2-s3.ts

private static createS3Bucket(scope: cdk.Construct, user: iam.User): s3.Bucket {
    const name = 'bucket';

    const bucket = new s3.Bucket(scope, name, {
        bucketName: name,
        accessControl: s3.BucketAccessControl.PUBLIC_READ,
        cors: [{
            allowedOrigins: [ '*' ],
            allowedMethods: [ s3.HttpMethods.GET ],
            allowedHeaders: [ '*' ]
        }]
    });

    bucket.grantWrite(user);

    return bucket;
}