feat(backend): configurable log levels for troubleshooting

.config/example.yml

@@ -167,6 +167,17 @@ reservedUsernames: [
 # IP address family used for outgoing request (ipv4, ipv6 or dual)
 #outgoingAddressFamily: ipv4
 
+# Log Option
+# Production env: ['error', 'success', 'warning', 'info']
+# Debug/Test env or Troubleshooting: ['error', 'success', 'warning', 'debug' ,'info']
+# Production env which storage space or IO is tight: ['error', 'warning']
+logLevel: [
+  'error',
+  'success',
+  'warning',
+  'info'
+]
+
 # Syslog option
 #syslog:
 #  host: localhost

packages/backend/src/config/types.ts

@@ -89,6 +89,8 @@ export type Source = {
 	deliverJobMaxAttempts?: number;
 	inboxJobMaxAttempts?: number;
 
+	logLevel?: string[];
+
 	syslog: {
 		host: string;
 		port: number;

packages/backend/src/services/logger.ts

@@ -57,6 +57,7 @@ export default class Logger {
 		store = true,
 	): void {
 		if (envOption.quiet) return;
+		if (!(typeof config.logLevel === "undefined") && !config.logLevel.includes(level)) return;
 		if (!this.store) store = false;
 		if (level === "debug") store = false;
 
@@ -186,8 +187,9 @@ export default class Logger {
 		data?: Record<string, any> | null,
 		important = false,
 	): void {
-		// デバッグ用に使う(開発者に必要だが利用者に不要な情報)
-		if (process.env.NODE_ENV !== "production" || envOption.verbose) {
+		// Used for debugging (information necessary for developers but unnecessary for users)
+		// Fixed if statement is ignored when logLevel includes debug
+		if (config.logLevel?.includes("debug") || process.env.NODE_ENV !== "production" || envOption.verbose) {
 			this.log("debug", message, data, important);
 		}
 	}