Using a reverse proxy
By running Keycloak in front of your application, you can use reverse proxies to add additional capabilities to your application. The most common proxies provide support for OpenID Connect where enabling authentication is a matter of changing the proxy configuration.
Whether using a proxy is better than having the integration code and configuration within your application really depends on the use case and, depending on the circumstances, it might be your only option or the option that will save you precious time from implementing your own integration code, even if you have a library available for the technology stack your application is using.
Nowadays, OpenID Connect and OAuth2 support is a mandatory capability for proxies, and you find support for these protocols in most of them, regardless of whether they’re open source or proprietary. As an example, two of the most popular proxies, Apache HTTP Server and Nginx, provide the necessary extensions...