:doc:`CognitoIdentity <../../cognito-identity>` / Client / lookup_developer_identity

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lookup_developer_identity
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.. py:method:: CognitoIdentity.Client.lookup_developer_identity(**kwargs)

  

  Retrieves the ``IdentityID`` associated with a ``DeveloperUserIdentifier`` or the list of ``DeveloperUserIdentifier`` values associated with an ``IdentityId`` for an existing identity. Either ``IdentityID`` or ``DeveloperUserIdentifier`` must not be null. If you supply only one of these values, the other value will be searched in the database and returned as a part of the response. If you supply both, ``DeveloperUserIdentifier`` will be matched against ``IdentityID``. If the values are verified against the database, the response returns both values and is the same as the request. Otherwise, a ``ResourceConflictException`` is thrown.

   

  ``LookupDeveloperIdentity`` is intended for low-throughput control plane operations: for example, to enable customer service to locate an identity ID by username. If you are using it for higher-volume operations such as user authentication, your requests are likely to be throttled.  GetOpenIdTokenForDeveloperIdentity is a better option for higher-volume operations for user authentication.

   

  You must use Amazon Web Services developer credentials to call this operation.

  

  See also: `AWS API Documentation <https://docs.aws.amazon.com/goto/WebAPI/cognito-identity-2014-06-30/LookupDeveloperIdentity>`_  


  **Request Syntax**
  ::

    response = client.lookup_developer_identity(
        IdentityPoolId='string',
        IdentityId='string',
        DeveloperUserIdentifier='string',
        MaxResults=123,
        NextToken='string'
    )
    
  :type IdentityPoolId: string
  :param IdentityPoolId: **[REQUIRED]** 

    An identity pool ID in the format REGION:GUID.

    

  
  :type IdentityId: string
  :param IdentityId: 

    A unique identifier in the format REGION:GUID.

    

  
  :type DeveloperUserIdentifier: string
  :param DeveloperUserIdentifier: 

    A unique ID used by your backend authentication process to identify a user. Typically, a developer identity provider would issue many developer user identifiers, in keeping with the number of users.

    

  
  :type MaxResults: integer
  :param MaxResults: 

    The maximum number of identities to return.

    

  
  :type NextToken: string
  :param NextToken: 

    A pagination token. The first call you make will have ``NextToken`` set to null. After that the service will return ``NextToken`` values as needed. For example, let's say you make a request with ``MaxResults`` set to 10, and there are 20 matches in the database. The service will return a pagination token as a part of the response. This token can be used to call the API again and get results starting from the 11th match.

    

  
  
  :rtype: dict
  :returns: 
    
    **Response Syntax**

    
    ::

      {
          'IdentityId': 'string',
          'DeveloperUserIdentifierList': [
              'string',
          ],
          'NextToken': 'string'
      }
      
    **Response Structure**

    

    - *(dict) --* 

      Returned in response to a successful ``LookupDeveloperIdentity`` action.

      
      

      - **IdentityId** *(string) --* 

        A unique identifier in the format REGION:GUID.

        
      

      - **DeveloperUserIdentifierList** *(list) --* 

        This is the list of developer user identifiers associated with an identity ID. Cognito supports the association of multiple developer user identifiers with an identity ID.

        
        

        - *(string) --* 
    
      

      - **NextToken** *(string) --* 

        A pagination token. The first call you make will have ``NextToken`` set to null. After that the service will return ``NextToken`` values as needed. For example, let's say you make a request with ``MaxResults`` set to 10, and there are 20 matches in the database. The service will return a pagination token as a part of the response. This token can be used to call the API again and get results starting from the 11th match.

        
  
  **Exceptions**
  
  *   :py:class:`CognitoIdentity.Client.exceptions.InvalidParameterException`

  
  *   :py:class:`CognitoIdentity.Client.exceptions.ResourceNotFoundException`

  
  *   :py:class:`CognitoIdentity.Client.exceptions.NotAuthorizedException`

  
  *   :py:class:`CognitoIdentity.Client.exceptions.ResourceConflictException`

  
  *   :py:class:`CognitoIdentity.Client.exceptions.TooManyRequestsException`

  
  *   :py:class:`CognitoIdentity.Client.exceptions.InternalErrorException`

  