chg: add "override" load_dotenv() arg: set os.environ keys

current `load_dotenv()` functionality purely returns a validated dict;
this commit adds an `override` argument that functions like
`python-dotenv` to set the keys in `os.environ`

Author: tutankalex

nbs/00_core.ipynb

@@ -27,6 +27,7 @@
     "#| export\n",
     "from nbdev.showdoc import *\n",
     "from fastcore.test import *\n",
+    "from unittest.mock import patch\n",
     "\n",
     "import dotenv\n",
     "import json\n",
@@ -280,7 +281,18 @@
     "        return cls.load_validated_config(json_schema, dict(os.environ), **kwargs)\n",
     "        \n",
     "    @classmethod\n",
-    "    def load_dotenv(cls, json_schema: Union[str, dict]=None, dotenv_path: str=None, storage_driver: FS=None):\n",
+    "    def load_dotenv(cls,\n",
+    "                    json_schema: Union[str, dict]=None,\n",
+    "                    dotenv_path: str=None,\n",
+    "                    storage_driver: FS=None,\n",
+    "                    override: bool=False,\n",
+    "                   ):\n",
+    "        '''\n",
+    "        :param override: set variables into os.environ where applicable; i.e.\n",
+    "        - if set in os.environ already and valid, leave alone\n",
+    "        - if not set in os.environ already, read from .env or schema default\n",
+    "        '''\n",
+    "        \n",
     "        storage_driver = storage_driver or cls.DEFAULT_STORAGE_DRIVER\n",
     "        if dotenv_path is None:\n",
     "            maybe_dotenv_path = dotenv.find_dotenv()  # '' if not exist\n",
@@ -301,9 +313,17 @@
     "            if key in config and config[key] != os.environ[key]:\n",
     "                logger.debug(f'os.environ key \"{key}\" overriding value present in {dotenv_path}')\n",
     "            config[key] = os.environ[key]\n",
-    "        return cls.load_validated_config(\n",
+    "        validated_config = cls.load_validated_config(\n",
     "            json_schema or cls.get_default_json_schema(storage_driver=storage_driver),\n",
-    "            config, storage_driver=storage_driver)"
+    "            config, storage_driver=storage_driver)\n",
+    "        \n",
+    "        if override:\n",
+    "            for key, value in validated_config.items():\n",
+    "                if key in os.environ:\n",
+    "                    continue\n",
+    "                os.environ[key] = value\n",
+    "                \n",
+    "        return validated_config"
    ]
   },
   {
@@ -675,6 +695,84 @@
     "})"
    ]
   },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "#| hide\n",
+    "# test propagating values into os.environ depending on flag\n",
+    "\n",
+    "def test_propagate_values_into_os_environ():\n",
+    "    \n",
+    "    with memfs.open('flag.schema.json', 'w') as ofile:\n",
+    "        ofile.write(json.dumps({\n",
+    "            'type': 'object',\n",
+    "            'properties': {\n",
+    "                'UNINVITED_GUEST': { 'type': 'string', 'default': 'from schema' },\n",
+    "            }\n",
+    "        }))\n",
+    "    \n",
+    "    with memfs.open('.flag-env1', 'w') as ofile:\n",
+    "        ofile.write('')\n",
+    "    \n",
+    "    with memfs.open('.flag-env2', 'w') as ofile:\n",
+    "        ofile.write('\\n'.join([\n",
+    "            'UNINVITED_GUEST=from dotenv',\n",
+    "        ]))\n",
+    "    \n",
+    "    with memfs.open('.flag-env3', 'w') as ofile:\n",
+    "        ofile.write('\\n'.join([\n",
+    "            'UNINVITED_GUEST=I should be ignored!',\n",
+    "        ]))\n",
+    "\n",
+    "    mock_env = {\"already_here\": \"no touch me\"}\n",
+    "\n",
+    "    with patch.dict('os.environ', mock_env):\n",
+    "        \n",
+    "        # don't update os.environ\n",
+    "        validated_config1 = ConfigValidator.load_dotenv(\n",
+    "            json_schema='flag.schema.json',\n",
+    "            dotenv_path='.flag-env1',\n",
+    "            storage_driver=memfs,\n",
+    "        )\n",
+    "        test_eq(os.environ.get(\"already_here\"), \"no touch me\")\n",
+    "        test_eq(os.environ.get(\"UNINVITED_GUEST\"), None)\n",
+    "        test_eq(validated_config1.get(\"UNINVITED_GUEST\"), \"from schema\")\n",
+    "        \n",
+    "        # update os.environ, loading from schema\n",
+    "        validated_config2 = ConfigValidator.load_dotenv(\n",
+    "            json_schema='flag.schema.json',\n",
+    "            dotenv_path='.flag-env1',\n",
+    "            storage_driver=memfs,\n",
+    "            override=True\n",
+    "        )\n",
+    "        test_eq(validated_config1, validated_config2)\n",
+    "        test_eq(os.environ.get(\"UNINVITED_GUEST\"), \"from schema\")\n",
+    "        \n",
+    "        os.environ.pop('UNINVITED_GUEST')\n",
+    "        # update os.environ, loading from dotenv\n",
+    "        validated_config3 = ConfigValidator.load_dotenv(\n",
+    "            json_schema='flag.schema.json',\n",
+    "            dotenv_path='.flag-env2',\n",
+    "            storage_driver=memfs,\n",
+    "            override=True\n",
+    "        )\n",
+    "        test_eq(os.environ.get(\"UNINVITED_GUEST\"), \"from dotenv\")\n",
+    "        \n",
+    "        # os.environ is set; takes precedence\n",
+    "        validated_config3 = ConfigValidator.load_dotenv(\n",
+    "            json_schema='flag.schema.json',\n",
+    "            dotenv_path='.flag-env3',\n",
+    "            storage_driver=memfs,\n",
+    "            override=True\n",
+    "        )\n",
+    "        test_eq(os.environ.get(\"UNINVITED_GUEST\"), \"from dotenv\")\n",
+    "    \n",
+    "test_propagate_values_into_os_environ()"
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,

