crud.go

package main

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

	"github.com/gorilla/mux"
)

// Item represents a simple item with ID and Name
type Item struct {
	ID   string `json:"id"`
	Name string `json:"name"`
}

var items []Item

// CORS middleware
func enableCORS(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		// Add CORS headers
		w.Header().Set("Access-Control-Allow-Origin", "*") // Allow all origins
		w.Header().Set("Access-Control-Allow-Methods", "POST, GET, OPTIONS, PUT, DELETE")
		w.Header().Set("Access-Control-Allow-Headers", "Content-Type, Authorization")
		if r.Method == "OPTIONS" {
			w.WriteHeader(http.StatusOK)
			return
		}
		next.ServeHTTP(w, r)
	})
}

func createItem(w http.ResponseWriter, r *http.Request) {
	var item Item
	_ = json.NewDecoder(r.Body).Decode(&item)
	items = append(items, item)
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(item)
}

func getItems(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(items)
}

func updateItem(w http.ResponseWriter, r *http.Request) {
	params := mux.Vars(r)
	for index, item := range items {
		if item.ID == params["id"] {
			items = append(items[:index], items[index+1:]...)
			var updatedItem Item
			_ = json.NewDecoder(r.Body).Decode(&updatedItem)
			updatedItem.ID = params["id"]
			items = append(items, updatedItem)
			w.Header().Set("Content-Type", "application/json")
			json.NewEncoder(w).Encode(updatedItem)
			return
		}
	}
}

func deleteItem(w http.ResponseWriter, r *http.Request) {
	params := mux.Vars(r)
	for index, item := range items {
		if item.ID == params["id"] {
			items = append(items[:index], items[index+1:]...)
			break
		}
	}
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(items)
}

func main() {
	router := mux.NewRouter()

	// CRUD routes
	router.HandleFunc("/items", createItem).Methods("POST")
	router.HandleFunc("/items", getItems).Methods("GET")
	router.HandleFunc("/items/{id}", updateItem).Methods("PUT")
	router.HandleFunc("/items/{id}", deleteItem).Methods("DELETE")

	// Root route
	router.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
		w.Write([]byte("Welcome to the Go CRUD API"))
	}).Methods("GET")

	// Apply CORS middleware
	log.Fatal(http.ListenAndServe(":8000", enableCORS(router)))
}