implement atlas for db migration

atlas.hcl

@@ -0,0 +1,11 @@
+env "local" {
+  src = "file://migrations/schema.sql"
+  url = "postgres://postgres:postgres@localhost:5433/go_weather?sslmode=disable"
+  dev = "docker://postgres/16/alpine/dev"  # for schema validation
+}
+
+env "production" {
+  src = "file://migrations/schema.sql"
+  url = "postgres://${env("DB_USER")}:${env("DB_PASSWORD")}@${env("DB_HOST")}:${env("DB_PORT")}/${env("DB_NAME")}?sslmode=require"
+  dev = "docker://postgres/16/alpine/dev"
+}

main.go

@@ -60,11 +60,6 @@ func main() {
 	defer database.Close()
 	databaseService := services.NewDatabaseService(database)
 
-	// Setup weather_readings table
-	if err := databaseService.CreateTable(); err != nil {
-		log.Fatalf("failed to create table: %v", err)
-	}
-
 	// Create services
 	weatherService := services.NewWeatherService(config.APIKey)
 

migrations/schema.sql

@@ -0,0 +1,9 @@
+CREATE TABLE IF NOT EXISTS weather_readings (
+    id SERIAL PRIMARY KEY,
+    city TEXT NOT NULL,
+    temp DOUBLE PRECISION NOT NULL,
+    feels_like DOUBLE PRECISION NOT NULL,
+    humidity INTEGER NOT NULL,
+    conditions TEXT NOT NULL,
+    fetched_at TIMESTAMP WITH TIME ZONE NOT NULL
+)

services/database.go

@@ -32,26 +32,6 @@ func NewDatabaseService(db *sql.DB) *DatabaseService {
 	return &DatabaseService{db: db}
 }
 
-func (s *DatabaseService) CreateTable() error {
-	_, err := s.db.Exec(`
-		CREATE TABLE IF NOT EXISTS weather_readings (
-			id SERIAL PRIMARY KEY,
-			city TEXT NOT NULL,
-			temp DOUBLE PRECISION NOT NULL,
-			feels_like DOUBLE PRECISION NOT NULL,
-			humidity INTEGER NOT NULL,
-			conditions TEXT NOT NULL,
-			fetched_at TIMESTAMP WITH TIME ZONE NOT NULL
-		)
-	`)
-
-	if err != nil {
-		log.Printf("failed to create table: %v", err)
-	}
-	fmt.Println("weather_readings table ready")
-	return nil
-}
-
 func (s *DatabaseService) SaveReading(weather models.WeatherResponse) (int, error) {
 	conditions := ""
 	if len(weather.Weather) > 0 {