POC-golang-postgres-docker/api.go

package main

import (
	"encoding/json"
	"fmt"
	"net/http"
	"time"
)

type User struct {
	UserID    int
	Title     string
	CreatedOn time.Time
}

type Users struct {
	users []User
}

func UserGetHandler(w http.ResponseWriter, req *http.Request) {
	if req.Method == "GET" {
		users := Users{}

		err := queryRepos(&users)
		if err != nil {
			http.Error(w, err.Error(), 500)
			return
		}

		out, err := json.Marshal(users.users)
		if err != nil {
			http.Error(w, err.Error(), 500)
			return
		}

		fmt.Fprintf(w, string(out))
	} else {
		fmt.Fprintf(w, "Sorry, only Get methods are supported for thus api.")
	}
}

func UserPostHandler(w http.ResponseWriter, req *http.Request) {
	if req.Method == "POST" {
		if err := req.ParseForm(); err != nil {
			fmt.Fprintf(w, "ParseForm() err: %v", err)
			return
		}
		title := req.FormValue("title")
		sqlInsert := `
INSERT INTO users (title, created_on)
VALUES ($1, $2)
RETURNING user_id`
		if len(title) > 0 {
			user_id := 0
			row := db.QueryRow(sqlInsert, title, time.Now())
			err := row.Scan(&user_id)
			if err != nil {
				panic(err)
			}
			fmt.Fprintf(w, "user creted")
		} else {
			fmt.Fprintf(w, "Invalid data")
		}
	} else {
		fmt.Fprintf(w, "Sorry, only POST methods are supported for thus api.")
	}
}

func queryRepos(users *Users) error {
	rows, err := db.Query(`
		SELECT
     		user_id,
			title,
			created_on
			
		FROM users;
		`)
	if err != nil {
		return err
	}
	defer rows.Close()
	for rows.Next() {
		user := User{}
		err = rows.Scan(
			&user.UserID,
			&user.Title,
			&user.CreatedOn,
		)
		if err != nil {
			return err
		}
		users.users = append(users.users, user)
	}

	err = rows.Err()
	if err != nil {
		return err
	}
	return nil
}