Fix #976 from envvars parse True/False as booleans (#983)

Only when reading from envvars True and False will be transformed to lowercase to allow toml parser.

docs/envvars.md

@@ -33,6 +33,12 @@ export DYNACONF_STRING_NUM="'76'"                            # str: "76"
 export DYNACONF_PERSON__IS_ADMIN=true                        # bool: True (nested)
 ```
 
+!!! info 
+    For envvars Dynaconf will automatically transform `True` and `False` to `true` and `false` respectively,
+    this transformation allows TOML to parse the value as a boolean.  
+    If you want to keep the original value in this case use `@str` or wrap it in quotes twice like `FOO='"True"'`
+    Note that this applies only for strictly string equal to `True|False` doesn't apply to same string found
+    inside toml data structures.
 
 With the above it is now possible to read the settings in your `program.py` using:
 

dynaconf/base.py

@@ -36,6 +36,7 @@
 from dynaconf.utils.functional import empty
 from dynaconf.utils.functional import LazyObject
 from dynaconf.utils.parse_conf import apply_converter
+from dynaconf.utils.parse_conf import boolean_fix
 from dynaconf.utils.parse_conf import converters
 from dynaconf.utils.parse_conf import Lazy
 from dynaconf.utils.parse_conf import parse_conf_data
@@ -157,7 +158,8 @@ def _should_load_dotenv(self):
         """Chicken and egg problem, we must manually check envvar
         before deciding if we are loading envvars :)"""
         _environ_load_dotenv = parse_conf_data(
-            os.environ.get("LOAD_DOTENV_FOR_DYNACONF"), tomlfy=True
+            boolean_fix(os.environ.get("LOAD_DOTENV_FOR_DYNACONF")),
+            tomlfy=True,
         )
         return self._kwargs.get("load_dotenv", _environ_load_dotenv)
 
@@ -498,7 +500,7 @@ def get(
                 sysenv_fallback, list
             ) and key in [upperfy(k) for k in sysenv_fallback]
             if sysenv_fallback is True or key_in_sysenv_fallback_list:
-                default = self.environ.get(key)
+                default = self.get_environ(key, cast=True)
 
         # default values should behave exactly Dynaconf parsed values
         if default is not None:
@@ -561,7 +563,9 @@ def get_environ(self, key, default=None, cast=None):
             if cast in converters:
                 data = apply_converter(cast, data, box_settings=self)
             elif cast is True:
-                data = parse_conf_data(data, tomlfy=True, box_settings=self)
+                data = parse_conf_data(
+                    boolean_fix(data), tomlfy=True, box_settings=self
+                )
         return data
 
     def exists_in_environ(self, key):

dynaconf/default_settings.py

@@ -9,6 +9,7 @@
 from dynaconf.utils import upperfy
 from dynaconf.utils import warn_deprecations
 from dynaconf.utils.files import find_file
+from dynaconf.utils.parse_conf import boolean_fix
 from dynaconf.utils.parse_conf import parse_conf_data
 from dynaconf.vendor.dotenv import load_dotenv
 
@@ -33,7 +34,7 @@ def get(key, default=None):
         value = try_renamed(key, value, old, new)
 
     return (
-        parse_conf_data(value, tomlfy=True, box_settings={})
+        parse_conf_data(boolean_fix(value), tomlfy=True, box_settings={})
         if value is not None
         else default
     )

dynaconf/loaders/env_loader.py

@@ -6,6 +6,7 @@
 from dynaconf.loaders.base import SourceMetadata
 from dynaconf.utils import missing
 from dynaconf.utils import upperfy
+from dynaconf.utils.parse_conf import boolean_fix
 from dynaconf.utils.parse_conf import parse_conf_data
 
 DOTENV_IMPORTED = False
@@ -75,14 +76,14 @@ def load_from_env(
             try:  # obj is a Settings
                 obj.set(
                     key,
-                    value,
+                    boolean_fix(value),
                     loader_identifier=source_metadata,
                     tomlfy=True,
                     validate=validate,
                 )
             except AttributeError:  # obj is a dict
                 obj[key] = parse_conf_data(
-                    value, tomlfy=True, box_settings=obj
+                    boolean_fix(value), tomlfy=True, box_settings=obj
