Unlocking User Permissions in Xano

In the world of web and mobile applications, managing user permissions is crucial for ensuring data security and control over user actions. While assigning roles is a common approach, sometimes you need more granular control over user permissions. Xano's no-code platform provides a flexible solution for implementing granular user permissions, allowing you to define specific operations that individual users can or cannot perform.

In this guide, we'll walk you through the process of setting up granular user permissions in Xano, using a real-world example of parental controls. We'll cover the database structure, API functions, and demonstrate how it all works in action.

Prerequisites

Before we begin, make sure you have the following:

• A Xano workspace set up
• Basic understanding of Xano's data models and APIs

Step 1: Set up the Database Structure

In your Xano workspace, create the following tables:

1. Permissions Table: This table will store all the APIs in your application and the users who can access them.
2. Permission Requests Table: This table will keep track of user requests for specific permissions.
3. User Table: This is a standard user table with the following additional fields:

• `managed_users` (List Field): A list of table references to users that the current user can manage.
• `is_admin` (Boolean Field): Indicates whether the user is an administrator or not.

Step 2: Populate the Permissions Table

To populate the `Permissions` table with all the API endpoints in your workspace, you can use the prebuilt `populate_permissions` API available in the provided snippet.

This API leverages Xano's Metadata API to retrieve a list of all your API endpoints and populates them in the `Permissions` table.

1. Install the `populate_permissions` API from the snippet into your workspace.
2. Run the `populate_permissions` API.
3. Verify that the `Permissions` table is now populated with all your API endpoints, including their IDs and HTTP verbs.

Step 3: Check User Permissions

Now that the `Permissions` table is populated, you can start checking user permissions before allowing them to call specific APIs.

1. For each API endpoint that requires permission checking, enable authentication in the API settings.
2. In the function stack of the API, add the `check_permission` function as the first step.

• The `check_permission` function takes two parameters: the `api_id` and the `user_id` of the authenticated user.
• This function checks if the user has permission to call the API by querying the `Permissions` table and verifying if the user is explicitly allowed, if the API is accessible to all users, or if the user is an administrator (and the API is accessible to admins).

1. If the `check_permission` function returns data, it means the user has permission, and execution proceeds. If no data is returned, the API returns an "Unauthorized" error.

Step 4: Allow Users to Request Permissions

To enable users to request permissions for specific APIs, you can use the `permission_request` API from the provided snippet.

1. Install the `permission_request` API into your workspace.
2. Ensure that the user requesting permission has at least one manager assigned in the `managed_users` field of the `User` table.
3. Call the `permission_request` API with the `api_id` of the API for which the user wants to request permission.
4. The API checks if the user is allowed to request permissions and adds a record to the `Permission Requests` table.

Step 5: Manage Permission Requests

As an administrator or manager, you can manage permission requests using the `permission_requests_of_user` and `edit_permissions` APIs from the provided snippet.

1. Run the `permission_requests_of_user` API as an authenticated user (manager or admin).

• This API returns a list of users managed by the authenticated user and the APIs for which those users have requested permissions.

1. Review the permission requests and decide which users should be granted access to which APIs.
2. For each user and API combination you want to allow, call the `edit_permissions` API with the `api_id` and `user_id`.

• This API updates the `Permissions` table to grant the specified user access to the specified API.

Step 6: Test User Permissions

After setting up the permissions and granting access to users, you can test the user permissions by calling the APIs as different users.

1. Call an API endpoint as a user who has been granted permission.

• The API should execute successfully.

1. Call the same API endpoint as a user who has not been granted permission.

• The API should return an "Unauthorized" error.

1. Repeat the testing process for different user roles, such as regular users, managers, and administrators, to ensure the permissions are working as expected.

By following this guide, you can implement granular user permissions in your Xano application, giving you fine-grained control over user access and actions. This approach is particularly useful for scenarios like parental controls, where administrators (parents) need to manage permissions for individual users (children) on a per-operation basis.

Remember, the provided snippet includes all the necessary APIs and functions mentioned in this guide, making it easy for you to integrate granular user permissions into your Xano application.