POC-golang-postgres-docker/internal/app/db.go

package app

import (
	"database/sql"
	"fmt"
	"os"
)

const (
	dbhost = "dbhost"
	dbport = "dbport"
	dbuser = "dbuser"
	dbpass = "dbpass"
	dbname = "dbname"
)

const (
	SqlGetUser = `
		SELECT
     		user_id,
			title,
			created_on,
			uuid
			
		FROM users
		WHERE title=$1;
		`
	SqlPostUser = `
INSERT INTO users (title, created_on,uuid)
VALUES ($1, $2, $3)
RETURNING user_id`
)

var Db *sql.DB

func InitDb() {
	config := dbConfig()
	var err error
	psqlInfo := fmt.Sprintf("postgres://%v:%v@%v:%v/%v?sslmode=disable",
		config[dbuser], config[dbpass],
		config[dbhost], config[dbport], config[dbname])

	fmt.Println(psqlInfo)
	Db, err = sql.Open("postgres", psqlInfo)
	if err != nil {
		panic(err)
	}
	err = Db.Ping()
	if err != nil {
		panic(err)
	}
	fmt.Println("Successfully connected!")
}

func CloseDB() {
	Db.Close()
}

func dbConfig() map[string]string {

	conf := make(map[string]string)

	host, ok := os.LookupEnv(dbhost)
	if !ok {
		panic("DBHOST environment variable required but not set")
	}
	port, ok := os.LookupEnv(dbport)
	if !ok {
		panic("DBPORT environment variable required but not set")
	}
	user, ok := os.LookupEnv(dbuser)
	if !ok {
		panic("DBUSER environment variable required but not set")
	}
	password, ok := os.LookupEnv(dbpass)
	if !ok {
		panic("DBPASS environment variable required but not set")
	}
	name, ok := os.LookupEnv(dbname)
	if !ok {
		panic("DBNAME environment variable required but not set")
	}

	conf[dbhost] = host
	conf[dbport] = port
	conf[dbuser] = user
	conf[dbpass] = password
	conf[dbname] = name
	return conf
}