Put project modules under pkg directory

pkg/cgnolink/database/database.go

@@ -0,0 +1,65 @@
+package database
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"github.com/jackc/pgx/v4/pgxpool"
+	"github.com/knadh/koanf"
+	"github.com/rs/zerolog/log"
+	"time"
+)
+
+func InitPool(config *koanf.Koanf) *pgxpool.Pool {
+	pool := NewPool(config)
+
+	if err := runMigrations(pool); err != nil {
+		log.Fatal().Err(err).Msg("Couldn't apply migrations")
+		panic(err)
+	}
+
+	return pool
+}
+
+func NewPool(config *koanf.Koanf) *pgxpool.Pool {
+	connStr, err := getConnectionString(config)
+	if err != nil {
+		log.Fatal().Err(err).Msg("Couldn't construct DB connection string")
+		panic(err)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+
+	pool, err := pgxpool.Connect(ctx, connStr)
+	if err != nil {
+		log.Fatal().Err(err).Msg("Couldn't connect to DB")
+		panic(err)
+	}
+
+	return pool
+}
+
+func getConnectionString(config *koanf.Koanf) (string, error) {
+	username := config.String("db.username")
+	if username == "" {
+		return "", errors.New("database username is missing")
+	}
+
+	password := config.String("db.password")
+	if password == "" {
+		return "", errors.New("database password is missing")
+	}
+
+	name := config.String("db.name")
+	if name == "" {
+		return "", errors.New("database name is missing")
+	}
+
+	host := config.String("db.host")
+	if name == "" {
+		return "", errors.New("database host is missing")
+	}
+
+	return fmt.Sprintf("postgresql://%s:%s@%s/%s", username, password, host, name), nil
+}