T05:43:41.5233333+00:00

@Matthew Castrigno Please refer to my private comment to share more details.
Tim Walter 1 Reputation point

2024-04-04T21:35:28.0533333+00:00
Found my issues, deleted this.