Documentation: Creating and communicating with microservices.

User Story

There are multiple ways to set up microservices:

• Have a public facing API Gateway responsible for authentication, that then acts as a proxy for internal microservices, or which can have orchestration logic on top of their responses.
• Have many public facing services- one responsible for the process of authentication and the frontends are responsible for knowing.

There are also multiple ways to perform communication:

• Loopback 4 supports creating an OpenAPI JSON based datasource when using lb4 service.
• HTTP REST
• rpc, gRPC, redis/socket notifications.

There are different ways to organize the source code:

• A monorepository, using something like lerna to manage versioning and publishing.
• Separate repositories managed by different teams.

It would be great to have documentation and examples that could cover these cases. Example:

• Creating a loopback4 microservice as a REST Server that can expose an openapi.json file, and a loopback4 api gateway responsible for authentication and consuming those microservices.
• Creating a loopback4 microservice as a gRPC server that can publish proto files (to a private repository, or just on github for consumption), and a loopback4 api gateway responsible for authenticating and consuming those microservices.
• Workflows for maintaining multiple services with minimal manual code intervention.

まず、lb4 service と OpenAPI JSON データソースに関する既存の LoopBack 4 ドキュメントを確認します。REST および gRPC マイクロサービス、API ゲートウェイ、認証、サービスの構成、複数サービスのワークフローを対象とする例の範囲を定義します。選択したケースについて完全なドキュメントと実行可能な例が揃っていれば完了としますが、この issue では更新対象のファイルやテストは特定していません。