Azure Functions vs WebJobs – Which to choose

Both are code-first technologies targeting developers (as opposed to design-first workflow services). They enable the orchestration and integration of different business applications into a single workflow and provide more control over the performance of your workflow plus the ability to write custom code as part of the business process.

Azure WebJobs

WebJobs are a part of the Azure App Service that you can use to run a program or script automatically. There are two kinds of WebJob:

• Continuous. They execute in a continuous loop. For example, you could use a continuous WebJob to check a shared folder for a new photo.
• Triggered. Can be executed manually or on a schedule.

For determining the actions of your WebJob, you can write code in several different languages. For example, you can script the WebJob by writing code in a Shell Script (Windows, PowerShell, Bash). Alternatively, you can write a program in PHP, Python, Node.js, JavaScript or .NET and any of the languages supported by the framework.

Azure Functions

An Azure Functions is in many ways similar to a WebJob, the main difference between them being that you don’t need to worry about the infrastructure at all.

It is ideal for running small pieces of code in the cloud. Azure will automatically scale your function in response to demand demand, and with the consumption plan , you only pay for the time your code takes to run.

They can run on a series of different triggers like for example:

• HTTPTrigger. Executes in response to a request sent through the HTTP protocol.
• TimerTrigger. Enables execution according to a schedule.
• BlobTrigger. When a new blob is added to an Azure Storage account.
• CosmosDBTrigger. In response to new or updated documents in a NoSQL database.

Differences

	Azure WebJobs	Azure Functions
Automatic scaling	No	Yes
Development and testing in a browser	No	Yes
Pay-per-use pricing	No	Yes
Integration with Logic Apps	No	Yes
Package managers	NuGet if you are using the WebJobs SDK	Nuget and NPM
Can be part of an App Service application	Yes	No
Provides close control of JobHost	Yes	No

Conclusions

Azure Functions are in general more flexible and easier to administrate. However, WebJobs are a better solution when:

• You want the code to be a part of an existing App Service application and to be managed as part of that application, for example in the same Azure DevOps environment.
• You need close control over the object that listens for events that trigger the code.