How to create a simple RESTful API server with CRUD operations in Go?

To create a simple RESTful API server with CRUD operations in Go, you can follow these steps:

Create a new Go module for your project:

$ go mod init <module_name>

Import the required packages:

package main

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

	"github.com/gorilla/mux"
)

Define a struct for your data model:

type Todo struct {
	ID        string `json:"id,omitempty"`
	Title     string `json:"title,omitempty"`
	Completed bool   `json:"completed,omitempty"`
}

Implement the CRUD handlers:

var todos []Todo

func GetTodos(w http.ResponseWriter, r *http.Request) {
	json.NewEncoder(w).Encode(todos)
}

func CreateTodo(w http.ResponseWriter, r *http.Request) {
	var todo Todo
	json.NewDecoder(r.Body).Decode(&todo)
	todo.ID = uuid.New().String()
	todos = append(todos, todo)
	json.NewEncoder(w).Encode(todo)
}

func UpdateTodo(w http.ResponseWriter, r *http.Request) {
	params := mux.Vars(r)
	for index, item := range todos {
		if item.ID == params["id"] {
			todos = append(todos[:index], todos[index+1:]...)
			var todo Todo
			json.NewDecoder(r.Body).Decode(&todo)
			todo.ID = params["id"]
			todos = append(todos, todo)
			json.NewEncoder(w).Encode(todo)
			return
		}
	}
}

func DeleteTodo(w http.ResponseWriter, r *http.Request) {
	params := mux.Vars(r)
	for index, item := range todos {
		if item.ID == params["id"] {
			todos = append(todos[:index], todos[index+1:]...)
			break
		}
	}
	json.NewEncoder(w).Encode(todos)
}

Define and configure your routes:

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

	todos = append(todos, Todo{ID: "1", Title: "Task 1", Completed: false})
	todos = append(todos, Todo{ID: "2", Title: "Task 2", Completed: true})

	router.HandleFunc("/todos", GetTodos).Methods("GET")
	router.HandleFunc("/todos", CreateTodo).Methods("POST")
	router.HandleFunc("/todos/{id}", UpdateTodo).Methods("PUT")
	router.HandleFunc("/todos/{id}", DeleteTodo).Methods("DELETE")

	log.Fatal(http.ListenAndServe(":8000", router))
}

Build and run your application:

$ go build
$ ./<module_name>

Now you have a simple RESTful API server in Go with CRUD operations. You can use tools like curl or Postman to test the endpoints.