issue-3379 iam list_roles: implement PathPrefix, MaxItems and Marker (#3380)

* issue-3379 iam list_roles: implement PathPrefix, MaxItems and Marker

* issue-3379 fix cloudformation test

moto/iam/models.py

@@ -2011,16 +2011,23 @@ class IAMBackend(BaseBackend):
             user.name = new_user_name
             self.users[new_user_name] = self.users.pop(user_name)
 
-    def list_roles(self, path_prefix, marker, max_items):
-        roles = None
-        try:
-            roles = self.roles.values()
-        except KeyError:
-            raise IAMNotFoundException(
-                "Users {0}, {1}, {2} not found".format(path_prefix, marker, max_items)
-            )
+    def list_roles(self, path_prefix=None, marker=None, max_items=None):
+        path_prefix = path_prefix if path_prefix else "/"
+        max_items = int(max_items) if max_items else 100
+        start_index = int(marker) if marker else 0
 
-        return roles
+        roles = self.roles.values()
+        roles = filter_items_with_path_prefix(path_prefix, roles)
+        sorted_roles = sorted(roles, key=lambda role: role.id)
+
+        roles_to_return = sorted_roles[start_index : start_index + max_items]
+
+        if len(sorted_roles) <= (start_index + max_items):
+            marker = None
+        else:
+            marker = str(start_index + max_items)
+
+        return roles_to_return, marker
 
     def upload_signing_certificate(self, user_name, body):
         user = self.get_user(user_name)

moto/iam/responses.py

@@ -133,7 +133,7 @@ class IamResponse(BaseResponse):
                             entity_users.append(user.name)
 
         elif entity == "Role":
-            roles = iam_backend.list_roles(path_prefix, marker, max_items)
+            roles, _ = iam_backend.list_roles(path_prefix, marker, max_items)
             if roles:
                 for role in roles:
                     for p in role.managed_policies:
@@ -156,7 +156,7 @@ class IamResponse(BaseResponse):
                         if p == policy_arn:
                             entity_users.append(user.name)
 
-            roles = iam_backend.list_roles(path_prefix, marker, max_items)
+            roles, _ = iam_backend.list_roles(path_prefix, marker, max_items)
             if roles:
                 for role in roles:
                     for p in role.managed_policies:
@@ -356,9 +356,13 @@ class IamResponse(BaseResponse):
         return template.render()
 
     def list_roles(self):
-        roles = iam_backend.get_roles()
+        path_prefix = self._get_param("PathPrefix", "/")
+        marker = self._get_param("Marker", "0")
+        max_items = self._get_param("MaxItems", 100)
+
+        roles, marker = iam_backend.list_roles(path_prefix, marker, max_items)
         template = self.response_template(LIST_ROLES_TEMPLATE)
-        return template.render(roles=roles)
+        return template.render(roles=roles, marker=marker)
 
     def list_instance_profiles(self):
         profiles = iam_backend.get_instance_profiles()
@@ -1379,7 +1383,10 @@ REMOVE_ROLE_FROM_INSTANCE_PROFILE_TEMPLATE = """<RemoveRoleFromInstanceProfileRe
 
 LIST_ROLES_TEMPLATE = """<ListRolesResponse xmlns="https://iam.amazonaws.com/doc/2010-05-08/">
   <ListRolesResult>
-    <IsTruncated>false</IsTruncated>
+    <IsTruncated>{{ 'true' if marker else 'false' }}</IsTruncated>
+    {% if marker %}
+    <Marker>{{ marker }}</Marker>
+    {% endif %}
     <Roles>
       {% for role in roles %}
       <member>

tests/test_cloudformation/test_cloudformation_stack_integration.py

@@ -870,7 +870,7 @@ def test_iam_roles():
                             }
                         ]
                     },
-                    "Path": "my-path",
+                    "Path": "/my-path/",
                     "Policies": [
                         {
                             "PolicyDocument": {
@@ -939,7 +939,7 @@ def test_iam_roles():
         # Role name is not specified, so randomly generated - can't check exact name
         if "with-path" in role.role_name:
             role_name_to_id["with-path"] = role.role_id
-            role.path.should.equal("my-path")
+            role.path.should.equal("/my-path/")
         else:
             role_name_to_id["no-path"] = role.role_id
             role.role_name.should.equal("my-role-no-path-name")

tests/test_iam/test_iam.py

@@ -155,13 +155,13 @@ def test_create_role_and_instance_profile():
     conn = boto.connect_iam()
     conn.create_instance_profile("my-profile", path="my-path")
     conn.create_role(
-        "my-role", assume_role_policy_document="some policy", path="my-path"
+        "my-role", assume_role_policy_document="some policy", path="/my-path/"
     )
 
     conn.add_role_to_instance_profile("my-profile", "my-role")
 
     role = conn.get_role("my-role")
-    role.path.should.equal("my-path")
+    role.path.should.equal("/my-path/")
     role.assume_role_policy_document.should.equal("some policy")
 
     profile = conn.get_instance_profile("my-profile")
@@ -3933,3 +3933,77 @@ def test_policy_config_client():
         )["BaseConfigurationItems"][0]["resourceName"]
         == policies[8]["name"]
     )
+
+
+@mock_iam()
+def test_list_roles_with_more_than_100_roles_no_max_items_defaults_to_100():
+    iam = boto3.client("iam", region_name="us-east-1")
+    for i in range(150):
+        iam.create_role(
+            RoleName="test_role_{}".format(i), AssumeRolePolicyDocument="some policy"
+        )
+    response = iam.list_roles()
+    roles = response["Roles"]
+
+    assert response["IsTruncated"] is True
+    assert len(roles) == 100
+
+
+@mock_iam()
+def test_list_roles_max_item_and_marker_values_adhered():
+    iam = boto3.client("iam", region_name="us-east-1")
+    for i in range(10):
+        iam.create_role(
+            RoleName="test_role_{}".format(i), AssumeRolePolicyDocument="some policy"
+        )
+    response = iam.list_roles(MaxItems=2)
+    roles = response["Roles"]
+
+    assert response["IsTruncated"] is True
+    assert len(roles) == 2
+
+    response = iam.list_roles(Marker=response["Marker"])
+    roles = response["Roles"]
+
+    assert response["IsTruncated"] is False
+    assert len(roles) == 8
+
+
+@mock_iam()
+def test_list_roles_path_prefix_value_adhered():
+    iam = boto3.client("iam", region_name="us-east-1")
+    iam.create_role(
+        RoleName="test_role_without_path", AssumeRolePolicyDocument="some policy"
+    )
+    iam.create_role(
+        RoleName="test_role_with_path",
+        AssumeRolePolicyDocument="some policy",
+        Path="/TestPath/",
+    )
+
+    response = iam.list_roles(PathPrefix="/TestPath/")
+    roles = response["Roles"]
+
+    assert len(roles) == 1
+    assert roles[0]["RoleName"] == "test_role_with_path"
+
+
+@mock_iam()
+def test_list_roles_none_found_returns_empty_list():
+    iam = boto3.client("iam", region_name="us-east-1")
+
+    response = iam.list_roles()
+    roles = response["Roles"]
+    assert len(roles) == 0
+
+    response = iam.list_roles(PathPrefix="/TestPath")
+    roles = response["Roles"]
+    assert len(roles) == 0
+
+    response = iam.list_roles(Marker="10")
+    roles = response["Roles"]
+    assert len(roles) == 0
+
+    response = iam.list_roles(MaxItems=10)
+    roles = response["Roles"]
+    assert len(roles) == 0