ozon-task/internal/storage/db/postgres.go

package db

import (
	"fmt"
	"log"
	"os"

	"git.obamna.ru/erius/ozon-task/graph/model"
	"gorm.io/driver/postgres"
	"gorm.io/gorm"
	"gorm.io/gorm/logger"
)

var (
	host   = os.Getenv("APP_POSTGRES_HOST")
	port   = os.Getenv("APP_POSTGRES_PORT")
	user   = os.Getenv("APP_POSTGRES_USER")
	passwd = os.Getenv("APP_POSTGRES_PASSWORD")
	db     = os.Getenv("APP_POSTGRES_DB")
	con    = fmt.Sprintf("postgres://%s:%s@%s:%s/%s", user, passwd, host, port, db)
)

func InitPostgres() (*Database, error) {
	log.Printf("connecting to PostgreSQL database at %s...", con)
	// PrepareStmt is true for caching complex sql statements when adding comments or replies
	db, err := gorm.Open(postgres.Open(con), &gorm.Config{
		PrepareStmt: true,
		Logger:      logger.Default.LogMode(logger.Info),
	})
	if err != nil {
		log.Printf("failed to connect to database: %s", err)
		return nil, err
	}
	log.Println("opened connection to PostgreSQL database")
	log.Println("migrating model schema to database...")
	err = db.AutoMigrate(&model.Post{}, &model.Comment{})
	if err != nil {
		log.Printf("failed to automatically migrate model schema: %s", err)
		return nil, err
	}
	log.Println("finished migrating model schema")
	return InitDatabase(db), nil
}