diff --git a/packages/@aws-cdk/aws-ec2/lib/cfn-init-elements.ts b/packages/@aws-cdk/aws-ec2/lib/cfn-init-elements.ts index a190c17d7aa20..646d6b2dcbfa4 100644 --- a/packages/@aws-cdk/aws-ec2/lib/cfn-init-elements.ts +++ b/packages/@aws-cdk/aws-ec2/lib/cfn-init-elements.ts @@ -327,6 +327,9 @@ export abstract class InitFile extends InitElement { * Use a literal string as the file content */ public static fromString(fileName: string, content: string, options: InitFileOptions = {}): InitFile { + if (!content) { + throw new Error(`InitFile ${fileName}: cannot create empty file. Please supply at least one character of content.`); + } return new class extends InitFile { protected _doBind(bindOptions: InitBindOptions) { return { diff --git a/packages/@aws-cdk/aws-ec2/test/cfn-init-element.test.ts b/packages/@aws-cdk/aws-ec2/test/cfn-init-element.test.ts index e794021c46b8f..75896912f3661 100644 --- a/packages/@aws-cdk/aws-ec2/test/cfn-init-element.test.ts +++ b/packages/@aws-cdk/aws-ec2/test/cfn-init-element.test.ts @@ -206,6 +206,12 @@ describe('InitFile', () => { }); }); + test('empty content string throws error', () => { + expect(() => { + ec2.InitFile.fromString('/tmp/foo', ''); + }).toThrow('InitFile /tmp/foo: cannot create empty file. Please supply at least one character of content.'); + }); + test('symlink throws an error if mode is set incorrectly', () => { expect(() => { ec2.InitFile.symlink('/tmp/foo', '/tmp/bar', {