ENSF 592 Spring 2023 - Assignment 5

📚 Learning Outcomes

• Create a simple Flask application with multiple routes
• Scrape and parse data from a single web page
• Store and manipulate data within a DataFrame
• Print a DataFrame object to a webpage

💻 Program Specifications

Follow along with the Lab 11 demonstration. The demo program is a collaborative effort between Garth Johnson and Emily Marasco, and is used with permission. Before submitting your files, you must complete the following tasks:

• Change "STUDENT NAME" to your own name in the code.
• Follow the "/hello/" route by entering your own name. Take a screenshot of the display.
• Modify the book table to display a new column with the sale price (reduced by 25%). Submit a screenshot of the modified table being displayed.
• Create a new route "/learn" that displays one thing that you learned in ENSF 592. Submit a screenshot of your answer being displayed.
• Your submitted code must match your provided screenshots.
• Your code will be run by the instructor/TAs as your end user.
• FAQs about the assignment will be answered in Lab 11 and on the D2L discussion boards. Please check the boards for any clarifications before submitting.
• The grading rubric will be posted to D2L.

To run your web application: MAC/Linux

• Make sure you are working in the correct directory
• export FLASK_ENV=development
• export FLASK_APP=web_data_app.py
• flask run

Windows

• Make sure you are working in the correct directory
• set FLASK_ENV=development
• set FLASK_APP=web_data_app.py
• flask run

The FLASK_ENV variable will be deprecated in future versions of Flask, but for now it allows us to enter development mode.

Once the application is running, browse the local system on port 5000 (typically http://localhost:5000/). When you do, you should see the friendly message "Hello World!" in your browser and the following in the terminal where the application is running: ❯ flask run * Serving Flask app "web_data_app.py" * Debug mode: on * WARNING: This is a development server. Do not use it in a production deployment. Use a production WSGI server instead. * Running on http://127.0.0.1:5000/ (Press CTRL+C to quit) * Restarting with watchdog (windowsapi) * Debugger is active! * Debugger PIN: 393-094-215 127.0.0.1 - - [7/Jun/2023 23:07:39] "GET / HTTP/1.1" 200 -

If you followed the ENSF 592 installation guidelines, you should have all the necessary modules ready to go. If you encounter issues, run the requirements file using pip install -r requirements.txt to ensure you have the correct versions necessary. Make sure you are in your assignment working directory and your ENSF 592 virtual environment.

📝 Assignment Tasks

• If you weren't able to attend the June 8th lab, be sure to watch the recording and follow along.
• Clone this repository to your local computer.
• Open VSCode and start a new terminal. Make sure that your ensf592 environment is activated.
• web_data_app.py is provided as a starting point. Add your name to the header.
• Remember to test your program execution via the terminal: run flask
• Fulfill the tasks above and upload the successful execution screenshots to your assignment repository.
• Commit your screenshots and code.
• Push your local git history to github.
• Submit your repository HTTPS link to the Assignment 5 D2L dropbox.
• Tip: If you want to learn more about a specific aspect of Python or Flask, remember to take a look at the official documentation!

📚 Developer Comments

First off, much of this is inspired by RealPython and various other sites, pages, and people encountered through the teaching and learning process. This is a basic 'quick n simple' Python-Flask application tutorial written for general usage of Python/Flask. This will help a new (but probably not noob) Pythonista learn how to set up a basic web server application in Python with Flask running on a local server, and assumes that the the developer is using Visual Studio Code as their IDE of choice. Flask is a Model-View-Controller (MVC) framework (see this page for some insight to what MVC is and isn't, and also Real Python's MVC Explained page for more details. If you'd like to try scraping more websites, take a look at http://toscrape.com/ If you'd like to expand on the book catalog example (without Flask), take a look at this link: https://towardsdatascience.com/a-really-gentle-introduction-to-web-scraping-in-python-83cb9e536db8