grpc-demo

Introduction

• This is a demo app to demonstrate the basic communication using gRPC.
• There are two servers in this app: Python-FastAPI with a gRPC server and Java-SpringBoot with a gRPC server.

DDD Implementation

• I added a few DDD concepts to this app, but I only isolated layers where the functions are called from the inner layers.
  • The ports in Java are the interfaces that prevent my services from using infra code directly.
  • The adapters in Java are the implementation of the ports.
  • There are no ports in my Python code. I put my adapters in the services modules although this is not a standard architecture.

gRPC Communication

Clients (Blocking Stub)  -->  Java-SpringBoot --> Java-gRPC --> Python-gRPC

Clients (Ansync Stub) -->  Python-FastAPI --> Python-gRPC --> Java-gRPC

How to run the app

• Build the proto files.

# java
# Use Maven and IDEA to build the proto files.

# Python
python -m grpc_tools.protoc \
--proto_path=. \
--python_out=. \
--pyi_out=. \
--grpc_python_out=. \
./python_grpc_v2/infra/grpc/protos/greeting/greeting.proto

• Start the servers
  • Java: java-grpc-v2/infra/src/main/java/idv/sheng/java_grpc_v2/infra/JavaGrpcApplication.java
  • Python: python-grpc-v2/main.py
• Use Swagger to test the APIs
  • Java: http://127.0.0.1:8080/swagger-ui/index.html
  • Python: http://127.0.0.1:8000/docs