                 )
 
     # Load environment variables in bulk (when matching).
@@ -94,9 +95,9 @@ def load_from_env(
         trim_len = len(env_)
         data = {
             key[trim_len:]: parse_conf_data(
-                data, tomlfy=True, box_settings=obj
+                boolean_fix(value), tomlfy=True, box_settings=obj
             )
-            for key, data in environ.items()
+            for key, value in environ.items()
             if key.startswith(env_)
             and not (
                 # Ignore environment variables that haven't been

dynaconf/utils/parse_conf.py

@@ -445,3 +445,17 @@ def unparse_conf_data(value):
         return "@none "
 
     return value
+
+
+def boolean_fix(value: str | None):
+    """Gets a value like `True/False` and turns to `true/false`
+    This function exists because of issue #976
+    Toml parser casts booleans from true/false lower case
+    however envvars are usually exportes as True/False capitalized
+    by mistake, this helper fixes it for envvars only.
+
+    Assume envvars are always str.
+    """
+    if value and value.strip() in ("True", "False"):
+        return value.lower()
+    return value

netlify.toml

@@ -1,6 +1,6 @@
 [build]
 # if commit is not tagged don't build
-# ignore = "git describe --exact-match && exit 1 || exit 0"
+ignore = "git describe --exact-match --tags HEAD && exit 1 || exit 0"
 publish = "site"
 command = "pip install -r requirements.txt && mkdocs build --clean"
 

tests/test_env_loader.py

@@ -505,3 +505,19 @@ def test_filtering_unknown_variables_with_prefix():
     assert not settings.get("IGNOREME")
     # Smoke test.
     assert settings.get("MYCONFIG") == "ham"
+
+
+def test_boolean_fix():
+    environ["BOOLFIX_CAPITALTRUE"] = "True"
+    environ["BOOLFIX_CAPITALFALSE"] = "False"
+    settings.IGNORE_UNKNOWN_ENVVARS_FOR_DYNACONF = False
+    load_from_env(
+        obj=settings,
+        prefix="BOOLFIX",
+        key=None,
+        silent=True,
+        identifier="env_global",
+        env=False,
+    )
+    assert settings.CAPITALTRUE is True
+    assert settings.CAPITALFALSE is False

tests/test_utils.py

@@ -24,6 +24,7 @@
 from dynaconf.utils import upperfy
 from dynaconf.utils.files import find_file
 from dynaconf.utils.files import get_local_filename
+from dynaconf.utils.parse_conf import boolean_fix
 from dynaconf.utils.parse_conf import evaluate_lazy_format
 from dynaconf.utils.parse_conf import Formatters
 from dynaconf.utils.parse_conf import Lazy
@@ -508,3 +509,13 @@ def test_add_converter_path_example(tmp_path):
     )
     settings = Dynaconf(settings_file=fn)
     assert isinstance(settings.my_path, Path)
+
+
+def test_boolean_fix():
+    """Assert boolean fix works"""
+    assert boolean_fix("True") == "true"
+    assert boolean_fix("False") == "false"
+    assert boolean_fix("NotOnlyTrue") == "NotOnlyTrue"
+    assert boolean_fix("TrueNotOnly") == "TrueNotOnly"
+    assert boolean_fix("FalseNotOnly") == "FalseNotOnly"
+    assert boolean_fix("NotOnlyFalse") == "NotOnlyFalse"

tests_functional/issues/976_True_False/.env

@@ -0,0 +1,4 @@
+DYNACONF_UPPERTRUE=True
+DYNACONF_UPPERFALSE=False
+DYNACONF_LOWERTRUE=true
+DYNACONF_LOWERFALSE=false

tests_functional/issues/976_True_False/app.py

@@ -0,0 +1,23 @@
+from __future__ import annotations
+
+from dynaconf import Dynaconf
+
+settings = Dynaconf(
+    settings_file="settings.toml",
+    load_dotenv=True,
+)
+
+
+# TOML must rely on its own type system
+assert settings.TOMLUPPERTRUE == "True"
+assert settings.TOMLUPPERFALSE == "False"
+assert settings.TOMLLOWERTRUE is True
+assert settings.TOMLLOWERFALSE is False
+
+# ENV vars must transform `True` to `true` and `False` to `false`
+assert settings.UPPERTRUE is True, settings.UPPERTRUE
+assert settings.UPPERFALSE is False, settings.UPPERFALSE
+assert settings.LOWERTRUE is True, settings.LOWERTRUE
+assert settings.LOWERFALSE is False, settings.LOWERFALSE
+
+print("BOOLEAN FIX FOR ENV VARS WORKS")

tests_functional/issues/976_True_False/settings.toml

@@ -0,0 +1,4 @@
+tomllowertrue = true
+tomllowerfalse = false
+tomluppertrue = "True"
+tomlupperfalse = "False"