fix: initializing KeycloakAdmin without server_url

According to the project readme, we could initialize a KeycloakAdmin object with a KeycloakOpenIDConnection object without other arguments but, server_url is required.

I made server_url optional and wrote a test for it.

src/keycloak/keycloak_admin.py

@@ -88,7 +88,7 @@ class KeycloakAdmin:
 
     def __init__(
             self,
-        server_url,
+            server_url=None,
             username=None,
             password=None,
             token=None,
@@ -815,7 +815,7 @@ class KeycloakAdmin:
         )
         raise_error_from_response(data_raw, KeycloakPostError, expected_codes=[201])
         _last_slash_idx = data_raw.headers["Location"].rindex("/")
-        return data_raw.headers["Location"][_last_slash_idx + 1 :]  # noqa: E203
+        return data_raw.headers["Location"][_last_slash_idx + 1:]  # noqa: E203
 
     def users_count(self, query=None):
         """Count users.
@@ -1339,7 +1339,7 @@ class KeycloakAdmin:
         )
         try:
             _last_slash_idx = data_raw.headers["Location"].rindex("/")
-            return data_raw.headers["Location"][_last_slash_idx + 1 :]  # noqa: E203
+            return data_raw.headers["Location"][_last_slash_idx + 1:]  # noqa: E203
         except KeyError:
             return
 
@@ -1965,7 +1965,7 @@ class KeycloakAdmin:
             data_raw, KeycloakPostError, expected_codes=[201], skip_exists=skip_exists
         )
         _last_slash_idx = data_raw.headers["Location"].rindex("/")
-        return data_raw.headers["Location"][_last_slash_idx + 1 :]  # noqa: E203
+        return data_raw.headers["Location"][_last_slash_idx + 1:]  # noqa: E203
 
     def update_client(self, client_id, payload):
         """Update a client.
@@ -2218,7 +2218,7 @@ class KeycloakAdmin:
             data_raw, KeycloakPostError, expected_codes=[201], skip_exists=skip_exists
         )
         _last_slash_idx = data_raw.headers["Location"].rindex("/")
-        return data_raw.headers["Location"][_last_slash_idx + 1 :]  # noqa: E203
+        return data_raw.headers["Location"][_last_slash_idx + 1:]  # noqa: E203
 
     def add_composite_client_roles_to_role(self, client_role_id, role_name, roles):
         """Add composite roles to client role.
@@ -2385,7 +2385,7 @@ class KeycloakAdmin:
             data_raw, KeycloakPostError, expected_codes=[201], skip_exists=skip_exists
         )
         _last_slash_idx = data_raw.headers["Location"].rindex("/")
-        return data_raw.headers["Location"][_last_slash_idx + 1 :]  # noqa: E203
+        return data_raw.headers["Location"][_last_slash_idx + 1:]  # noqa: E203
 
     def get_realm_role(self, role_name):
         """Get realm role by role name.
@@ -3281,7 +3281,7 @@ class KeycloakAdmin:
             data_raw, KeycloakPostError, expected_codes=[201], skip_exists=skip_exists
         )
         _last_slash_idx = data_raw.headers["Location"].rindex("/")
-        return data_raw.headers["Location"][_last_slash_idx + 1 :]  # noqa: E203
+        return data_raw.headers["Location"][_last_slash_idx + 1:]  # noqa: E203
 
     def update_client_scope(self, client_scope_id, payload):
         """Update a client scope.
@@ -3650,7 +3650,7 @@ class KeycloakAdmin:
         )
         raise_error_from_response(data_raw, KeycloakPostError, expected_codes=[201])
         _last_slash_idx = data_raw.headers["Location"].rindex("/")
-        return data_raw.headers["Location"][_last_slash_idx + 1 :]  # noqa: E203
+        return data_raw.headers["Location"][_last_slash_idx + 1:]  # noqa: E203
 
     def get_component(self, component_id):
         """Get representation of the component.

tests/test_keycloak_admin.py

@@ -19,6 +19,8 @@ from keycloak.exceptions import (
     KeycloakPutError,
 )
 
+from src.keycloak import KeycloakOpenIDConnection
+
 
 def test_keycloak_version():
     """Test version."""
@@ -111,6 +113,17 @@ def test_keycloak_admin_init(env):
             is None
     )
 
+    keycloak_connection = KeycloakOpenIDConnection(
+        server_url=f"http://{env.KEYCLOAK_HOST}:{env.KEYCLOAK_PORT}",
+        username=env.KEYCLOAK_ADMIN,
+        password=env.KEYCLOAK_ADMIN_PASSWORD,
+        realm_name="master",
+        client_id="admin-cli",
+        verify=True
+    )
+    keycloak_admin = KeycloakAdmin(connection=keycloak_connection)
+    assert keycloak_admin.token
+
 
 def test_realms(admin: KeycloakAdmin):
     """Test realms.