Cloud Storage ACLs
Cloud Storage provides separate access control in addition to IAM. There are two ways, in fact: a more uniform way of doing access control via IAM and a legacy way of doing access control via fine-grained ACLs. Object ACLs do not appear in the hierarchy of IAM policies, so be aware of how your Cloud Storage buckets are controlled. When evaluating who has access to one of your objects, make sure you check the ACLs for the object, in addition to checking your project- and bucket-level IAM policies. This could get very convoluted, so the recommendation is to use uniform access control using IAM in most cases.
Access Control Lists (ACLs)
You can use an ACL to determine who has access to your buckets and objects, as well as what level of access they have. ACLs are applied to specific buckets and objects in Cloud Storage. There are one or more entries in each ACL. An entry enables a certain user (or group) to carry out specific tasks. Each entry is made up of two...
