Add final lesson tasks

students/bec_lukasz/lesson_14_decorators/Readme.md

@@ -0,0 +1,30 @@
+### Lesson 14 - Decorators
+#### introduction
+
+- [A guide to Python's function decorators](https://www.thecodeship.com/patterns/guide-to-python-function-decorators/)
+- [Easy introduction into decorators](https://www.python-course.eu/python3_decorators.php)
+
+#### practice projects
+
+1. Write `@sort` decorator that when applied to a function that returns a list, sorts this list, so we can do this:
+```
+@sort
+def data_feeder():
+  return [4,2,1,3]
+
+data_feeder() == [1,2,3,4] # <- this is True
+```
+
+2. Write `@access_required` decorator that when applied to a function executes subjected function only if `has_access` function from `authorization.py` returns `True`. So we can do this:
+```
+@access_required
+def restricted_print(*args, **kwargs):
+  print(*args, **kwargs)
+
+restricted_print('1 - visible')
+restricted_print('2 - invisible')
+restricted_print('3 - invisible')
+restricted_print('4 - visible')
+```
+
+3. Write `@logged` decorator using `logger_wrapper` from lesson 6. Apply it to several functions to demonstrate that it works.

students/bec_lukasz/lesson_14_decorators/access_required.py

@@ -0,0 +1,24 @@
+from lesson_14.authorization import has_access
+
+
+def access_required(func):
+    def func_wrapper(args):
+        if has_access():
+            return func(args)
+    return func_wrapper
+
+
+@access_required
+def restricted_print(*args, **kwargs):
+    print(*args, **kwargs)
+
+
+def main():
+    restricted_print('1 - visible')
+    restricted_print('2 - invisible')
+    restricted_print('3 - invisible')
+    restricted_print('4 - visible')
+
+
+if __name__ == '__main__':
+    main()

students/bec_lukasz/lesson_14_decorators/authorization.py

@@ -0,0 +1,14 @@
+access_count = -1
+
+
+def has_access():
+    '''
+    let's pretend this function calls some authorization services
+    returns True if access is granted and False if not
+    access is granted every 3rd time
+    '''
+    global access_count
+    access_count += 1
+    if access_count >= 3:
+        access_count = 0
+    return access_count == 0

students/bec_lukasz/lesson_14_decorators/decorator_training.py

@@ -0,0 +1,13 @@
+def get_text(name):
+   return "lorem ipsum, " + name + " dolor sit amet"
+
+
+def p_decorate(func):
+   def func_wrapper(name):
+       return "<p>" + func(name) + "</p>"
+   return func_wrapper
+
+
+my_get_text = p_decorate(get_text)
+
+print(my_get_text("John"))

students/bec_lukasz/lesson_14_decorators/logged.py

@@ -0,0 +1,21 @@
+from lesson_06.logger_wrapper import logger_wrapper
+
+
+def logged(func):
+    def func_wrapper(*args, **kwargs):
+        return logger_wrapper(func, *args, **kwargs)
+    return func_wrapper
+
+
+@logged
+def first_function(*args, **kwargs):
+    return str(args), str(kwargs)
+
+
+@logged
+def second_function():
+    return None
+
+
+print(first_function(1, 2, osiem=8))
+print(second_function())

students/bec_lukasz/lesson_14_decorators/sort.py

@@ -0,0 +1,12 @@
+def sort(func):
+    def list_sort():
+        return sorted(func())
+    return list_sort
+
+
+@sort
+def data_feeder():
+    return [4, 2, 1, 3]
+
+
+print(data_feeder())