Chapter 8:
Challenge yourself

This part is optional! The best way to learn anything new is to challenge your understanding. In this chapter, you’ll test out what you’ve learnt and pick up some new skills.

Challenge: Make the app a multi-user application

Anvil provides a built-in user authentication service that takes care of sign-up, sign-in and user permissions for you. Right now, anyone who opens up our news aggregator app can add, edit and delete all articles.

In this challenge, we’ll turn our app into a multi-user application so that users have to sign-in before they can access the app.

Add the Users Service

In the Sidebar Menu, click the blue plus button Add Service Icon and add the Users Service. You’ll see a screen with different configuration options and an empty table of Users at the bottom.

Configure the login process to your preference. Should new users be able to use their accounts right away? Should users be able to login with Google?

Present a login form

Next, modify the __init__ of your Homepage code to present users with a login form:


For more information and help with login forms, see the documentation: Anvil Docs | Presenting a Login Form.

Now, add a column to your Articles table that links to a row of the Users table (if you’ve forgotton how to do this, revisit step 4 of this tutorial) and update your add_article server function to store the currently logged in user when adding a row in the Articles table.

(Hint: You can get the currently logged-in user with anvil.users.get_user(). Read more in the documentation: Anvil Docs | User Permissions)

Display the user’s articles

Next, modify the get_articles() server function to only return rows from the Article Data Table where the currently logged-in user matches the user in the Users column.

Allow users to log out

Finally, add a Link or a Button to the app bar in your app and create a click event on it that logs out the current user with anvil.users.logout(). Also in that click event function, reload the app so that the login form is displayed.

(Hint: You can do this with open_form. Learn more about navigation in the documentation: Anvil Docs | Navigation)

Try it out

Test out your app by creating multiple accounts and adding news articles. Stuck? Why not ask a question on the Anvil Community Forum?

For a walkthrough of this challenge, check out the full tutorial on extending the news aggregator app to be a multi-user application:

Congratulations, you've completed this chapter!