Grant access to individual Cloud Workstations ports

You can use IAM Conditions to grant access to individual workstation ports. This is useful for sharing limited access to individual workstation ports. For example, you can use IAM Conditions to grant access to a demo server running on a workstation port.

Cloud Workstations supports destination.port IAM Conditions attribute.

For more information about IAM Conditions, see the following:

Before you begin

Before you can grant access to individual workstation ports, you must have the Cloud Workstations Policy Admin (roles/workstations.policyAdmin) role on the workstation.

Check IAM roles on the workstation

Be sure that you have the Cloud Workstations User (roles/workstations.user) and Cloud Workstations Policy Admin (roles/workstations.policyAdmin) roles on the workstation. If you don't, ask your organization's Cloud Workstations Admin to grant you those roles on the workstation.

Start a demo server in workstation

Start and connect to your workstations using the Launch workstation guide. Run the following command on the workstation to start a demo server on a workstation port.

python3 -m http.server WORKSTATIONS_PORT

Replace the following:

WORKSTATIONS_PORT: the port on which the demo server will listen. For example, use 8081.

Update conditional IAM policy of workstation

To grant access to a workstation port, you can use Google Cloud console or gcloud CLI iam policies command.

Console

To grant conditional access to the workstation:

In the Google Cloud console, navigate to the Cloud Workstations > Workstations page.
Go to Workstations
Find your workstation and then click themore_vertMore options menu, and select Add Users.
To grant conditional access, enter the email for the principal. For example, 222larabrown@gmail.com.
Ensure Cloud Workstations User is selected as a Role.
Update the IAM condition to grant port-specific access:
1. Click Add IAM Condition.
2. Specify a title such as Port WORKSTATIONS_PORT.
3. In the Condition Editor tab, enter the following condition:
```
destination.port == WORKSTATIONS_PORT
```
1. Click Save to finalize granting conditional access to the specific port to the principal.

gcloud

Get the workstation IAM policy by using the gcloud CLI workstations get-iam-policy command. This command outputs the policy to the file: /tmp/WORKSTATIONS_NAME.yaml. If the file exists, it will be overwritten.
```
gcloud workstations get-iam-policy WORKSTATIONS_NAME \
  --cluster=WORKSTATIONS_CLUSTER_NAME \
  --config=WORKSTATIONS_CONFIG_NAME \
  --region=LOCATION \
  --project=WORKSTATIONS_PROJECT_ID \
  > /tmp/WORKSTATIONS_NAME.yaml
```
Replace the following:
- WORKSTATIONS_NAME: the name of the workstation.
- WORKSTATIONS_CONFIG_NAME: the name of the workstation configuration.
- WORKSTATIONS_CLUSTER_NAME: the name of the workstation cluster.
- LOCATION: the region name for your workstation cluster.
- WORKSTATIONS_PROJECT_ID: the ID of the Cloud Workstations project containing your workstation.
The YAML format of the policy is downloaded into /tmp/WORKSTATIONS_NAME.yaml:
```
bindings:
- members:
  - user:222larabrown@gmail.com
  role: roles/workstations.user
etag: BwYdnV9Eg7Y=
version: 1
```
To grant conditional access to a principal, add the following highlighted condition expression to the policy file that you downloaded in the previous step.

Do not modify the etag. Ensure the version is specified as 3, since this policy includes the condition field.

For example:
```
bindings:
- members:
  - user:YOUR_ID
  role: roles/workstations.user
- condition:
    expression: destination.port == WORKSTATIONS_PORT
    title: Port WORKSTATIONS_PORT
  members:
  - user:PRINCIPAL
  role: roles/workstations.user
etag: BwYlui8uSXo=
version: 3
```
Replace the following:
- YOUR_ID: your own login ID. For example, 222larabrown@gmail.com.
- PRINCIPAL: the principal with whom you want share access of the port WORKSTATIONS_PORT of the workstation. For example, baklavainthebalkans@gmail.com.
- WORKSTATIONS_PORT: the workstation port on which the demo server is listening.
Set IAM policy of workstation using the gcloud CLI workstations set-iam-policy command.
```
gcloud workstations set-iam-policy WORKSTATIONS_NAME \
  --cluster=WORKSTATIONS_CLUSTER_NAME \
  --config=WORKSTATIONS_CONFIG_NAME \
  --region=LOCATION \
  --project=WORKSTATIONS_PROJECT_ID \
  /tmp/WORKSTATIONS_NAME.yaml
```
Replace the following:
- WORKSTATIONS_NAME: the name of the workstation.
- WORKSTATIONS_CONFIG_NAME: the name of the workstation configuration.
- WORKSTATIONS_CLUSTER_NAME: the name of the workstation cluster.
- LOCATION: the region name for your workstation cluster.
- WORKSTATIONS_PROJECT_ID: the ID of the Cloud Workstations project containing your workstation.

After the IAM policy of the workstation is updated, the principal will be able to access the specified port of the workstation.

Share URL of workstation

The principal will be able to access the specified port with the following workstation URL:

https://WORKSTATIONS_PORT-WORKSTATIONS_NAME.WORKSTATIONS_CLUSTER_NAME.cloudworkstations.dev

The placeholders represent the following:

WORKSTATIONS_PORT: the port on which the demo server is listening.
WORKSTATIONS_NAME: the workstation name.
WORKSTATIONS_CLUSTER_NAME: the randomly generated cluster identifier.
cloudworkstations.dev: the default domain name for a workstation.

The principal won't be able to access other ports of the workstation they don't have access to.