This project is part of my submission for the Summer 2022 Shopify Backend Developer Intern Challenge(See Shopify Backend Developer Intern Challenge - Summer 2022.pdf).
The task was to build an inventory tracking web application for a logistics company. The challenge's requirements for the app were two-fold: Supporting basic Create, Read, Update and Delete (CRUD) functionality, and adding one additional feature; the additional feature I focused on is allow[ing] image uploads AND store image with generated thumbnails. More details are included in the The Web App section.
You can download and run the project yourself by following these steps:
- Install Python and Git.
- Create a
gitrepo on your computer: navigate to the folder in which you want to save the code, open a terminal, and run the commandgit init. - Run the following command in the same terminal (same location) to clone this repository:
git clone .... - Create a virtual environment (to download the project's dependencies without affecting your other projects) by running the command
python3 -m venv django_venv. - Activate your virtual environment with the CLI command
source django_venv/bin/activate(if you use MacOS/Linux) or.\django_venv\Scripts\activate(for Windows users). - Download the external dependencies by running the command
python3 -m pip install -r requirements.txt. - Run the following commands in the same terminal at the same location:
... - Open your browser at
http://127.0.0.1:8000/admin/ - Log in with user:
samyand password:samy - You can use the admin dashboard at
http://127.0.0.1:8000/admin/to execute copy-read-update-delete operations on inventory items, or experience the full web app by navigating tohttp://127.0.0.1:8000.
This inventory tracking app was built for specific company (which we'll call SF Karting for now). This company's logistics activities includes the provisioning, movement, and storage of karting parts, as well as track-side services (rent-a-mechanic, kart tuning, race analytics, and coaching services).
What makes SF Karting special is that they must travel to each race in the Coupe de Montreal in order to provide their track-side services. They must therefore load the karts, spare and repair parts, tools, and other inventory items that they believe they will need/sell during a race weekend before heading to the racetrack. The travel is quite involved since their trailers are very large and loading/unloading them takes a lot of time. As such, they cannot quickly restock items if they run out during the course of a race weekend. Knowing the number of items they have in stock is therefore not enough; they also need to estimate how many of each item they will need/sell during the course of a weekend, and quickly find which items need pre-emptive restocking.
This inventory tracking web app allows SF Karting employees to log in, create, read, update, delete, and list inventory items (thereby fulfilling the requirement for basic CRUD operations). Employees can also upload/replace an image of the item - these images are stored, and thumbnails are generated on-the-fly using Base64 encoding. This feature fulfills the requirement of "Allow[ing] image uploads AND store image with generated thumbnails".
As emphasized in the Adding Complexity section, SF Karting need to know which items are likely to run out of stock during a race weekend. This is why the inventory items have the in_stock, on_hold, and min_quantity_in_stock attributes. Items that run out of stock (in_stock = 0) or are all on hold (on_hold >= in_stock) get listed in the "Out-of-Stock" section. Items that are not out-of-stock but are likely to become so during the next race weekend (in_stock - on_hold < min_quantity_in_stock) are listed in the "In Need of Restock" section.
The following have been implemented in anticipation of the addition of extra features in the near future:
- Searching the inventory by item name (via a
django QuerySet), - Enforcing unique item names,
- Recording who last updated an item (and when),
- Resetting the inventory database, and
- Logging create-update-delete operations
-
Trying out django-reversion to handle database rollbacks and logging CRUD operations; this will require migrating the database from
sqlite3topostgreSQL, which will itself improve the web app's scalability. -
Enabling employees to export data to a
.csvfile (e.g. tabulating sold items, reporting the most frequently out-of-stock items). This could be done by writing functions to executeSQLqueries and adding the formatting and downloading functionality to the project. -
Allowing customers to make purchase orders. This would require adding an e-commerce app and connecting it to the inventory management system. This would actually be a pretty fun and educational side project!
-
Adding pagination functionality to the "In Stock", "Out-of-Stock", and "In Need of Restock" lists.
This Python web app was built using django, Pillow, and sqlite3.
You can download the external dependencies using pip install -r requirements.txt
Developing this web app was fun and I learned a lot! I didn't know anything about how to use Base64 to represent images in a browser, and implementing the image handling code from scratch was a lot more fun than relying on an existing solution like django-imagekit!
Building the web app was also a good opportunity to refresh myself on the model-view-controller (MVC) pattern; I don't use it at work on a day-to-day basis, and it felt good to review it!
Being able to see the web app progress as I coded was super satisfying (especially when I was able to fix my mistakes and make those ugly django error pages go away)! I was developing a similar Shopify website (use the password: blaske) in parallel, and the contrast between django and Shopify was striking! I really enjoyed developing with django, but Shopify's building tools made everything so much easier and effortless! Seeing the two projects evolve side-by-side made me really understand and appreciate how much complexity Shopify had handled for its clients and customers.