Set the quota project

This page describes how to set a quota project for your client-based APIs. For information about what the quota project is, how to set the quota API, and how the quota project is determined, see About the quota project.

When you make a request to a client-based API, if a quota project cannot be identified, the request fails.

The quota project can be set in multiple ways, and the project will be verified by checking the following options. The order listed is the order of their precedence.

  • The quota project set in the environment or in the request.
  • If you use an API key to provide credentials for a request, the project associated with the API key is used as the quota project.
  • If you use the Google Cloud CLI to get your access token, and you've authenticated to the gcloud CLI with your user credentials, the gcloud CLI shared project is sometimes used as the quota project. Not all client-based APIs fall back on the shared project.
  • If the principal for the API call is a service account, including by impersonation, the project associated with the service account is used as the quota project.
  • If the principal for the API is a workforce identity federation user, the workforce pools user project is used as the quota project.

If none of the above checks yield a quota project, the request fails.

There are several ways to set quota projects. If the quota project is specified by more than one method, the following precedence is applied:

  1. Programmatically
  2. Environment variable
  3. Credentials used to authenticate the request

Set the quota project programmatically

You can explicitly set the quota project in your application. This method overrides all other definitions. The principal used to authenticate the request must have the required permission on the specified quota project.

How you set the quota project programmatically depends on whether you're using a client library, gcloud CLI, or REST request.

Client library

You can set the value for the quota project by using client options when you create the client. This method works well if you want to control the value for your quota project from your application, regardless of what environment it's running in.

For more information about implementing client options, see your client library documentation.

gcloud CLI

You can set the quota project for all gcloud CLI commands by using the billing/quota_project property in your gcloud CLI configuration. You can also set the quota project for a specific command by using the --billing-project flag, which takes precedence over the configuration property.

For more information about gcloud CLI configurations, see the gcloud config reference page. For more information about the --billing-project flag, see the global flags reference.

REST request

You can specify the quota project in a REST request using the x-goog-user-project header. The principal making the request must have the required permissions on the quota project.

For more information and sample code, see Set the quota project with a REST request.

Set the quota project using an environment variable

Client libraries for some languages support setting the quota project using an environment variable. This approach can be helpful if you want to set the quota project differently in different shells, or to override the quota project associated with the credential. The principal for any request must have the required permissions on the quota project specified by the environment variable.

The environment variable is language dependent:

Language Environment variable
C++

GOOGLE_CLOUD_CPP_USER_PROJECT

C#

GOOGLE_CLOUD_QUOTA_PROJECT

Go

GOOGLE_CLOUD_QUOTA_PROJECT

Java

GOOGLE_CLOUD_QUOTA_PROJECT

Node.js

GOOGLE_CLOUD_QUOTA_PROJECT

Python

GOOGLE_CLOUD_QUOTA_PROJECT

PHP

GOOGLE_CLOUD_QUOTA_PROJECT

Ruby Not available

Set the quota project using authentication credentials

If the quota project isn't specified, the authentication libraries try to determine it from the credentials that were used for the request. This process depends on the type of credentials that were used to authenticate the request:

  • Service account – The project associated with the service account is used as the quota project.
  • User credentials – For a local development environment, Application Default Credentials finds your user credentials from the local ADC file. That file can also specify a quota project. If you have the project set in your Google Cloud CLI config, and you have the required permissions on that project, the quota project is set by default when you create the local ADC file. You can also set the ADC quota project by using the auth application-default set-quota-project command.
  • API keys – When you use an API key to provide credentials for a request, the project associated with the API key is used as the quota project.

Permission required to set and use the quota project

To get the permission that you need to set a project as the quota project, or use that quota project in a request, ask your administrator to grant you the Service Usage Consumer (roles/serviceusage.serviceUsageConsumer) IAM role on the project. For more information about granting roles, see Manage access.

This predefined role contains the serviceusage.services.use permission, which is required to set a project as the quota project, or use that quota project in a request.

You might also be able to get this permission with custom roles or other predefined roles.

If you use a project you created as your quota project, you have the necessary permissions.

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