Implementation of interface (template) for all modules

- Correct setup of logging
- all inkycal-modules inherit from the given template
- Added basic, optional validation
- more code cleanups
- fixed a few minor bugs

inkycal/modules/template.py

@@ -0,0 +1,54 @@
+import abc
+from inkycal.custom import *
+
+class inkycal_module(metaclass=abc.ABCMeta):
+  """Generic base class for inykcal modules"""
+
+  @classmethod
+  def __subclasshook__(cls, subclass):
+    return (hasattr(subclass, 'generate_image') and
+      callable(subclass.generate_image) or
+      NotImplemented)
+
+  def __init__(self, section_size, section_config):
+    # Initializes base module
+    # sets properties shared amongst all sections
+    self.config = section_config
+    self.width, self.height = section_size
+    self.fontsize = 12
+    self.margin_x = 0.02
+    self.margin_y = 0.05
+    self.font = ImageFont.truetype(
+      fonts['NotoSans-SemiCondensed'], size = self.fontsize)
+
+  def set(self, help=False, **kwargs):
+    """Set attributes of class, e.g. class.set(key=value)
+    see that can be changed by setting help to True
+    """
+    lst = dir(self).copy()
+    options = [_ for _ in lst if not _.startswith('_')]
+    if 'logger' in options: options.remove('logger')
+
+    if help == True:
+      print('The following can be configured:')
+      print(options)
+
+    for key, value in kwargs.items():
+      if key in options:
+        setattr(self, key, value)
+        print("set '{}' to '{}'".format(key,value))
+      else:
+        print('{0} does not exist'.format(key))
+        pass
+
+    # Check if validation has been implemented
+    try:
+      self._validate()
+    except AttributeError:
+      print('no validation implemented')
+
+  @abc.abstractmethod
+  def generate_image(self):
+    # Generate image for this module with specified parameters
+    raise NotImplementedError(
+      'The developers were too lazy to implement this function')