Added redshift.get_cluster_credentials (#3611)

* Added redshift.get_cluster_credentials

* Marked endpoint in list

* Removed f string from tests

* Python 2.7 compat changes

* Fixed parameter retrieval

* Formatting

* Removed try/catch in favor of if

* Changed to existing random_string util

Co-authored-by: Andrea Amorosi <aamorosi@amazon.es>

moto/redshift/models.py

@@ -8,6 +8,7 @@ from boto3 import Session
 from moto.compat import OrderedDict
 from moto.core import BaseBackend, BaseModel, CloudFormationModel
 from moto.core.utils import iso_8601_datetime_with_milliseconds
+from moto.utilities.utils import random_string
 from moto.ec2 import ec2_backends
 from .exceptions import (
     ClusterAlreadyExistsFaultError,
@@ -941,6 +942,25 @@ class RedshiftBackend(BaseBackend):
         resource = self._get_resource_from_arn(resource_name)
         resource.delete_tags(tag_keys)
 
+    def get_cluster_credentials(
+        self, cluster_identifier, db_user, auto_create, duration_seconds
+    ):
+        if duration_seconds < 900 or duration_seconds > 3600:
+            raise InvalidParameterValueError(
+                "Token duration must be between 900 and 3600 seconds"
+            )
+        expiration = datetime.datetime.now() + datetime.timedelta(0, duration_seconds)
+        if cluster_identifier in self.clusters:
+            user_prefix = "IAM:" if auto_create is False else "IAMA:"
+            db_user = user_prefix + db_user
+            return {
+                "DbUser": db_user,
+                "DbPassword": random_string(32),
+                "Expiration": expiration,
+            }
+        else:
+            raise ClusterNotFoundError(cluster_identifier)
+
 
 redshift_backends = {}
 for region in Session().get_available_regions("redshift"):

moto/redshift/responses.py

@@ -694,3 +694,24 @@ class RedshiftResponse(BaseResponse):
                 }
             }
         )
+
+    def get_cluster_credentials(self):
+        cluster_identifier = self._get_param("ClusterIdentifier")
+        db_user = self._get_param("DbUser")
+        auto_create = self._get_bool_param("AutoCreate", False)
+        duration_seconds = self._get_int_param("DurationSeconds", 900)
+
+        cluster_credentials = self.redshift_backend.get_cluster_credentials(
+            cluster_identifier, db_user, auto_create, duration_seconds
+        )
+
+        return self.get_response(
+            {
+                "GetClusterCredentialsResponse": {
+                    "GetClusterCredentialsResult": cluster_credentials,
+                    "ResponseMetadata": {
+                        "RequestId": "384ac68d-3775-11df-8963-01868b7c937a"
+                    },
+                }
+            }
+        )