Merge pull request #219 from apocelipes/feat-limit-worker-numbers

feat(server): Read default configs from environment variables

.travis.yml

@@ -7,6 +7,8 @@ python:
 - '3.7'
 - '3.8'
 install:
+- pip install -U importlib-metadata
+- pip list
 - pip install -r test-requirements.txt -U
 script:
 - echo $(git log -1 --pretty=%B) > latest_commit_msg; pre-commit run --hook-stage commit-msg commitlint --commit-msg-filename latest_commit_msg; rm -rf latest_commit_msg

CHANGELOG.md

@@ -4,6 +4,7 @@
 ## [Unreleased]
 ### Added
 - Added `post_ready` signal that will be sended after sea app is ready
+- Added reading default config from environment variables, will overwrite the config file
 
 ## [2.3.2] - 2022-01-12
 ### Changed

docs/configuration.md

@@ -7,6 +7,8 @@
 程序运行的时候，会根据 `SEA_ENV` 环境变量的值加载同名的 `configs` 子模块。需要注意:
 **配置名称不得包含小写字母，否则会被忽略。**
 
+**和配置文件中配置项同名的环境变量优先级更高，会覆盖配置文件中的值，例如环境变量`GRPC_WORKERS`将覆盖配置文件中的GRPC_WORKERS。**
+
 ## 基本配置
 
 `DEBUG`

sea/__init__.py

@@ -28,6 +28,8 @@ def create_app(root_path=None):
     app_class = import_string("app:App")
     _app = app_class(root_path, env=env)
     _app.config.from_object(config)
+    # only filter default configurations
+    _app.config.load_config_from_env()
 
     _app.load_middlewares()
     _app.load_extensions_in_module(import_string("app.extensions"))

sea/config.py

@@ -1,4 +1,8 @@
+import numbers
+import os
+
 from sea.datatypes import ConstantsObject
+from sea.utils import strtobool
 
 
 class ConfigAttribute:
@@ -45,5 +49,23 @@ def get_namespace(self, namespace, lowercase=True, trim_namespace=True):
             rv[key] = v
         return ConstantsObject(rv)
 
+    def load_config_from_env(self):
+        """
+        read environment variables and overwrite same name key's values.
+        `True` will be converted to python's bool `True`.
+        `1` will be converted to python's int `1`.
+        """
+        keys = self.keys()
+
+        for k in keys:
+            env_value = os.getenv(k)
+            if not env_value:
+                continue
+            value_type = type(self[k])
+            if value_type is bool:
+                self[k] = strtobool(env_value)
+            elif isinstance(env_value, (str, numbers.Number)):
+                self[k] = value_type(env_value)
+
     def __repr__(self):
         return '<%s %s>' % (self.__class__.__name__, dict.__repr__(self))

sea/utils.py

@@ -67,3 +67,19 @@ def logger_has_level_handler(logger):
         current = current.parent
 
     return False
+
+
+def strtobool(val):
+    """Convert a string representation of truth to true (1) or false (0).
+
+    True values are 'y', 'yes', 't', 'true', 'on', and '1'; false values
+    are 'n', 'no', 'f', 'false', 'off', and '0'.  Raises ValueError if
+    'val' is anything else.
+    """
+    val = val.lower()
+    if val in ('y', 'yes', 't', 'true', 'on', '1'):
+        return True
+    elif val in ('n', 'no', 'f', 'false', 'off', '0'):
+        return False
+    else:
+        raise ValueError("invalid truth value %r" % (val,))

tests/test_app.py

@@ -20,6 +20,10 @@ def test_baseapp(caplog):
     from configs import testing
 
     _app.config.from_object(testing)
+    assert _app.config["PORT"] == 4000
+    os.environ["PORT"] = "4001"
+    _app.config.load_config_from_env()
+    assert _app.config["PORT"] == 4001
     assert _app.debug
     assert _app.testing
     _app.load_middlewares()

tests/test_config.py

@@ -1,4 +1,5 @@
 import json
+import os
 
 from sea.config import ConfigAttribute, Config
 
@@ -29,6 +30,26 @@ class Test(Base):
     assert '<Config' in s
 
 
+def test_config_load_from_env():
+    config = Config('.', {'KEY_INT': 1, 'KEY_STR': 'str', 'KEY_BOOL': True})
+    os.environ['KEY_INT'] = "300"
+    os.environ['KEY_STR'] = "TESTING"
+    os.environ['KEY_BOOL'] = "False"
+
+    assert config['KEY_INT'] == 1
+    assert config['KEY_STR'] == 'str'
+    assert config['KEY_BOOL'] == True  # noqa
+
+    config.load_config_from_env()
+    assert config['KEY_INT'] == 300
+    assert config['KEY_STR'] == 'TESTING'
+    assert config['KEY_BOOL'] == False  # noqa
+
+    os.environ['TEST'] = 'True'
+    config.load_config_from_env()
+    assert 'TEST' not in config
+
+
 def test_config_attribute():
     class App:
         x = ConfigAttribute('n_x', json.loads)

tests/wd/configs/testing.py

@@ -3,3 +3,4 @@
 
 TESTING = True
 DEBUG = True
+PORT = 4000