Azure WebJobs

Azure WebJobs are one of the underlying features of Azure App Service. They allow for the easy running of so-called "jobs" using different intervals, or even running them infinitely. They are very flexible and provide a special SDK, so users can work with them efficiently and quickly.

The following topics will be covered in this chapter:

• How to create Azure WebJobs
• Working with different trigger types (continuous and triggered)
• Using different file types for WebJobs

Technical requirements

To perform exercises from this chapter, you will need the following:

• Access to an Azure subscription
• Visual Studio 2017 with Azure development workload installed

Creating WebJobs

Working with WebJobs is much simpler than working with App Services, as this is a much easier service to configure and use. In fact, there are two ways of working with them:

• Using Azure Portal and deploying a job manually
• Using Visual Studio to develop and deploy it manually

What is more, you can leverage the WebJobs SDK to prepare an application triggered by an external service. This will be covered at the end of this chapter, and will be an excellent introduction to Azure Functions, described later in this book.

Creating and deploying WebJobs in Azure Portal

The easiest and quickest way to start working with WebJobs is to create a custom console application, perform an action, and then deploy it using...

Using different file types for WebJobs

When you are working with WebJobs, you are not limited to using EXE files. Currently, this service supports the following applications:

• Windows executables (.exe, .bat, and .cmd)
• Powershell (.ps1)
• Bash (.sh)
• Python (.py)
• PHP (.php)
• Node.js (.js)
• Java (.jar)

As you can see, the preceding list is quite similar to the supported languages in App Services. This should be understandable now, as you have learned that WebJobs are in fact an integral part of Web Apps in Azure. Let's try something practical—we will deploy a simple Node.js application, which will publish to Azure as a WebJob.

Creating and deploying a Node.js application as a WebJob

JavaScript is one of the most popular...

Summary

As you have seen, Azure WebJobs are a really helpful and useful feature of App Services that let you quickly develop jobs running either continuously or triggered on schedule. They start to shine when you have a working web app, which could be used to host them and execute many different actions asynchronously (such as generating a report or reading a queue, which will feed your application's database later). Thanks to the support of different programming languages, you do not have to limit yourself to only one particular platform. Last but not least, they are a great introduction to Azure Functions, which are one of the most popular services in Azure and extend the current possibilities of WebJobs even further. In Chapter 3, Deploying Web Applications as Containers, you will learn about deploying Web Apps as containers, what extends even more the capabilities of...

Questions

1. Can you run WebJobs using the Free or Shared tier?
2. What run modes does WebJobs currently supprt?
3. Can you run a Java application using WebJobs?
4. How can you ensure that runtime will find your job starting file?
5. Can you publish a WebJob containing more than only one file? If so, how can you do that?
6. How can you ensure that a WebJob will not be scaled out to multiple instances?
7. Can a WebJob access the application settings of the App Service that hosts it?

Further reading

• https://docs.microsoft.com/en-us/azure/app-service/webjobs-sdk-how-to