OIM3640 - Problem Solving and Software Design

2026 Spring

Session 22 (4/14)

Today's Agenda

• Announcements/Updates
• What We've Learned So Far
• Review Questions
• Flask Forms and POST Requests (lecture slides)
• MP3 Work Session
• Final Project Introduction

Announcements/Updates

• Mini Project 3 - Web App (MBTA + Mapbox)
  • Due: 4/21
  • Today: learn forms, then hands-on MP3 time
• Final Project - proposal due 4/17 (Fri)!
• Elective Projects - bonus opportunities (not required)
• Communication
  • Office Hours: Walk-in or by appointment
  • Email: Specify course # in subject, e.g., "OIM3640: GitHub settings"
  • You are required to meet with me at least once this semester
• Questions?

What We've Learned So Far

• Python Fundamentals: variables, types, functions, conditionals
• Iteration: for, while, break, continue
• Strings: indexing, slicing, methods
• Data Structures: lists, dicts, tuples, sets
• Error Handling: try/except/finally
• APIs: requests, JSON, GET/POST, API keys
• File I/O: read/write files, CSV, JSON
• Flask basics: routes, templates, URL parameters

Review Questions

from flask import Flask
app = Flask(__name__)

@app.get('/')
def home():
    return 'Hello!'

@app.get('/greet/<name>')
def greet(name):
    return f'Hi, {name}!'

• What URL would you visit to see "Hello!"?
• What URL would you visit to see "Hi, Alice!"?
• What does <name> do in the route?

Review Questions (continued)

@app.get('/hello/<name>')
def greet(name):
    return render_template('hello.html', name=name)

<!-- templates/hello.html -->
<h1>Hello, {{ name }}!</h1>

• What does render_template do?
• What does {{ name }} become when you visit /hello/Zhi?
• Where must the hello.html file be located?

Flask Forms and POST Requests

Let's continue with the Flask lecture slides - starting from "GET vs POST".

After the lecture, you'll have time to work on MP3.

Your Turn: MP3 Work Session

Work on your Mini Project 3:

1. If you haven't started: get Flask running, create app.py with a home page
2. If you have Flask running: add a form and handle the submission
3. If forms are working: connect to the Mapbox/MBTA APIs
4. If APIs are connected: display results in a template

Ask me or a classmate if you get stuck!

Final Project: Overview

Your capstone project - 25% of your grade.

• You choose the problem, the approach, and the scope
• Individual project
• Build something meaningful for your portfolio
• AI tools are encouraged (and documented)

Final Project: What to Build?

• Web app (Flask) - build on MP3
• Data analysis/visualization - build on MP2
• Automation - APIs and scripts
• AI-powered tool - OpenAI, Claude APIs
• Interdisciplinary - apply Python to another course or interest

A project built for someone (a club, a friend, a small business) often turns out better than one built in the abstract.

Final Project: Proposal (due 4/17)

Create proposal.md in a new public GitHub repo:

1. What are you building? (one or two sentences)
2. Why? (what motivates you, what problem does it solve)
3. MVP vs. Stretch Goals (minimum working version vs. nice-to-haves)
4. What don't you know yet? (be honest about unknowns)

Keep it short and focused. You've done this three times already.

Final Project: Requirements

Your repo must include:

• Working code that runs without errors
• README.md - what it does, how to install and run, API keys needed
• proposal.md - your proposal from 4/17
• AI_USAGE.md - document what you asked AI, what it generated, what you did with it, and what you learned
• Consistent commit history - not one big commit at the end
• No secrets in repo - use .env + .gitignore

Full instructions: project.md

Before You Leave

• Any questions?
• Start your Learning Log for this week (logs/wk12.md)
• Keep working on MP3 - due 4/21
• Start thinking about your Final Project - proposal due 4/17!
• Push your work to GitHub

Next session: Deploying your Flask app + MP3 code walk!