Wiring gRPC service

Wiring an existing gRPC service to GJEX

This is done using Guice and extensions provided by GJEX as demonstrated in examples:

• Create a separate Gradle or Maven project for the new service.
• Generate the gRPC stubs using grpc-java
• Implement the concrete service, making use of GJEX extensions like - Configuration, Metrics etc. as seen in GreeterService
• Implement a Guice module to configure the gRPC service and its dependencies - such as a custom configuration. See HelloWorldModule and Service YAML file
• Implement a GJEX Application class that wires the gRPC service Module with the GJEX runtime. For e.g. HelloWorldApplication
• Build the project and run the GJEX Application, for e.g. HelloWorldApplication. With Gradle, this can be packaged as an executable. See examples build.gradle