Azure function TimerTrigger only running once

Question

This is my Function.Json

{   "generatedBy": "Microsoft.NET.Sdk.Functions-1.0.28",   "configurationSource": "attributes",   "bindings": [
    {
      "type": "timerTrigger",
      "schedule": "*/5 * * * * *",
      "useMonitor": true,
      "runOnStartup": false,
      "name": "myTimer"
    }   ],   "disabled": false,   "scriptFile": "../bin/PullRequest.dll",   "entryPoint": "PullRequest.PullRequest.Run" }

This is my actual function:

[FunctionName("PullRequest")]
public static void Run([TimerTrigger("*/5 * * * * *")]TimerInfo myTimer, ILogger log)
{
     if (myTimer.IsPastDue)
     {
         log.LogInformation("Timer is running late!");
     }
     log.LogInformation($"C# Timer trigger function executed at: {DateTime.Now}");
}

When I tried to run this function on Azure portal then it only run once and stops.

this is the log of the Azure Funciton:

I rerun it and now it only running once.:

@Rafal Agree, but this cron expression is every 5 seconds I believe. — DavidG, Jul 02 '19 at 11:46
@DavidG /yes. I am not sure why it is not running. It only run once. — Ameya Deshpande, Jul 02 '19 at 12:08
The logs you have given us show it is running more than once though? — DavidG, Jul 02 '19 at 12:08
@DavidG I am re running the function. that is why it s showing multiple times — Ameya Deshpande, Jul 02 '19 at 12:09
@DavidG My bad David. The time given turns out to be 5 minutes not 5 seconds. — Ameya Deshpande, Jul 02 '19 at 12:21

score 1 · Answer 1 · edited Jun 20 '20 at 09:12

Like DavidG said: the Logs you're showing us, show that the function PullRequest ran at least 3 times.

Once where the executing log line isn't visible, so the reason is not clear
Once because the timer fired (@11:30:00)
Once because it was programmatically called via the host APIs (AKA manually)

Your CRON expression */5 * * * * * roughly translates into 'run this every time the number of seconds is divisible by 5'. That wouldn't match with the logs you're providing. Are you sure that's the CRON expression you're using?

Azure Functions uses the NCronTab library to interpret CRON expressions. A CRON expression includes six fields:

{second} {minute} {hour} {day} {month} {day-of-week}

Taken from Timer trigger for Azure Functions - CRON expressions.

EDIT:
Functions running on a Timer Trigger are automatically triggered on the specified timer intervals. To have the Functions actually run, you (of course) need to have something running that executes that trigger. Otherwise: how can they be triggered?

In Azure, the Functions Runtime is responsible for triggering the Function at the right time. Locally, the func.exe tool that starts automatically when you debug the application will do this for you. But if that doesn't run, nothing will happen.

Azure Functions Core Tools lets you develop and test your functions on your local computer from the command prompt or terminal. Your local functions can connect to live Azure services, and you can debug your functions on your local computer using the full Functions runtime.

and

To run a Functions project, run the Functions host. The host enables triggers for all functions in the project.

Taken from Work with Azure Functions Core Tools.

In short: "The host enables triggers. It needs to run to have something that triggers any Function".

Sure. Now When I have a window open then only it is running. I am not sure I am understanding it well though. could you redirect me to the right direction so that I can get more information. — Ameya Deshpande, Jul 02 '19 at 12:34

score 1 · Accepted Answer · answered Jul 02 '19 at 12:30

1

Time trigger will automatically execute as per CORN expression i.e. in your case this function will execute every five seconds and If you run it from azure portal it will run only once. If you want to check timings of last executions you can go to Monitor tab and check timings . I have executed this locally and its working as expected

answered Jul 02 '19 at 12:30

Agrawal Shraddha

734
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I do get a log that says running every 5 minutes from `monitor` tab. At least I am able to see that it is running. – Ameya Deshpande Jul 02 '19 at 12:33

Azure function TimerTrigger only running once

2 Answers2