✨ Feature: 新增 dotenv 嵌套配置项支持 (#1324)

Co-authored-by: hemengyang <hmy0119@hotmail.com>

nonebot/config.py

@@ -14,14 +14,14 @@ from datetime import timedelta
 from ipaddress import IPv4Address
 from typing import TYPE_CHECKING, Any, Set, Dict, Tuple, Union, Mapping, Optional
 
-from pydantic import BaseSettings, IPvAnyAddress
+from pydantic.utils import deep_update
+from pydantic import Extra, BaseSettings, IPvAnyAddress
 from pydantic.env_settings import (
+    DotenvType,
     SettingsError,
     EnvSettingsSource,
     InitSettingsSource,
     SettingsSourceCallable,
-    read_env_file,
-    env_file_sentinel,
 )
 
 from nonebot.log import logger
@@ -32,33 +32,15 @@ class CustomEnvSettings(EnvSettingsSource):
         """
         Build environment variables suitable for passing to the Model.
         """
-        d: Dict[str, Optional[str]] = {}
+        d: Dict[str, Any] = {}
 
         if settings.__config__.case_sensitive:
             env_vars: Mapping[str, Optional[str]] = os.environ  # pragma: no cover
         else:
             env_vars = {k.lower(): v for k, v in os.environ.items()}
 
-        env_file_vars: Dict[str, Optional[str]] = {}
-        env_file = (
-            self.env_file
-            if self.env_file != env_file_sentinel
-            else settings.__config__.env_file
-        )
-        env_file_encoding = (
-            self.env_file_encoding
-            if self.env_file_encoding is not None
-            else settings.__config__.env_file_encoding
-        )
-        if env_file is not None:
-            env_path = Path(env_file)
-            if env_path.is_file():
-                env_file_vars = read_env_file(
-                    env_path,
-                    encoding=env_file_encoding,  # type: ignore
-                    case_sensitive=settings.__config__.case_sensitive,
-                )
-                env_vars = {**env_file_vars, **env_vars}
+        env_file_vars = self._read_env_files(settings.__config__.case_sensitive)
+        env_vars = {**env_file_vars, **env_vars}
 
         for field in settings.__fields__.values():
             env_val: Optional[str] = None
@@ -69,31 +51,56 @@ class CustomEnvSettings(EnvSettingsSource):
                 if env_val is not None:
                     break
 
-            if env_val is None:
-                continue
-
-            if field.is_complex():
-                try:
-                    env_val = settings.__config__.json_loads(env_val)
-                except ValueError as e:  # pragma: no cover
-                    raise SettingsError(
-                        f'error parsing JSON for "{env_name}"'  # type: ignore
-                    ) from e
-            d[field.alias] = env_val
-
-        if env_file_vars:
-            for env_name in env_file_vars.keys():
-                env_val = env_vars[env_name]
-                if env_val and (val_striped := env_val.strip()):
+            is_complex, allow_parse_failure = self.field_is_complex(field)
+            if is_complex:
+                if env_val is None:
+                    if env_val_built := self.explode_env_vars(field, env_vars):
+                        d[field.alias] = env_val_built
+                else:
+                    # field is complex and there's a value, decode that as JSON, then add explode_env_vars
                     try:
-                        env_val = settings.__config__.json_loads(val_striped)
+                        env_val = settings.__config__.parse_env_var(field.name, env_val)
                     except ValueError as e:
-                        logger.trace(
-                            "Error while parsing JSON for "
-                            f"{env_name!r}={val_striped!r}. "
-                            "Assumed as string."
-                        )
+                        if not allow_parse_failure:
+                            raise SettingsError(
+                                f'error parsing env var "{env_name}"'  # type: ignore
+                            ) from e
 
+                    if isinstance(env_val, dict):
+                        d[field.alias] = deep_update(
+                            env_val, self.explode_env_vars(field, env_vars)
+                        )
+                    else:
+                        d[field.alias] = env_val
+            elif env_val is not None:
+                # simplest case, field is not complex, we only need to add the value if it was found
+                d[field.alias] = env_val
+
+        # remain user custom config
+        for env_name in env_file_vars:
+            env_val = env_vars[env_name]
+            if env_val and (val_striped := env_val.strip()):
+                # there's a value, decode that as JSON
+                try:
+                    env_val = settings.__config__.parse_env_var(env_name, val_striped)
+                except ValueError as e:
+                    logger.trace(
+                        "Error while parsing JSON for "
+                        f"{env_name!r}={val_striped!r}. "
+                        "Assumed as string."
+                    )
+
+            # explode value when it's a nested dict
+            env_name, *nested_keys = env_name.split(self.env_nested_delimiter)
+            if nested_keys and (env_name not in d or isinstance(d[env_name], dict)):
+                result = {}
+                *keys, last_key = nested_keys
+                _tmp = result
+                for key in keys:
+                    _tmp = _tmp.setdefault(key, {})
+                _tmp[last_key] = env_val
+                d[env_name] = deep_update(d.get(env_name, {}), result)
+            elif not nested_keys:
                 d[env_name] = env_val
 
         return d
@@ -106,6 +113,9 @@ class BaseConfig(BaseSettings):
             return self.__dict__.get(name)
 
     class Config:
+        extra = Extra.allow
+        env_nested_delimiter = "__"
+
         @classmethod
         def customise_sources(
             cls,
@@ -117,7 +127,10 @@ class BaseConfig(BaseSettings):
             return (
                 init_settings,
                 CustomEnvSettings(
-                    env_settings.env_file, env_settings.env_file_encoding
+                    env_settings.env_file,
+                    env_settings.env_file_encoding,
+                    env_settings.env_nested_delimiter,
+                    env_settings.env_prefix_len,
                 ),
                 InitSettingsSource(common_config),
                 file_secret_settings,
@@ -137,7 +150,6 @@ class Env(BaseConfig):
     """
 
     class Config:
-        extra = "allow"
         env_file = ".env"
 
 
@@ -150,8 +162,7 @@ class Config(BaseConfig):
     配置方法参考: [配置](https://v2.nonebot.dev/docs/tutorial/configuration)
     """
 
-    _env_file: str = ".env"
-    _common_config: Dict[str, Any] = {}
+    _env_file: DotenvType = ".env", ".env.prod"
 
     # nonebot configs
     driver: str = "~fastapi"
@@ -231,8 +242,7 @@ class Config(BaseConfig):
     # or from env file using json loads
 
     class Config:
-        extra = "allow"
-        env_file = ".env.prod"
+        env_file = ".env", ".env.prod"
 
 
 __autodoc__ = {