Google Cloud Spanner Instance IAM

This page shows how to write Terraform for Cloud Spanner Instance IAM and write them securely.

google_spanner_instance_iam (Terraform)

The Instance IAM in Cloud Spanner can be configured in Terraform with the resource name google_spanner_instance_iam. The following sections describe how to use the resource and its parameters.

Example Usage from GitHub

An example could not be found in GitHub.

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The following arguments are supported:

  • instance - (Required) The name of the instance.

  • member/members - (Required) Identities that will be granted the privilege in role. Each entry can have one of 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.
    • user:[emailid]: An email address that represents a specific Google account. For example, or
    • serviceAccount:[emailid]: An email address that represents a service account. For example,
    • group:[emailid]: An email address that represents a Google group. For example,
    • domain:[domain]: A G Suite domain (primary, instead of alias) name that represents all the users of that domain. For example, or
  • role - (Required) The role that should be applied. Only one google_spanner_instance_iam_binding can be used per role. Note that custom roles must be of the format [projects|organizations]/[parent-name]/roles/[role-name].

  • policy_data - (Required only by google_spanner_instance_iam_policy) The policy data generated by a google_iam_policy data source.

  • project - (Optional) The ID of the project in which the resource belongs. If it is not provided, the provider project is used.

In addition to the arguments listed above, the following computed attributes are exported:

  • etag - (Computed) The etag of the instance's IAM policy.

Explanation in Terraform Registry

Three different resources help you manage your IAM policy for a Spanner instance. Each of these resources serves a different use case:

  • google_spanner_instance_iam_policy: Authoritative. Sets the IAM policy for the instance and replaces any existing policy already attached.

    Warning: It's entirely possibly to lock yourself out of your instance using google_spanner_instance_iam_policy. Any permissions granted by default will be removed unless you include them in your config.

  • google_spanner_instance_iam_binding: Authoritative for a given role. Updates the IAM policy to grant a role to a list of members. Other roles within the IAM policy for the instance are preserved.
  • google_spanner_instance_iam_member: Non-authoritative. Updates the IAM policy to grant a role to a new member. Other members for the role for the instance are preserved.

    Note: google_spanner_instance_iam_policy cannot be used in conjunction with google_spanner_instance_iam_binding and google_spanner_instance_iam_member or they will fight over what your policy should be.

    Note: google_spanner_instance_iam_binding resources can be used in conjunction with google_spanner_instance_iam_member resources only if they do not grant privilege to the same role.

Frequently asked questions

What is Google Cloud Spanner Instance IAM?

Google Cloud Spanner Instance IAM is a resource for Cloud Spanner of Google Cloud Platform. Settings can be wrote in Terraform.


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