Gateway
The gateway contract is the “glue”, that brings all the library concepts together. It is responsible for sending the request, handling the communication (by delegation to the other components) logging communication and returning the domain response by using mapper. It is represented by interface GatewayInterface and the implementation Gateway. The contract also offers a way of changing the individual components of a remote communication - adapter and logger.
Additional Functionality
As with almost every component, the gateway needed a way of “extending” the base functionality. By offering base contract GatewayInterface it is possible to use multiple suitable structural design patterns. By using this approach, we have implemented the Proxy capable of caching of any successfully performed request and store its response into PSR cache.