You can integrate the SDK with your own authorization system. To do this, implement user identification by custom ID (user ID generated on your server) to open an in-game store, make a payment, and manage inventory.

The flow of interaction with Xsolla servers when using your own authorization system:

1. Your client sends an authentication request to your server.
2. Your server authorizes the user and sends a request to the Xsolla server to receive the user JSON Web Token (JWT), passing in the custom ID.
3. Xsolla server returns the user JWT.
4. Your server passes the user JWT to the client.
5. SDK methods use the received user JWT instead of authorization token to open an in-game store, make a payment, and manage inventory.

To use your own authorization system with Xsolla products:

1. Set up server OAuth 2.0 client in your Publisher Account.
2. Implement getting the server JWT.
3. Implement getting the user JWT.
4. Implement the logic of working with the in-game store, purchases, and inventory using the user JWT.

Set up server OAuth 2.0 client

1. Open your project in Publisher Account and go to the Login section.
2. Click Configure in the pane of a Login project.
3. Go to the Security block and select the OAuth 2.0 section.
4. Click Add OAuth 2.0.
5. Specify OAuth 2.0 redirect URIs.
6. Check the Server (server-to-server connection) box.
7. Click Connect.
8. Copy and save the client ID and secret key.

Get server JWT

On the back end of your application, implement a method to get the server JWT using the Generate JWT API call. The request must contain the following parameters:

• grant_type is the JWT type, pass the client_credentials value.
• client_secret is the secret key that is received when you set up the server OAuth 2.0 client.
• client_id is the client ID received when you set up the server OAuth 2.0 client.

Get user JWT

On the back end of your application, implement a method to get the user JWT using the Auth by custom ID API call. The request must contain the X-Server-Authorization: <server_JWT> header, where <server_JWT> is the server JWT obtained in the previous step.

Use user JWT

Use the SDK methods to open the in-game store, make a payment, and manage inventory. While using the SDK methods, pass the user JWT to the Token.Instance property.

The following tutorials contain examples of using the token:

• Sell virtual items for real currency
• Sell virtual items for virtual currency
• Display of virtual currency balance
• Display of items in inventory

Implement the logic of receiving a new user JWT after its expiration. It is recommended that you get a new token in background mode so the user doesn’t have to log in to the application again.