Building REST APIs with Go

Why Go for APIs?

Go compiles to a single binary with no runtime dependencies, handles concurrency natively with goroutines, and provides excellent performance. It's ideal for building fast, reliable API services.

Project Setup

mkdir myapi && cd myapi
go mod init myapi

Basic HTTP Server

package main

import (
    "encoding/json"
    "log"
    "net/http"
)

type Response struct {
    Message string `json:"message"`
    Status  int    `json:"status"`
}

func healthHandler(w http.ResponseWriter, r *http.Request) {
    w.Header().Set("Content-Type", "application/json")
    json.NewEncoder(w).Encode(Response{
        Message: "OK",
        Status:  200,
    })
}

func main() {
    http.HandleFunc("/health", healthHandler)
    log.Println("Server starting on :8080")
    log.Fatal(http.ListenAndServe(":8080", nil))
}

Build and Deploy

# Build for Linux
GOOS=linux GOARCH=amd64 go build -o myapi

# Run on server
./myapi

Systemd Service

[Unit]
Description=My Go API
After=network.target

[Service]
Type=simple
User=www-data
ExecStart=/opt/myapi/myapi
Restart=always
RestartSec=5
Environment="PORT=8080"

[Install]
WantedBy=multi-user.target

Performance Tips

• Go's net/http handles thousands of concurrent connections out of the box
• Use connection pooling for database access (sql.DB does this automatically)
• Profile with go tool pprof to find bottlenecks
• Use sync.Pool for frequently allocated objects