Azure Static Web App–Traffic splitting

As a follow-up on the presentation I did at CloudBrew about Azure Static Web Apps I want to write a series of blog posts.

Yesterday I talked about limiting access to your staging environment by password protecting it. This allows you to work with a limited set of test users who can access the staging environment(assuming they got the visitor password).

However sometimes you want to do something like a canary deployment where we redirect a small subset of your users in production to a new version of your application.

This is something that is also possible in Azure Static Web Apps through the concept of Traffic splitting. To activate this feature go to your Azure static web app resource in the Azure portal:

• Go to Environments.

• Choose Traffic splitting at the top. This will open the Traffic splitting pane.

  

• There we can add an extra environment by clicking Add. We need to select an environment and specify the amount of traffic that should be redirected to this environment.

Click Save to commit your changes.

Now a part of our users will go to the Production environment where some will end up on our PR environment.

Remark: To avoid strange behavior returning traffic will always go to the same environment.

If I now open 2 browser windows and browse to the production URL, we get two different pages(notice the difference in the title):

I wondered what would happen if I tried to combine this feature with the password protection I showed yesterday…

When I selected the Protect both staging and production environment option, I got the password request. When I  selected the Protect staging environments only option, I got to see the PR environment. This makes sense I think as a part of our production traffic is redirect behind the scenes.  I still cannot directly access the PR environment without providing the password.

More information

Traffic Splitting in Azure Static Web Apps (preview) | Microsoft Learn