Policy

An Identity and Access Management (IAM) policy, which specifies access controls for Google Cloud resources.

A Policy is a collection of bindings. A binding binds one or more members, or principals, to a single role. Principals can be user accounts, service accounts, Google groups, and domains (such as G Suite). A role is a named list of permissions; each role can be an IAM predefined role or a user-created custom role.

For some types of Google Cloud resources, a binding can also specify a condition, which is a logical expression that allows access to a resource only if the expression evaluates to true. A condition can add constraints based on attributes of the request, the resource, or both. To learn which resources support conditions in their IAM policies, see the IAM documentation.

JSON example:

    {
      "bindings": [
        {
          "role": "roles/resourcemanager.organizationAdmin",
          "members": [
            "user:mike@example.com",
            "group:admins@example.com",
            "domain:google.com",
            "serviceAccount:my-project-id@appspot.gserviceaccount.com"
          ]
        },
        {
          "role": "roles/resourcemanager.organizationViewer",
          "members": [
            "user:eve@example.com"
          ],
          "condition": {
            "title": "expirable access",
            "description": "Does not grant access after Sep 2020",
            "expression": "request.time < timestamp('2020-10-01T00:00:00.000Z')",
          }
        }
      ],
      "etag": "BwWWja0YfJA=",
      "version": 3
    }

YAML example:

    bindings:
    - members:
      - user:mike@example.com
      - group:admins@example.com
      - domain:google.com
      - serviceAccount:my-project-id@appspot.gserviceaccount.com
      role: roles/resourcemanager.organizationAdmin
    - members:
      - user:eve@example.com
      role: roles/resourcemanager.organizationViewer
      condition:
        title: expirable access
        description: Does not grant access after Sep 2020
        expression: request.time < timestamp('2020-10-01T00:00:00.000Z')
    etag: BwWWja0YfJA=
    version: 3

For a description of IAM and its features, see the IAM documentation.

JSON representation
{
  "version": integer,
  "bindings": [
    {
      object (Binding)
    }
  ],
  "etag": string
}
Fields
version

integer

Specifies the format of the policy.

Valid values are 0, 1, and 3. Requests that specify an invalid value are rejected.

Any operation that affects conditional role bindings must specify version 3. This requirement applies to the following operations:

  • Getting a policy that includes a conditional role binding
  • Adding a conditional role binding to a policy
  • Changing a conditional role binding in a policy
  • Removing any role binding, with or without a condition, from a policy that includes conditions

Important: If you use IAM Conditions, you must include the etag field whenever you call setIamPolicy. If you omit this field, then IAM allows you to overwrite a version 3 policy with a version 1 policy, and all of the conditions in the version 3 policy are lost.

If a policy does not include any conditions, operations on that policy may specify any valid version or leave the field unset.

To learn which resources support conditions in their IAM policies, see the IAM documentation.

bindings[]

object (Binding)

Associates a list of members, or principals, with a role. Optionally, may specify a condition that determines how and when the bindings are applied. Each of the bindings must contain at least one principal.

The bindings in a Policy can refer to up to 1,500 principals; up to 250 of these principals can be Google groups. Each occurrence of a principal counts towards these limits. For example, if the bindings grant 50 different roles to user:alice@example.com, and not to any other principal, then you can add another 1,450 principals to the bindings in the Policy.

etag

string (bytes format)

etag is used for optimistic concurrency control as a way to help prevent simultaneous updates of a policy from overwriting each other. It is strongly suggested that systems make use of the etag in the read-modify-write cycle to perform policy updates in order to avoid race conditions: An etag is returned in the response to getIamPolicy, and systems are expected to put that etag in the request to setIamPolicy to ensure that their change will be applied to the same version of the policy.

Important: If you use IAM Conditions, you must include the etag field whenever you call setIamPolicy. If you omit this field, then IAM allows you to overwrite a version 3 policy with a version 1 policy, and all of the conditions in the version 3 policy are lost.

A base64-encoded string.

Binding

Associates members, or principals, with a role.

JSON representation
{
  "role": string,
  "members": [
    string
  ],
  "condition": {
    object (Expr)
  }
}
Fields
role

string

Role that is assigned to the list of members, or principals. For example, roles/viewer, roles/editor, or roles/owner.

For an overview of the IAM roles and permissions, see the IAM documentation. For a list of the available pre-defined roles, see here.

members[]

string

Specifies the principals requesting access for a Google Cloud resource. members can have the following values:

  • allUsers: A special identifier that represents anyone who is on the internet; with or without a Google account.

  • allAuthenticatedUsers: A special identifier that represents anyone who is authenticated with a Google account or a service account. Does not include identities that come from external identity providers (IdPs) through identity federation.

  • user:{emailid}: An email address that represents a specific Google account. For example, alice@example.com .

