Housing Inventory Tracker - A PyBites code challenge
I have recently stumbled across the twitter tag #100daysOfCode, the idea being to code or do some supplementary learning towards coding for 100 days in a row. I am 7 days in and am already finding myself thinking about code and problems I could solve much more regularly throughout my daily life.
Todays challenge was taken from PyBites Code Challenges, a blog hosting free, open ended tasks released periodically to complete in your own time and then share with the community. This is task 8, a good year behind the most current challenge but I hope to catch up during my 100 days of code.
The challenge
The challenge is simple with some added options if you wish to take it a few steps further. The instructions from PyBites:
House Inventory Tracker Requirements
-
Create a list of rooms (doesn’t have to use the list type).
-
Each room in your rooms list needs to contain at least 5 items (ie, TV, couch, table, etc) and the relative dollar value of each item.
-
The script you will write will print out each room along with the individual items and values. This needs to be properly formatted, eg: no printing a dict as is.
There were also some bonus parts to the challenge:
These are bonus features. Not required but cool to try if you’re interested:
-
Create some sort of program shell with a menu system around this. ie, “Which room would you like to list out?”
-
If you’re really game, allow users to create rooms and update information.
-
You could even make an API with Flask or your preferred framework
-
Print the total dollar value of each room and the entire house.
-
Have persistent storage of the data. sqlite3 = stdlib and light-weight, but feel free to use your preferred DB / module.
There are clearly many ways in which to approach this challenge, simply entering the information in a script in the form of lists or a dataframe would allow the results to be printed to the screen. However having had little practice creating classes I opted to model the house as a class instance, allowing for the whole process to be easily user controlled after the script has been run, first creating the house, then adding rooms and items.
import json
class House:
"""
A class for storing household inventory.
Attributes
name (str) : Name of the house.
total_value (int) : Total value of items in the house.
rooms (dict) : A dictionary of rooms, each rooms value being a dictionary of items
within that room along with its dollar value.
"""
def __init__(self, name, rooms = None):
"""
The constructor for House class.
Parameters:
name (str) : Name of the house.
rooms (dict) : Defaults to None, an optional input allowed a previously created
House class to be loaded.
"""
self.name = name
self.total_value = 0
if rooms:
self.rooms = rooms
self.update_total()
else:
self.rooms = {}
def update_total(self):
"Updates total_value attribute"
self.total_value = sum(sum(self.rooms[room].values()) for room in self.rooms.keys())
def add_room(self, name):
"Add room name to rooms attribute"
self.rooms[name] = {}
def add_item(self, item_name, value, room):
"""
Add item to rooms attribute, creating room if room does not exist.
Parameters:
item_name (str, list) : Item or items to be added to house inventory
value (str, list) : Value of item or items to be added.
room (str) : Location of item or items to be added.
tota_value updates after items are added.
"""
if room not in house.rooms:
self.add_room(room)
if type(item_name) == list:
for item, value in zip(item_name, value):
self.rooms[room][item] = value
else:
self.rooms[room][item_name] = value
self.update_total()
def remove_item(self, item_name, room):
"""
Remove item from rooms attribute.
Parameters:
item_name (str) : Name of item to remove.
room (str) : Location of item to remove
total_value updates after items are removed.
"""
del self.rooms[room][item_name]
self.update_total()
def print_items(self):
"Print full inventory including room totals and grand total."
print('{:*^40}'.format(self.name))
for room in self.rooms.keys():
print(room)
for item, value in self.rooms[room].items():
print(' {:<15} : {}'.format(item, value))
print('Room total : {}'.format(sum(self.rooms[room].values())))
print('-'*10)
print('Grand Total : {}'.format(self.total_value))
def save_house_to_disk(self, path='house.json'):
"""
Save house class to disk as JSON file."
Parameters:
path (str) : Filepath for outfile.
"""
with open(path, 'w') as file:
json.dump(self.rooms, file)
As defined in the docstrings, the class has three attributes, a name, total value and “rooms” which holds the full inventory and each items location. The methods are all self explanatory, the update_total is used to update the total_value attribute when items are added or removed from the inventory.
We can now create a house and add some items.
house = House('My Place')
house.add_room('Garage')
house.rooms
{'Garage': {}}
house.add_item('Bike', 500, 'Garage')
house.rooms
{'Garage': {'Bike': 500}}
things = ['Saw', 'Roof Box', 'Sofa', 'Workbench']
values = [200, 250, 150, 25]
house.add_item(things, values, 'Garage')
house.rooms
{'Garage': {'Bike': 500,
'Roof Box': 250,
'Saw': 200,
'Sofa': 150,
'Workbench': 25}}
house.print_items()
****************My Place****************
Garage
Bike : 500
Saw : 200
Roof Box : 250
Sofa : 150
Workbench : 25
Room total : 1125
----------
Grand Total : 1125
house.remove_item('Saw', 'Garage')
house.print_items()
****************My Place****************
Garage
Bike : 500
Roof Box : 250
Sofa : 150
Workbench : 25
Room total : 925
----------
Grand Total : 925
dr_items = ['Dining Table', 'Sideboard', 'Lighting', 'Cutlery', 'Placemats', 'Curtains']
dr_values = [700, 300, 100, 25, 20, 90]
house.add_item(dr_items, dr_values, 'Dining Room')
lr_things = ['TV', 'TV Stand', 'Coffee Table', 'Sofa', 'Curtains']
lr_values = [1000, 300, 150, 200, 100]
house.add_item(lr_things, lr_values, 'Living Rooms')
house.add_item('Shelving', 25, 'Garage')
house.print_items()
****************My Place****************
Garage
Bike : 500
Roof Box : 250
Sofa : 150
Workbench : 25
Shelving : 25
Room total : 950
----------
Dining Room
Dining Table : 700
Sideboard : 300
Lighting : 100
Cutlery : 25
Placemats : 20
Curtains : 90
Room total : 1235
----------
Living Rooms
TV : 1000
TV Stand : 300
Coffee Table : 150
Sofa : 200
Curtains : 100
Room total : 1750
----------
Grand Total : 3935
Now we have finished entering our items, we can call the save_house_to_disk method, leaving the default filepath ‘house.json’ and save our house for later.
house.save_house_to_disk()
To load the house, we add a supplementary function. Provided we navigate to the same working directory we last worked on the house, we can use the default path again.
def load_house(name, path='house.json'):
with open(path) as file:
house_data = json.load(file)
house = House(name, house_data)
return house
loaded_house = load_house('House reloaded')
loaded_house.print_items()
*************House reloaded*************
Garage
Bike : 500
Roof Box : 250
Sofa : 150
Workbench : 25
Shelving : 25
Room total : 950
----------
Dining Room
Dining Table : 700
Sideboard : 300
Lighting : 100
Cutlery : 25
Placemats : 20
Curtains : 90
Room total : 1235
----------
Living Rooms
TV : 1000
TV Stand : 300
Coffee Table : 150
Sofa : 200
Curtains : 100
Room total : 1750
----------
Grand Total : 3935
Summary
A simple house inventory tracker using a python class. While not completing all of the bonus brief it allows full user input and for the inventory to be easily saved and reloaded at a later date.