gRPC + Google Cloud ESP codebase containing real world examples (CRUD, auth, advanced patterns, etc) that adheres to the RealWorld spec and API.

Demo    RealWorld

This codebase was created to demonstrate a fully fledged fullstack application built with gRPC + Google Cloud ESP including CRUD operations, authentication, routing, pagination, and more.

We've gone to great lengths to adhere to the gRPC community styleguides & best practices.

For more information on how to this works with other frontends/backends, head over to the RealWorld repo.

How it works

The application uses gRPC + Google Cloud ESP.

gRPC is an open source high performance RPC framework released by Google. It supports multiple language and the RPC uses Google's Protocol Buffer as IDL.

Cloud Endpoints is an API Management framework to develop, deploy and manage APIs on Google Cloud Platform. Extensible Service Proxy (ESP) is an API relay/control plane offered by Cloud Endpoints for OpenAPI and gRPC. For gRPC, ESP provides JSON/REST to gRPC/Protobuf transcoding which means one can build a pure gRPC API and have ESP translate it into REST API with minimum configurations.

This repo uses bazel to build, latest working version is 5.3.2.

Getting started

Start the gRPC server to listen at port 8080

bazel run src/main/java/realworld:realworldserver

Re-generate the API descriptor set (optional)

bazel run "@com_google_protobuf//:protoc"
bazel-bin/external/com_google_protobuf/protoc --proto_path=. --proto_path=bazel-genfiles/external/com_google_protobuf/ --include_imports --include_source_info --descriptor_set_out=api_descriptor.pb src/main/realworld/proto/realworld.proto

Deploy ESP configurations to GCP

gcloud endpoints services deploy src/main/realworld/proto/api_descriptor.pb src/main/realworld/proto/api_config.yaml

Start a local ESP to transcode REST to gRPC

sudo docker run --detach --name="esp" --publish=8082:8082 --volume=$HOME/Downloads:/esp gcr.io/endpoints-release/endpoints-runtime:1.13.0 --service=realworld.endpoints.[YOUR PROJECT ID].cloud.goog --rollout_strategy=managed --http_port=8082 --backend=grpc://docker.for.mac.localhost:8080 --service_account_key=/esp/service-account-creds.json --transcoding_always_print_primitive_fields

Not that "transcoding_always_print_primitive_fields" option is required in order to make ESP transcoding to populate fields with default value, such as empty list, boolean field in false, integer at 0, etc.

To run unit tests

One unit test implemented under src/test/realworld/processors

bazel test src/test/java/realworld/processors:LoginUserRequestValidatorTest
bazel test src/test/java/realworld/processors:LoginUserRequestProcessorTest