How To Develop And Deploy Azure WebJobs In Azure App Service

What is Azure WebJobs?

Azure WebJob is a feature of Azure App Service that runs a program or script in the background using a WebApp or WebAPI context. There is no additional cost to use WebJob. There are two types of web jobs.

1. Continuous WebJob.
2. Triggered WebJob.

Continuous WebJob

• It starts immediately when Web Jobs is created.
• It runs in all instances of the Web App. You can optionally restrict the Web Jobs to a single instance.
• It supports remote debugging.

Triggered WebJob

• It starts manually or is triggered.
• It runs on a single instance for load balancing.
• It does not support remote debugging.

Developing Azure WebJob using Visual Studio

Here we will see how to develop Azure WebJobs using Visual Studio.

• Open Visual Studio 2019 and click Create a new project.
• Type Azure WebJob in the search box, choose Azure WebJob (.NET Framework) template, and click Next.
  
• Give the appropriate Project name and Solution name, choose the location, and select the Framework. Then click Create.
  
• This template creates a simple console application containing a program. cs with Main Method and Function. cs file.
  
• The WebJobs SDK looks for the Azure Storage connection string in the app. config file. So give the Azure Storage connection string like below.
  

Let’s create a manual trigger using the NoAutomaticTrigger attribute in the Function.cs file.

[NoAutomaticTrigger]
public void TriggerHandler(TextWriter log)
{
    try
    {
        log.WriteLine("Trigger is Fired");
    }
    catch (Exception ex)
    {
        log.WriteLine("Exception in Trigger Handler", ex);
        throw ex;
    }
}

In Program.cs file contains the main method, call the manual trigger using the JobHost function like below.

class Program
{
    // Please set the following connection strings in app.config for this WebJob to run:
    // AzureWebJobsDashboard and AzureWebJobsStorage
    static void Main()
    {
        var config = new JobHostConfiguration();
        
        if (config.IsDevelopment)
        {
            config.UseDevelopmentSettings();
        }
        
        var host = new JobHost(config);
        host.Call(typeof(Functions).GetMethod("TriggerHandler"));
    }
}

Deploy Azure WebJob In Azure App Service

• Build the solution in Release mode.
• Go to the bin/Release/net45 path of the application and add all the contents in a .zip file.
  
• Go to the Azure portal, select your App service then go to WebJobs and ADD a Job.
  
• Enter the Job name, and select the .zip file. Choose the type triggered. We can choose the Triggers by schedule or manually.
• The scheduled WebJob will be executed based on the provided CRON expression.
• Enter the CRON Expression and click OK.
  
• It will take a few minutes to add the Web Job.
• Then select the WebJob you uploaded and click the Run button.
  
• You can see the status changed to Running, click Logs to see the WebJobs details like below.
  
  

That’s it, I hope you have learned how to develop and deploy an Azure WebJobs in Azure App service. Feel free to fill up the comment box below if you need any assistance.