remove dependence and implmented import_string

sanic/config.py

@@ -1,10 +1,8 @@
 import os
 import types
 
-import import_string
-
 from sanic.exceptions import PyFileError
-
+from sanic.helpers import import_string
 
 SANIC_PREFIX = "SANIC_"
 

sanic/helpers.py

@@ -1,4 +1,5 @@
 """Defines basics of HTTP standard."""
+from importlib import import_module
 
 STATUS_CODES = {
     100: b"Continue",
@@ -131,3 +132,9 @@ def remove_entity_headers(headers, allowed=("content-location", "expires")):
         if not is_entity_header(header) or header.lower() in allowed
     }
     return headers
+
+
+def import_string(module_name):
+    module, obj = module_name.rsplit('.', 1)
+    module = import_module(module)
+    return getattr(module, obj)()

setup.py

@@ -63,7 +63,6 @@ requirements = [
     'aiofiles>=0.3.0',
     'websockets>=6.0,<7.0',
     'multidict>=4.0,<5.0',
-    'import-string>=0.1.0'
 ]
 if strtobool(os.environ.get("SANIC_NO_UJSON", "no")):
     print("Installing without uJSON")

tests/test_config.py

@@ -35,6 +35,11 @@ def test_load_from_object_string(app):
     assert 'not_for_config' not in app.config
 
 
+def test_load_from_object_string_exception(app):
+    with pytest.raises(ImportError):
+        app.config.from_object('test_config.Config.test')
+
+
 def test_auto_load_env():
     environ["SANIC_TEST_ANSWER"] = "42"
     app = Sanic()

tests/test_helpers.py

@@ -1,4 +1,5 @@
 from sanic import helpers
+import pytest
 
 
 def test_has_message_body():
@@ -72,3 +73,14 @@ def test_remove_entity_headers():
 
     for header, expected in tests:
         assert helpers.remove_entity_headers(header) == expected
+
+
+def test_import_string():
+    from sanic.config import Config
+    obj = helpers.import_string('sanic.config.Config')
+    assert isinstance(obj, Config)
+
+
+def test_import_string_exception():
+    with pytest.raises(ImportError):
+        helpers.import_string('test.test.test')