  • serviceAccount:{emailid}: An email address that represents a Google service account. For example, my-other-app@appspot.gserviceaccount.com.

  • serviceAccount:{projectid}.svc.id.goog[{namespace}/{kubernetes-sa}]: An identifier for a Kubernetes service account. For example, my-project.svc.id.goog[my-namespace/my-kubernetes-sa].

  • group:{emailid}: An email address that represents a Google group. For example, admins@example.com.

  • domain:{domain}: The G Suite domain (primary) that represents all the users of that domain. For example, google.com or example.com.
  • principal://iam.googleapis.com/locations/global/workforcePools/{pool_id}/subject/{subject_attribute_value}: A single identity in a workforce identity pool.

  • principalSet://iam.googleapis.com/locations/global/workforcePools/{pool_id}/group/{groupId}: All workforce identities in a group.

  • principalSet://iam.googleapis.com/locations/global/workforcePools/{pool_id}/attribute.{attribute_name}/{attribute_value}: All workforce identities with a specific attribute value.

  • principalSet://iam.googleapis.com/locations/global/workforcePools/{pool_id}/*: All identities in a workforce identity pool.

  • principal://iam.googleapis.com/projects/{projectNumber}/locations/global/workloadIdentityPools/{pool_id}/subject/{subject_attribute_value}: A single identity in a workload identity pool.

  • principalSet://iam.googleapis.com/projects/{projectNumber}/locations/global/workloadIdentityPools/{pool_id}/group/{groupId}: A workload identity pool group.

  • principalSet://iam.googleapis.com/projects/{projectNumber}/locations/global/workloadIdentityPools/{pool_id}/attribute.{attribute_name}/{attribute_value}: All identities in a workload identity pool with a certain attribute.

  • principalSet://iam.googleapis.com/projects/{projectNumber}/locations/global/workloadIdentityPools/{pool_id}/*: All identities in a workload identity pool.

  • deleted:user:{emailid}?uid={uniqueid}: An email address (plus unique identifier) representing a user that has been recently deleted. For example, alice@example.com?uid=123456789012345678901. If the user is recovered, this value reverts to user:{emailid} and the recovered user retains the role in the binding.

  • deleted:serviceAccount:{emailid}?uid={uniqueid}: An email address (plus unique identifier) representing a service account that has been recently deleted. For example, my-other-app@appspot.gserviceaccount.com?uid=123456789012345678901. If the service account is undeleted, this value reverts to serviceAccount:{emailid} and the undeleted service account retains the role in the binding.

  • deleted:group:{emailid}?uid={uniqueid}: An email address (plus unique identifier) representing a Google group that has been recently deleted. For example, admins@example.com?uid=123456789012345678901. If the group is recovered, this value reverts to group:{emailid} and the recovered group retains the role in the binding.

  • deleted:principal://iam.googleapis.com/locations/global/workforcePools/{pool_id}/subject/{subject_attribute_value}: Deleted single identity in a workforce identity pool. For example, deleted:principal://iam.googleapis.com/locations/global/workforcePools/my-pool-id/subject/my-subject-attribute-value.

condition

object (Expr)

The condition that is associated with this binding.

If the condition evaluates to true, then this binding applies to the current request.

If the condition evaluates to false, then this binding does not apply to the current request. However, a different role binding might grant the same role to one or more of the principals in this binding.

To learn which resources support conditions in their IAM policies, see the IAM documentation.

Expr

Represents a textual expression in the Common Expression Language (CEL) syntax. CEL is a C-like expression language. The syntax and semantics of CEL are documented at https://github.com/google/cel-spec.

Example (Comparison):

title: "Summary size limit"
description: "Determines if a summary is less than 100 chars"
expression: "document.summary.size() < 100"

Example (Equality):

title: "Requestor is owner"
description: "Determines if requestor is the document owner"
expression: "document.owner == request.auth.claims.email"

Example (Logic):

title: "Public documents"
description: "Determine whether the document should be publicly visible"
expression: "document.type != 'private' && document.type != 'internal'"

Example (Data Manipulation):

title: "Notification string"
description: "Create a notification string with a timestamp."
expression: "'New message received at ' + string(document.create_time)"

The exact variables and functions that may be referenced within an expression are determined by the service that evaluates it. See the service documentation for additional information.

JSON representation
{
  "expression": string,
  "title": string,
  "description": string,
  "location": string
}
Fields
expression

string

Textual representation of an expression in Common Expression Language syntax.

title

string

Optional. Title for the expression, i.e. a short string describing its purpose. This can be used e.g. in UIs which allow to enter the expression.

description

string

Optional. Description of the expression. This is a longer text which describes the expression, e.g. when hovered over it in a UI.

location

string

Optional. String indicating the location of the expression for error reporting, e.g. a file name and a position in the file.