schematized_config/__init__.py

@@ -1 +1 @@
-__version__ = "0.0.6"
+__version__ = "0.0.7"

schematized_config/core.py

@@ -6,6 +6,7 @@
 # %% ../nbs/00_core.ipynb 2
 from nbdev.showdoc import *
 from fastcore.test import *
+from unittest.mock import patch
 
 import dotenv
 import json
@@ -157,7 +158,18 @@ def load_validated_environment(cls, json_schema: Union[str, dict]=None, **kwargs
         return cls.load_validated_config(json_schema, dict(os.environ), **kwargs)
 
     @classmethod
-    def load_dotenv(cls, json_schema: Union[str, dict]=None, dotenv_path: str=None, storage_driver: FS=None):
+    def load_dotenv(cls,
+                    json_schema: Union[str, dict]=None,
+                    dotenv_path: str=None,
+                    storage_driver: FS=None,
+                    override: bool=False,
+                   ):
+        '''
+        :param override: set variables into os.environ where applicable; i.e.
+        - if set in os.environ already and valid, leave alone
+        - if not set in os.environ already, read from .env or schema default
+        '''
+        
         storage_driver = storage_driver or cls.DEFAULT_STORAGE_DRIVER
         if dotenv_path is None:
             maybe_dotenv_path = dotenv.find_dotenv()  # '' if not exist
@@ -178,6 +190,14 @@ def load_dotenv(cls, json_schema: Union[str, dict]=None, dotenv_path: str=None,
             if key in config and config[key] != os.environ[key]:
                 logger.debug(f'os.environ key "{key}" overriding value present in {dotenv_path}')
             config[key] = os.environ[key]
-        return cls.load_validated_config(
+        validated_config = cls.load_validated_config(
             json_schema or cls.get_default_json_schema(storage_driver=storage_driver),
             config, storage_driver=storage_driver)
+        
+        if override:
+            for key, value in validated_config.items():
+                if key in os.environ:
+                    continue
+                os.environ[key] = value
+                
+        return validated_config

settings.ini

@@ -1,7 +1,7 @@
 [DEFAULT]
 repo = python-schematized-config
 lib_name = python-schematized-config
-version = 0.0.6
+version = 0.0.7
 min_python = 3.7
 license = apache2
 black_formatting = False