feat: Remove godotenv. Replace it with our own function that reads .env on start

cmd/main.go

@@ -1,20 +1,48 @@
 package main
 
 import (
+	"bufio"
 	"log"
 	"net/http"
 	"os"
+	"strings"
 
 	"go-backend/internal/database"
 	"go-backend/internal/database/sqlc"
 	"go-backend/internal/handlers"
 	"go-backend/internal/services"
-
-	"github.com/joho/godotenv"
 )
 
+// loadEnvFile sets environment variables from a KEY=VALUE .env file,
+// without overriding vars already set in the environment.
+func loadEnvFile(path string) error {
+	f, err := os.Open(path)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	scanner := bufio.NewScanner(f)
+	for scanner.Scan() {
+		line := strings.TrimSpace(scanner.Text())
+		if line == "" || strings.HasPrefix(line, "#") {
+			continue
+		}
+		key, value, ok := strings.Cut(line, "=")
+		if !ok {
+			continue
+		}
+		key = strings.TrimSpace(key)
+		if _, exists := os.LookupEnv(key); exists {
+			continue
+		}
+		os.Setenv(key, strings.TrimSpace(value))
+	}
+	return scanner.Err()
+}
+
 func main() {
-	if err := godotenv.Load(); err != nil {
+	if err := loadEnvFile(".env"); err != nil {
 		log.Println("No .env file found")
 	}
 

go.mod

@@ -3,7 +3,6 @@ module go-backend
 go 1.24.1
 
 require (
-	github.com/joho/godotenv v1.5.1
 	github.com/lib/pq v1.10.9
 	golang.org/x/crypto v0.40.0
 )

go.sum

@@ -1,5 +1,3 @@
-github.com/joho/godotenv v1.5.1 h1:7eLL/+HRGLY0ldzfGMeQkb7vMd0as4CfYvUVzLqw0N0=
-github.com/joho/godotenv v1.5.1/go.mod h1:f4LDr5Voq0i2e/R5DDNOoa2zzDfwtkZa6DnEwAbqwq4=
 github.com/lib/pq v1.10.9 h1:YXG7RB+JIjhP29X+OtkiDnYaXQwpS4JEWq7dtCCRUEw=
 github.com/lib/pq v1.10.9/go.mod h1:AlVN5x4E4T544tWzH6hKfbfQvm3HdbOxrmggDNAPY9o=
 golang.org/x/crypto v0.40.0 h1:r4x+VvoG5Fm+eJcxMaY8CQM7Lb0l1lsmjGBQ6s8BfKM=