Update storage tables when webjob is shutting down - azure

Question

My question is similar to the below one.
Notification of when continuous Azure WebJob is stopping for NoAutomaticTrigger type jobs
I have used the idea from Amit's Blog but then hit a little roadblock
I have a file watcher set in the webjob which gets triggered if the webjob is shutdown from the portal.
I need to update a few flags in my storage tables before the webjob is terminated.
The problem is that my code seems to stop at a point where I am trying to retrive a record from storage table. I have exception handler around the below code and no exception message is written on the console.
Below is my code
CloudStorageAccount storageAccount = CloudStorageAccount.Parse("my storage key");
var tableClient = storageAccount.CreateCloudTableClient();
var table = tableClient.GetTableReference("myTable");
TableOperation operation = TableOperation.Retrieve("partKey", "rowKey");
var result = table.Execute(operation); // stucks here
if (result.Result != null)
{
MyEntity entity = (MyEntity)result.Result;
if (entity != null)
{
entity.IsRunning = false; //reset the flag
TableOperation update = TableOperation.InsertOrReplace(entity);
table.Execute(update); //update the record
}
}
I have increased the stopping_wait_time in settings.job to 300 seconds but still no luck.

Answer 1

You could use Microsoft.Azure.WebJobs.WebJobsShutdownWatcher
This is an implementation of Amit solution : WebJobs Graceful Shutdown
So I've found a solution doing this :
No modification in the Program.cs
class Program
{
static void Main()
{
var host = new JobHost();
host.Call(typeof(Startup).GetMethod("Start"));
host.RunAndBlock();
}
}
the graceful shutdown goes in your function :
public class Startup
{
[NoAutomaticTrigger]
public static void Start(TextWriter log)
{
var token = new Microsoft.Azure.WebJobs.WebJobsShutdownWatcher().Token;
//Shut down gracefully
while (!token.IsCancellationRequested)
{
// Do somethings
}
// This code will be executed once the webjob is going to shutdown
Console.Out.WriteLine("Webjob is shuting down")
}
}
After the while loop, you could also stop started tasks.