X-Git-Url: https://git.ayoreis.com/Adafruit_Blinka-hackapet.git/blobdiff_plain/701655ace19cad12a315d91df4762c9f0b678ef9..046217cbbf14ba5a595d9423f58a7961f0ab51cd:/src/adafruit_blinka/__init__.py

diff --git a/src/adafruit_blinka/__init__.py b/src/adafruit_blinka/__init__.py
index 47622df..38ccec4 100755
--- a/src/adafruit_blinka/__init__.py
+++ b/src/adafruit_blinka/__init__.py
@@ -1,3 +1,6 @@
+# SPDX-FileCopyrightText: 2021 Melissa LeBlanc-Williams for Adafruit Industries
+#
+# SPDX-License-Identifier: MIT
 """
 `adafruit_blinka` - Runtime utility objects for re-implementation of CircuitPython API
 ======================================================================================
@@ -5,10 +8,18 @@
 * Author(s): cefn
 """
 
-class Enum():
+import os
+
+try:
+    import tomllib
+except ImportError:
+    import toml as tomllib
+
+
+class Enum:
     """
-        Object supporting CircuitPython-style of static symbols
-        as seen with Direction.OUTPUT, Pull.UP
+    Object supporting CircuitPython-style of static symbols
+    as seen with Direction.OUTPUT, Pull.UP
     """
 
     def __repr__(self):
@@ -26,8 +37,8 @@ class Enum():
     @classmethod
     def iteritems(cls):
         """
-            Inspects attributes of the class for instances of the class
-            and returns as key,value pairs mirroring dict#iteritems
+        Inspects attributes of the class for instances of the class
+        and returns as key,value pairs mirroring dict#iteritems
         """
         for key in dir(cls):
             val = getattr(cls, key)
@@ -37,6 +48,7 @@ class Enum():
 
 class ContextManaged:
     """An object that automatically deinitializes hardware with a context manager."""
+
     def __enter__(self):
         return self
 
@@ -47,11 +59,13 @@ class ContextManaged:
     def deinit(self):
         """Free any hardware used by the object."""
         return
+
     # pylint: enable=no-self-use
 
 
 class Lockable(ContextManaged):
     """An object that must be locked to prevent collisions on a microcontroller resource."""
+
     _locked = False
 
     def try_lock(self):
@@ -65,11 +79,47 @@ class Lockable(ContextManaged):
         """Release the lock so others may use the resource."""
         if self._locked:
             self._locked = False
-        else:
-            raise ValueError("Not locked")
+
+
+def load_settings_toml():
+    """Load values from settings.toml into os.environ, so that os.getenv returns them."""
+    if not os.path.isfile("settings.toml"):
+        raise FileNotFoundError("settings.toml not cound in current directory.")
+
+    print("settings.toml found. Updating environment variables:")
+    with open("settings.toml", "rb") as toml_file:
+        try:
+            settings = tomllib.load(toml_file)
+        except tomllib.TOMLDecodeError as e:
+            raise tomllib.TOMLDecodeError("Error with settings.toml file.") from e
+
+    invalid_types = set()
+    for key, value in settings.items():
+        if not isinstance(value, (bool, int, float, str)):
+            invalid_types.add(type(value).__name__)
+    if invalid_types:
+        invalid_types_string = ", ".join(invalid_types)
+        raise ValueError(
+            f"The types: '{invalid_types_string}' are not supported in settings.toml."
+        )
+
+    for key, value in settings.items():
+        key = str(key)
+        if key in os.environ:
+            print(f" - {key} already exists in environment")
+            continue
+        os.environ[key] = str(value)
+        print(f" - {key} added")
+
+    return settings
+
 
 def patch_system():
     """Patch modules that may be different due to the platform."""
+    # pylint: disable=import-outside-toplevel
     import sys
     from adafruit_blinka.agnostic import time
-    sys.modules['time'] = time
+
+    # pylint: enable=import-outside-toplevel
+
+    sys.modules["time"] = time