To implement the scenario you described, you can use Ory Hydra to become an OAuth 2.0 and OpenID Connect provider. This will allow you to manage user sessions across multiple websites (Website 1 and Website 2 in your case). Here's a step-by-step guide on how you can achieve this: 1. Set up Ory Hydra: Ory Hydra is not an identity management system, but it can connect to your existing identity management (for example, the one from Website 1). It is capable of issuing, in a secure and OpenID Certified manner, access, refresh, and ID tokens. You can run Hydra by adding its Docker image to your cluster. 2. Customize Ory OAuth2 and OpenID Connect: You need to customize Ory OAuth2 and OpenID Connect to work with your user database, login UI, and consent logic and UI. This involves redirecting users to your login endpoint, fetching and processing login and consent requests, and using the SDK to accept or reject these requests. You can find an example Node.js implementation of an app that implements custom login and consent on [Ory's GitHub](https://github.com/ory/hydra-login-consent-node). 3. Implement OAuth2 Flow: When a user logs into Website 1, the client initiates an OAuth2 request. This is where Hydra's user login & consent flow comes into play. Before Hydra can issue an access token, it needs to know which user is giving consent. To determine this, Hydra redirects the user to the login endpoint of Website 1. 4. Use Access Tokens: Once the user is authenticated and has given consent, Hydra will issue an access token. This token can be used to authenticate the user on Website 2. When the user is redirected to Website 2, the website can use the access token to verify the user's identity and log them in automatically. 5. Handle Cross-Origin Requests: If you have cross-origin requests, using OAuth2 can help you handle them securely. Making cookies work with cross-origin requests weakens or even disables important anti-CSRF measures. Please note that this is a high-level overview and the actual implementation can be complex. You might need to adjust these steps based on your specific requirements and infrastructure. For more detailed information, you can refer to the following documentation: - [Ory Hydra Documentation](https://www.ory.sh/docs/ecosystem/projects#ory-hydra) - [Customizing Ory OAuth2 and OpenID Connect](https://www.ory.sh/docs/oauth2-oidc/custom-login-consent/flow) - [Ory Hydra Case Study](https://www.ory.sh/docs/hydra/case-study) - [Performing OAuth 2.0 Flow](https://www.ory.sh/docs/hydra/self-hosted/configure-deploy#perform-oauth-20-flow)

Sure, here's a step-by-step guide on how to set up Ory Hydra in a non-Docker environment: 1. Install Ory Hydra: Ory Hydra is written in Go and you can install it directly from the source code. You can find the source code on [GitHub](https://github.com/ory/hydra). You'll need to have Go installed on your system to compile the code. 2. Configure Ory Hydra: After installing Ory Hydra, you'll need to configure it. The configuration can be done through a configuration file or environment variables. The configuration includes setting up the database connection, system secret, and other necessary parameters. You can find more details about the configuration in the [Ory Hydra documentation](https://www.ory.sh/docs/hydra/self-hosted/install). 3. Run Database Migrations: Ory Hydra uses a SQL database to store data. Before you can start Ory Hydra, you'll need to run database migrations. This can be done using the

hydra migrate sql

command. 4. Start Ory Hydra: After the database migrations are done, you can start Ory Hydra using the

hydra serve all

command. This will start all HTTP/2 APIs and connect to the database backend. 5. Secure the APIs: The APIs of Ory Hydra don't come with integrated access control. This means that all requests sent to their APIs are considered authenticated and authorized. You should protect access to their APIs using Ory Oathkeeper or a comparable API Gateway. Please note that this is a high-level guide and the actual steps might vary based on your specific requirements and infrastructure. For more detailed instructions, you can refer to the [Ory Hydra documentation](https://www.ory.sh/docs/hydra/self-hosted/install).