run-grpc

study grpc

protobuf install

$ brew install protobuf
$ go get google.golang.org/grpc/cmd/protoc-gen-go-grpc
$ go install google.golang.org/grpc/cmd/protoc-gen-go-grpc
$ which protoc-gen-go-grpc

proto buf pb

$ protoc --go_out=. --go-grpc_out=. proto/greet.proto
$ go mod tidy

$ protoc --proto_path=proto proto/*.proto --go_out=gen/
$ protoc --proto_path=proto proto/*.proto --go-grpc_out=gen/

go work

$ go work init
$ go work use ./tools/ ./tools/gopls/

google api

$ mkdir -p google/api
$ curl https://raw.githubusercontent.com/googleapis/googleapis/master/google/api/annotations.proto > google/api/annotations.proto
$ curl https://raw.githubusercontent.com/googleapis/googleapis/master/google/api/http.proto > google/api/http.proto

$ protoc -I . --grpc-gateway_out ./gen/ \
    --grpc-gateway_opt logtostderr=true \
    --grpc-gateway_opt paths=source_relative \
    --grpc-gateway_opt generate_unbound_methods=true \
    proto/greet.proto

mux

https://pkg.go.dev/github.com/gorilla/mux#section-readme
mux for gateway server
mux port != grpc port

buf cli

$ brew install bufbuild/buf/buf
$ buf --help

grpc-gateway

Proxy tool that converts Protocol Buffers and gRPC services into HTTP JSON endpoints.

$ go install \
    github.com/grpc-ecosystem/grpc-gateway/v2/protoc-gen-grpc-gateway \
    github.com/grpc-ecosystem/grpc-gateway/v2/protoc-gen-openapiv2 \
    google.golang.org/protobuf/cmd/protoc-gen-go \
    google.golang.org/grpc/cmd/protoc-gen-go-grpc

buf gen

version: v1
plugins:
  - name: go
    out: ../pkg
    opt:
      - paths=source_relative
  - name: go-grpc
    out: ../pkg
    opt:
      - paths=source_relative
  - name: grpc-gateway
    out: ../pkg
    opt:
      - paths=source_relative
      - generate_unbound_methods=true
  - name: openapiv2
    out: ../pkg

proto gen validate

$ go get github.com/envoyproxy/protoc-gen-validate

if vscode ext error

"protoc": {
    "path": "/usr/local/bin/protoc",
    "options": [
        "--proto_path=${workspaceRoot}/common/proto", # -> check
    ]
}

rpc type

Unary RPC (단일 RPC)

• simplest type of RPC
• a single request & a single response
  client -request-> server
  client <-response- server
• ex) authentication or data retrieval

Server Streaming RPC (서버 스트리밍 RPC)

• a single request & multiple messages in response
  client -request-> server
  client <-response(messages)- server
• client must wait for the server to send all of the messages before it can continue
• ex) downloading files || returning the results of a database query

Client Streaming RPC (클라이언트 스트리밍 RPC)

• multiple messages in request & a single response
  client -request(messages)-> server
  client <-response- server
• server must wait for the client to send all of the messages before it can send a response
• ex) uploading files || inserting multiple records into a database

Bidirectional Streaming RPC (양방향 스트리밍 RPC)

• client and server can send multiple messages to each other in either direction
  client <-multiple messages-> server
• client and server can continue sending messages until one of them closes the connection
• ex) real-time data exchange (chat applications or streaming media)

docs

https://grpc.io/docs https://grpc-ecosystem.github.io/grpc-gateway https://buf.build/docs