Protocol Buffer HTTP Example

This project demonstrates a simple HTTP server that accepts JSON requests and returns Protocol Buffer responses.

Prerequisites

1. Go 1.21 or later
2. Protocol Buffer Compiler (protoc)

Installing Prerequisites

macOS

# Install Go
brew install go

# Install Protocol Buffer Compiler
brew install protobuf

Setup

1. Clone the repository:

git clone https://github.com/your-username/proto-http.git
cd proto-http

2. Install the Protocol Buffer compiler plugin for Go:

export PATH=$PATH:$(go env GOPATH)/bin && go install google.golang.org/protobuf/cmd/protoc-gen-go@latest

3. Generate Protocol Buffer code:

chmod +x generate.sh
./generate.sh

4. Install dependencies:

go mod tidy

Running the Server

Start the server:

go run main.go

The server will start on port 8080.

Testing the API

Using curl

1. Get a user (returns protobuf):

curl http://localhost:8080/user?id=1

2. Create a user (JSON input, protobuf output):

curl -X POST \
  http://localhost:8080/user \
  -H 'Content-Type: application/json' \
  -d '{
    "id": "2",
    "name": "Jane Doe",
    "email": "jane@example.com"
}'

Using Postman

1. GET Request:

   • URL: http://localhost:8080/user?id=1
   • Method: GET
   • Response will be in protobuf format

2. POST Request:

   • URL: http://localhost:8080/user
   • Method: POST
   • Headers: Content-Type: application/json
   • Body (raw JSON):

     {
       "id": "2",
       "name": "Jane Doe",
       "email": "jane@example.com"
     }

   • Response will be in protobuf format

Project Structure

• api/user.proto: Protocol Buffer definition
• server/server.go: HTTP server implementation
• main.go: Server startup code
• generate.sh: Script to generate Go code from proto files