Struct Builder 

pub struct Builder { /* private fields */ }

Creates Credentials instances backed by the Metadata Service.

While the Google Cloud client libraries for Rust default to credentials backed by the metadata service, some applications may need to:

• Customize the metadata service credentials in some way
• Bypass the Application Default Credentials lookup and only use the metadata server credentials
• Use the credentials directly outside the client libraries

Implementations

impl Builder

pub fn with_endpoint<S: Into<String>>(self, endpoint: S) -> Self

Sets the endpoint for this credentials.

A trailing slash is significant, so specify the base URL without a trailing
slash. If not set, the credentials use http://metadata.google.internal.

Example

let credentials = Builder::default()
    .with_endpoint("https://metadata.google.foobar")
    .build();

pub fn with_quota_project_id<S: Into<String>>(self, quota_project_id: S) -> Self

Set the quota project for this credentials.

In some services, you can use a service account in one project for authentication and authorization, and charge the usage to a different project. This may require that the service account has serviceusage.services.use permissions on the quota project.

pub fn with_scopes<I, S>(self, scopes: I) -> Self

where I: IntoIterator<Item = S>, S: Into<String>,

Sets the scopes for this credentials.

Metadata server issues tokens based on the requested scopes. If no scopes are specified, the credentials defaults to all scopes configured for the default service account on the instance.

pub fn with_retry_policy<V: Into<RetryPolicyArg>>(self, v: V) -> Self

Configure the retry policy for fetching tokens.

The retry policy controls how to handle retries, and sets limits on the number of attempts or the total time spent retrying.

use gax::retry_policy::{AlwaysRetry, RetryPolicyExt};
let credentials = Builder::default()
    .with_retry_policy(AlwaysRetry.with_attempt_limit(3))
    .build();

pub fn with_backoff_policy<V: Into<BackoffPolicyArg>>(self, v: V) -> Self

Configure the retry backoff policy.

The backoff policy controls how long to wait in between retry attempts.

use gax::exponential_backoff::ExponentialBackoff;
let policy = ExponentialBackoff::default();
let credentials = Builder::default()
    .with_backoff_policy(policy)
    .build();

pub fn with_retry_throttler<V: Into<RetryThrottlerArg>>(self, v: V) -> Self

Configure the retry throttler.

Advanced applications may want to configure a retry throttler to Address Cascading Failures and when Handling Overload conditions. The authentication library throttles its retry loop, using a policy to control the throttling algorithm. Use this method to fine tune or customize the default retry throttler.

use gax::retry_throttler::AdaptiveThrottler;
let credentials = Builder::default()
    .with_retry_throttler(AdaptiveThrottler::default())
    .build();

pub fn build(self) -> Result<Credentials, Error>

Returns a Credentials instance with the configured settings.

pub fn build_access_token_credentials( self, ) -> Result<AccessTokenCredentials, Error>

Returns an AccessTokenCredentials instance with the configured settings.

Example

let credentials: AccessTokenCredentials = Builder::default()
    .with_quota_project_id("my-quota-project")
    .build_access_token_credentials()?;
let access_token = credentials.access_token().await?;
println!("Token: {}", access_token.token);

Trait Implementations

impl Debug for Builder

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Builder

fn default() -> Builder

Returns the “default value” for a type.