feat: optional MySQL/MariaDB database driver for deployments that cannot use local SQLite

cmd/server/main.go

@@ -12,6 +12,7 @@ import (
 	"net/http"
 	"os"
 	"os/signal"
+	"slices"
 	"syscall"
 	"time"
 
@@ -44,6 +45,12 @@ var envDefaults = map[string]string{
 	"ENVIRONMENT":                    "production",
 	"PORT":                           "8080",
 	"DB_FILE":                        "./data/renewcms.db",
+	config.EnvDatabaseDriver:         config.DefaultDatabaseDriver,
+	"DB_PORT":                        config.DefaultDatabasePort,
+	"DB_TLS":                         config.DefaultDatabaseTLS,
+	"DB_MAX_OPEN_CONNS":              config.DefaultMaxOpenConns,
+	"DB_MAX_IDLE_CONNS":              config.DefaultMaxIdleConns,
+	"DB_CONN_MAX_LIFETIME_SECONDS":   config.DefaultConnMaxLifetimeSeconds,
 	"UPLOAD_DIR":                     "./data/uploads",
 	"AUTH_RATE_LIMIT_MAX_ATTEMPTS":   "5",
 	"AUTH_RATE_LIMIT_WINDOW_SECONDS": "60",
@@ -108,10 +115,9 @@ func applyEnvDefaults() {
 }
 
 func ensureRequiredEnvVars() {
-	for _, envVar := range requiredEnvVars {
-		if _, isSet := os.LookupEnv(envVar); !isSet {
-			panic(fmt.Sprintf("Environment variable %s is not set", envVar))
-		}
+	required := slices.Concat(requiredEnvVars, config.DatabaseRequiredEnvVars(os.Getenv(config.EnvDatabaseDriver)))
+	if err := config.MissingEnvVarError(required, os.LookupEnv); err != nil {
+		panic(err.Error())
 	}
 }