google.auth.credentials module

Interfaces for credentials.

class Credentials[source]

Bases: object

Base class for all credentials.

All credentials have a token that is used for authentication and may also optionally set an expiry to indicate when the token will no longer be valid.

Most credentials will be invalid until refresh() is called. Credentials can do this automatically before the first HTTP request in before_request().

Although the token and expiration will change as the credentials are refreshed and used, credentials should be considered immutable. Various credentials will accept configuration such as private keys, scopes, and other options. These options are not changeable after construction. Some classes will provide mechanisms to copy the credentials with modifications such as ScopedCredentials.with_scopes().

token = None

str – The bearer token that can be used in HTTP headers to make authenticated requests.

expiry = None

Optional [ datetime ] – When the token expires and is no longer valid. If this is None, the token is assumed to never expire.

expired

Checks if the credentials are expired.

Note that credentials can be invalid but not expired because Credentials with expiry set to None is considered to never expire.

valid

Checks the validity of the credentials.

This is True if the credentials have a token and the token is not expired.

refresh(request)[source]

Refreshes the access token.

Parameters:request (google.auth.transport.Request) – The object used to make HTTP requests.
Raises:google.auth.exceptions.RefreshError – If the credentials could not be refreshed.
apply(headers, token=None)[source]

Apply the token to the authentication header.

Parameters:
  • headers (Mapping) – The HTTP request headers.
  • token (Optional [ str ]) – If specified, overrides the current access token.
before_request(request, method, url, headers)[source]

Performs credential-specific before request logic.

Refreshes the credentials if necessary, then calls apply() to apply the token to the authentication header.

Parameters:
  • request (google.auth.transport.Request) – The object used to make HTTP requests.
  • method (str) – The request’s HTTP method or the RPC method being invoked.
  • url (str) – The request’s URI or the RPC service’s URI.
  • headers (Mapping) – The request’s headers.
class AnonymousCredentials[source]

Bases: google.auth.credentials.Credentials

Credentials that do not provide any authentication information.

These are useful in the case of services that support anonymous access or local service emulators that do not use credentials.

expired

Returns False, anonymous credentials never expire.

valid

Returns True, anonymous credentials are always valid.

refresh(request)[source]

Raises ValueError`, anonymous credentials cannot be refreshed.

apply(headers, token=None)[source]

Anonymous credentials do nothing to the request.

The optional token argument is not supported.

Raises:ValueError – If a token was specified.
before_request(request, method, url, headers)[source]

Anonymous credentials do nothing to the request.

class ReadOnlyScoped[source]

Bases: object

Interface for credentials whose scopes can be queried.

OAuth 2.0-based credentials allow limiting access using scopes as described in RFC6749 Section 3.3. If a credential class implements this interface then the credentials either use scopes in their implementation.

Some credentials require scopes in order to obtain a token. You can check if scoping is necessary with requires_scopes:

if credentials.requires_scopes:
    # Scoping is required.
    credentials = credentials.with_scopes(scopes=['one', 'two'])

Credentials that require scopes must either be constructed with scopes:

credentials = SomeScopedCredentials(scopes=['one', 'two'])

Or must copy an existing instance using with_scopes():

scoped_credentials = credentials.with_scopes(scopes=['one', 'two'])

Some credentials have scopes but do not allow or require scopes to be set, these credentials can be used as-is.

scopes

Sequence [ str ] – the credentials’ current set of scopes.

requires_scopes

True if these credentials require scopes to obtain an access token.

has_scopes(scopes)[source]

Checks if the credentials have the given scopes.

Parameters:scopes (Sequence [ str ]) – The list of scopes to check.
Returns:True if the credentials have the given scopes.
Return type:bool
class Scoped[source]

Bases: google.auth.credentials.ReadOnlyScoped

Interface for credentials whose scopes can be replaced while copying.

OAuth 2.0-based credentials allow limiting access using scopes as described in RFC6749 Section 3.3. If a credential class implements this interface then the credentials either use scopes in their implementation.

Some credentials require scopes in order to obtain a token. You can check if scoping is necessary with requires_scopes:

if credentials.requires_scopes:
    # Scoping is required.
    credentials = credentials.create_scoped(['one', 'two'])

Credentials that require scopes must either be constructed with scopes:

credentials = SomeScopedCredentials(scopes=['one', 'two'])

Or must copy an existing instance using with_scopes():

scoped_credentials = credentials.with_scopes(scopes=['one', 'two'])

Some credentials have scopes but do not allow or require scopes to be set, these credentials can be used as-is.

with_scopes(scopes)[source]

Create a copy of these credentials with the specified scopes.

Parameters:scopes (Sequence [ str ]) – The list of scopes to attach to the current credentials.
Raises:NotImplementedError – If the credentials’ scopes can not be changed. This can be avoided by checking requires_scopes before calling this method.
has_scopes(scopes)

Checks if the credentials have the given scopes.

Parameters:scopes (Sequence [ str ]) – The list of scopes to check.
Returns:True if the credentials have the given scopes.
Return type:bool
requires_scopes

True if these credentials require scopes to obtain an access token.

scopes

Sequence [ str ] – the credentials’ current set of scopes.

with_scopes_if_required(credentials, scopes)[source]

Creates a copy of the credentials with scopes if scoping is required.

This helper function is useful when you do not know (or care to know) the specific type of credentials you are using (such as when you use google.auth.default()). This function will call Scoped.with_scopes() if the credentials are scoped credentials and if the credentials require scoping. Otherwise, it will return the credentials as-is.

Parameters:
Returns:

Either a new set of scoped

credentials, or the passed in credentials instance if no scoping was required.

Return type:

google.auth.credentials.Credentials

class Signing[source]

Bases: object

Interface for credentials that can cryptographically sign messages.

sign_bytes(message)[source]

Signs the given message.

Parameters:message (bytes) – The message to sign.
Returns:The message’s cryptographic signature.
Return type:bytes
signer_email

Optional [ str ] – An email address that identifies the signer.

signer

google.auth.crypt.Signer – The signer used to sign bytes.