This article explains a bit of the "under the hood" workings that enable you to interact with GCP Storage and GCP Compute without directly interfacing with the Google Cloud Platform console. Most users don't need this level of detail for working in Terra, but if you need to grant access to data that is on Google Cloud but outside of a Terra workspace, read on...
Overview: How Terra interfaces with GCP
To maintain the high security required for working with controlled-access data in the cloud, Terra cannot use your user ID when interacting with cloud resources external to Terra. Instead, Terra creates and uses additional Google accounts (specific to you) called "pet service accounts." Terra also puts all of these "pet service accounts" into a convenient Google Group (specific to you) called a "Proxy Group."
Pet service accounts
In addition to the user account you have registered with Terra, you also have one or more service accounts that Terra creates for you. A service account is a special type of Google account that lets Terra interface directly with GCP on your behalf - so your workflows and notebooks can access your data in Google Cloud, for example.
Your pet service account has the format:
To manage these accounts and simplify access control, everyone registered in Terra has a unique group, called a "proxy group" that contains your registered user account and your service accounts. Your proxy group includes everything needed to grant access to cloud resources outside of Terra (such as a GCS bucket or BigQuery dataset) inside GCP console.
Your Proxy group has the format:
Finding your proxy group
1. On the upper left-hand side click on the menu button (three lines at the top of any page on Terra).
2. Next to your name, click the drop down arrow.
3. Click on the profile button under your name.
4. You'll see your proxy group listed near the bottom left.
Best Practices: Use a Terra group instead of a proxy
You can create a Terra group (with a sensible name) as a proxy for your proxy.
If your registered Terra account is
firstname.lastname@example.org, create a Terra Group named
j_doe_at_someplace_org. Don't add anyone else to this group. You can then make grants to
email@example.com. This group contains one member, the proxy group for
firstname.lastname@example.org. This is much easier for a human to reason over and recognize!
Why use a Terra group for external access? While it's necessary for accessing resources that exist outside of Terra, the pre-defined Proxy Group identifier is not very human-friendly. If you're looking at a list of users with access to an external GCS bucket, seeing that there's a grant to
PROXY_11564882405514439@firecloud.org is not helpful unless you happen to have a way to look up that Proxy Group.
Note that this approach extends to when you actually do want to make grants to groups of Terra users. It is better to add them all to a Terra group and then grant access to that group's firecloud.org Google Group.
Create your personal Terra group in four steps
1. Go to your Groups page ("Main menu" --> "Groups" from the top left of any page in Terra).
2. In the Create a New Group card, click on the blue + icon.
3. Enter your human-friendly user-ID (can be the same as your Terra login) and click the Create Group button.
Terra creates a mirrored Google group that includes your Proxy (which already includes your user ID). When you (or the owner/admin) grant access on a GCP resource to the <terra-group>@firecloud.org group, both your end-user credentials and your pet service accounts have access to the GCP resource.
4. To access external resources, owners can now grant permission to your Terra group (i.e. email@example.com) in GCP console.
Using "firstname.lastname@example.org," makes it easier to see who has access permissions!
Pro-tip: Granting permission to groups of Terra users You can extend this to groups of Terra users, by first setting up a group for each person's Terra proxy (following the steps above).
Then create a managed group (i.e.
your-lab-group) that includes all these personal groups.
To give permission to everyone in the group, you would grant access to
email@example.com. Since you can add or remove group members in the UI, it's easy to adjust who has access.
Want to learn more about how to access advanced GCP features (things not yet available in the Terra UI)? See Accessing GCP features that are not in the Terra UI.
- WRITE to BigQuery
- Interact with Cloud Storage buckets other than the workspace bucket
- Run dsub jobs
- Run Cloud Dataflow jobs
- Run Cloud ML engine jobs
For recommendations, see Best practices for accessing external resources (Google buckets, GCP VMs etc.).