In this tutorial, we'll explore how to create a RESTful API using Go, a powerful programming language known for its performance and simplicity. We'll use the standard library along with the popular Gorilla Mux router to handle HTTP requests and responses.

 

 

package main

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

    "github.com/gorilla/mux"
)

type Book struct {
    ID     string  `json:"id"`
    Title  string  `json:"title"`
    Author string  `json:"author"`
    Price  float64 `json:"price"`
}

var books []Book

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

    router.HandleFunc("/books", getBooks).Methods("GET")
    router.HandleFunc("/books/{id}", getBook).Methods("GET")
    router.HandleFunc("/books", createBook).Methods("POST")
    router.HandleFunc("/books/{id}", updateBook).Methods("PUT")
    router.HandleFunc("/books/{id}", deleteBook).Methods("DELETE")

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

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

func getBook(w http.ResponseWriter, r *http.Request) {
    w.Header().Set("Content-Type", "application/json")
    params := mux.Vars(r)
    for _, item := range books {
        if item.ID == params["id"] {
            json.NewEncoder(w).Encode(item)
            return
        }
    }
    json.NewEncoder(w).Encode(&Book{})
}

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

func updateBook(w http.ResponseWriter, r *http.Request) {
    w.Header().Set("Content-Type", "application/json")
    params := mux.Vars(r)
    for index, item := range books {
        if item.ID == params["id"] {
            books[index] = Book{
                ID:     params["id"],
                Title:  item.Title,
                Author: item.Author,
                Price:  item.Price,
            }
            json.NewEncoder(w).Encode(books[index])
            return
        }
    }
    json.NewEncoder(w).Encode(&Book{})
}

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

 

This is a basic example of how to build a RESTful API with Go. We define routes for CRUD operations on a collection of books. The Gorilla Mux router helps us handle different HTTP methods and route parameters easily.