chore(lambda): validate logLevel with JSON logFormat for advanced logging

Author: go-to-k

packages/aws-cdk-lib/aws-lambda/lib/function.ts

@@ -1077,6 +1077,10 @@ export class Function extends FunctionBase {
  * function and undefined if not.
  */
  private getLoggingConfig(props: FunctionProps): CfnFunction.LoggingConfigProperty | undefined {
+ if ((props.applicationLogLevel || props.systemLogLevel) && props.logFormat !== LogFormat.JSON) {
+ throw new Error('ApplicationLogLevel and SystemLogLevel cannot be specified without LogFormat being set to JSON.');
+ }
+
  let loggingConfig: CfnFunction.LoggingConfigProperty;
  if (props.logFormat || props.logGroup) {
  loggingConfig = {

packages/aws-cdk-lib/aws-lambda/test/logging-config.test.ts

@@ -133,6 +133,60 @@ describe('logging Config', () => {
  logGroupName: 'customLogGroup',
  }),
  });
- }).toThrowError('CDK does not support setting logRetention and logGroup');
+ }).toThrow(/CDK does not support setting logRetention and logGroup/);
+ });
+
+ test('Throws when applicationLogLevel is specified with TEXT logFormat', () => {
+ const app = new cdk.App();
+ const stack = new cdk.Stack(app, 'stack');
+ expect(() => {
+ new lambda.Function(stack, 'Lambda', {
+ code: new lambda.InlineCode('foo'),
+ handler: 'index.handler',
+ runtime: lambda.Runtime.NODEJS_18_X,
+ logFormat: lambda.LogFormat.TEXT,
+ applicationLogLevel: lambda.ApplicationLogLevel.INFO,
+ });
+ }).toThrow(/ApplicationLogLevel and SystemLogLevel cannot be specified without LogFormat being set to JSON./);
+ });
+
+ test('Throws when systemLogLevel is specified with TEXT logFormat', () => {
+ const app = new cdk.App();
+ const stack = new cdk.Stack(app, 'stack');
+ expect(() => {
+ new lambda.Function(stack, 'Lambda', {
+ code: new lambda.InlineCode('foo'),
+ handler: 'index.handler',
+ runtime: lambda.Runtime.NODEJS_18_X,
+ logFormat: lambda.LogFormat.TEXT,
+ systemLogLevel: lambda.SystemLogLevel.INFO,
+ });
+ }).toThrow(/ApplicationLogLevel and SystemLogLevel cannot be specified without LogFormat being set to JSON./);
+ });
+
+ test('Throws when applicationLogLevel is specified if logFormat is undefined', () => {
+ const app = new cdk.App();
+ const stack = new cdk.Stack(app, 'stack');
+ expect(() => {
+ new lambda.Function(stack, 'Lambda', {
+ code: new lambda.InlineCode('foo'),
+ handler: 'index.handler',
+ runtime: lambda.Runtime.NODEJS_18_X,
+ applicationLogLevel: lambda.ApplicationLogLevel.INFO,
+ });
+ }).toThrow(/ApplicationLogLevel and SystemLogLevel cannot be specified without LogFormat being set to JSON./);
+ });
+
+ test('Throws when systemLogLevel is specified if logFormat is undefined', () => {
+ const app = new cdk.App();
+ const stack = new cdk.Stack(app, 'stack');
+ expect(() => {
+ new lambda.Function(stack, 'Lambda', {
+ code: new lambda.InlineCode('foo'),
+ handler: 'index.handler',
+ runtime: lambda.Runtime.NODEJS_18_X,
+ systemLogLevel: lambda.SystemLogLevel.INFO,
+ });
+ }).toThrow(/ApplicationLogLevel and SystemLogLevel cannot be specified without LogFormat being set to JSON./);
  });
 });