Merge pull request #321 from realpython/python-getter-setter

Add code examples for the getter and setter article

Author: KateFinegan

python-getter-setter/README.md

@@ -0,0 +1,3 @@
+# Getters and Setters: Manage Attributes in Python
+
+This folder provides the code examples for the article [Getters and Setters: Manage Attributes in Python](https://realpython.com/python-getter-setter/).

python-getter-setter/employee.py

@@ -0,0 +1,4 @@
+class Employee:
+    def __init__(self, name, birth_date):
+        self.name = name
+        self.birth_date = birth_date

python-getter-setter/employee2.py

@@ -0,0 +1,23 @@
+from datetime import date
+
+
+class Employee:
+    def __init__(self, name, birth_date):
+        self.name = name
+        self.birth_date = birth_date
+
+    @property
+    def name(self):
+        return self._name
+
+    @name.setter
+    def name(self, value):
+        self._name = value.upper()
+
+    @property
+    def birth_date(self):
+        return self._birth_date
+
+    @birth_date.setter
+    def birth_date(self, value):
+        self._birth_date = date.fromisoformat(value)

python-getter-setter/employee3.py

@@ -0,0 +1,32 @@
+from datetime import date
+
+
+class Employee:
+    def __init__(self, name, birth_date, start_date):
+        self.name = name
+        self.birth_date = birth_date
+        self.start_date = start_date
+
+    @property
+    def name(self):
+        return self._name
+
+    @name.setter
+    def name(self, value):
+        self._name = value.upper()
+
+    @property
+    def birth_date(self):
+        return self._birth_date
+
+    @birth_date.setter
+    def birth_date(self, value):
+        self._birth_date = date.fromisoformat(value)
+
+    @property
+    def start_date(self):
+        return self._start_date
+
+    @start_date.setter
+    def start_date(self, value):
+        self._start_date = date.fromisoformat(value)

python-getter-setter/employee4.py

@@ -0,0 +1,30 @@
+from datetime import date
+
+
+class Date:
+    def __set_name__(self, owner, name):
+        self._name = name
+
+    def __get__(self, instance, owner):
+        return instance.__dict__[self._name]
+
+    def __set__(self, instance, value):
+        instance.__dict__[self._name] = date.fromisoformat(value)
+
+
+class Employee:
+    birth_date = Date()
+    start_date = Date()
+
+    def __init__(self, name, birth_date, start_date):
+        self.name = name
+        self.birth_date = birth_date
+        self.start_date = start_date
+
+    @property
+    def name(self):
+        return self._name
+
+    @name.setter
+    def name(self, value):
+        self._name = value.upper()

python-getter-setter/label.py

@@ -0,0 +1,16 @@
+class Label:
+    def __init__(self, text, font):
+        self._text = text
+        self._font = font
+
+    def get_text(self):
+        return self._text
+
+    def set_text(self, value):
+        self._text = value
+
+    def get_font(self):
+        return self._font
+
+    def set_font(self, value):
+        self._font = value

python-getter-setter/label2.py

@@ -0,0 +1,10 @@
+class Label:
+    def __init__(self, text, font):
+        self.set_text(text)
+        self.font = font
+
+    def get_text(self):
+        return self._text
+
+    def set_text(self, value):
+        self._text = value.upper()  # Attached behavior

python-getter-setter/person.py

@@ -0,0 +1,13 @@
+class Person:
+    def __init__(self, name, birth_date):
+        self.name = name
+        self._birth_date = birth_date
+
+    def get_birth_date(self):
+        return self._birth_date
+
+    def set_birth_date(self, value, force=False):
+        if force:
+            self._birth_date = value
+        else:
+            raise AttributeError("can't set birth_date")

python-getter-setter/person2.py

@@ -0,0 +1,17 @@
+class Person:
+    def __init__(self, name):
+        self._name = name
+
+    @property
+    def name(self):
+        return self._name
+
+    @name.setter
+    def name(self, value):
+        self._name = value
+
+
+class Employee(Person):
+    @property
+    def name(self):
+        return super().name.upper()

python-getter-setter/person3.py

@@ -0,0 +1,14 @@
+class Person:
+    def __init__(self, name):
+        self._name = name
+
+    def get_name(self):
+        return self._name
+
+    def set_name(self, value):
+        self._name = value
+
+
+class Employee(Person):
+    def get_name(self):
+        return super().get_name().upper()