Implemented get_access_key_last_used

Written test that still does not work due to:
    ParamValidationError: Parameter validation failed:
    Unknown parameter in input: "UserName", must be one of: AccessKeyId
Refactored update_access_key and delete_access_key functions

IMPLEMENTATION_COVERAGE.md

@@ -2257,7 +2257,7 @@
 - [X] detach_user_policy
 - [X] enable_mfa_device
 - [ ] generate_credential_report
-- [ ] get_access_key_last_used
+- [X] get_access_key_last_used
 - [X] get_account_authorization_details
 - [ ] get_account_password_policy
 - [ ] get_account_summary

moto/iam/models.py

@@ -224,6 +224,10 @@ class AccessKey(BaseModel):
             datetime.utcnow(),
             "%Y-%m-%dT%H:%M:%SZ"
         )
+        self.last_used = datetime.strftime(
+            datetime.utcnow(),
+            "%Y-%m-%dT%H:%M:%SZ"
+        )
 
     def get_cfn_attribute(self, attribute_name):
         from moto.cloudformation.exceptions import UnformattedGetAttTemplateException
@@ -351,22 +355,25 @@ class User(BaseModel):
     def get_all_access_keys(self):
         return self.access_keys
 
+    def get_access_key_last_used(self, access_key_id):
+        key = self.get_access_key_by_id(access_key_id)
+        return key.last_used
+
     def delete_access_key(self, access_key_id):
-        for key in self.access_keys:
-            if key.access_key_id == access_key_id:
-                self.access_keys.remove(key)
-                break
-        else:
-            raise IAMNotFoundException(
-                "Key {0} not found".format(access_key_id))
+        key = self.get_access_key_by_id(access_key_id)
+        self.access_keys.remove(key)
 
     def update_access_key(self, access_key_id, status):
+        key = self.get_access_key_by_id(access_key_id)
+        key.status = status
+
+    def get_access_key_by_id(self, access_key_id):
         for key in self.access_keys:
             if key.access_key_id == access_key_id:
-                key.status = status
-                break
+                return key
         else:
-            raise IAMNotFoundException("The Access Key with id {0} cannot be found".format(access_key_id))
+            raise IAMNotFoundException(
+                "The Access Key with id {0} cannot be found".format(access_key_id))
 
     def get_cfn_attribute(self, attribute_name):
         from moto.cloudformation.exceptions import UnformattedGetAttTemplateException
@@ -838,6 +845,11 @@ class IAMBackend(BaseBackend):
         user = self.get_user(user_name)
         user.update_access_key(access_key_id, status)
 
+    def get_access_key_last_used(self, user_name, access_key_id):
+        user = self.get_user(user_name)
+        last_used = user.get_access_key_last_used(access_key_id)
+        return last_used
+
     def get_all_access_keys(self, user_name, marker=None, max_items=None):
         user = self.get_user(user_name)
         keys = user.get_all_access_keys()

moto/iam/responses.py

@@ -454,6 +454,13 @@ class IamResponse(BaseResponse):
         template = self.response_template(GENERIC_EMPTY_TEMPLATE)
         return template.render(name='UpdateAccessKey')
 
+    def get_access_key_last_used(self):
+        user_name = self._get_param('UserName')
+        access_key_id = self._get_param('AccessKeyId')
+        iam_backend.get_access_key_last_used(user_name, access_key_id)
+        template = self.response_template(GENERIC_EMPTY_TEMPLATE)
+        return template.render(name='GetAccessKeyLastUsed')
+
     def list_access_keys(self):
         user_name = self._get_param('UserName')
 

tests/test_iam/test_iam.py

@@ -695,6 +695,19 @@ def test_update_access_key():
     resp['AccessKeyMetadata'][0]['Status'].should.equal('Inactive')
 
 
+@mock_iam
+def test_get_access_key_last_used():
+    iam = boto3.resource('iam', region_name='us-east-1')
+    client = iam.meta.client
+    username = 'test-user'
+    iam.create_user(UserName=username)
+    with assert_raises(ClientError):
+        client.get_access_key_last_used(UserName=username, AccessKeyId='non-existent-key')
+    key = client.create_access_key(UserName=username)['AccessKey']
+    resp = client.get_access_key_last_used(UserName=username, AccessKeyId=key['AccessKeyId'])
+    resp.should.equal(key.last_used)
+
+
 @mock_iam
 def test_get_account_authorization_details():
     import json