🧠 PHASE 1: Foundation (5--7 days max)

✅ Step 1: Web API Theory (You're doing now)

Topics:

• What is an API

• What is a REST API

• HTTP methods + status codes

• Client-server model

• Request-response cycle

Output:
Write your own summary in a web_api_notes.md file in your repo. Don't move forward until you can explain the basics without stuttering.

✅ Step 2: requests Module (2--3 days)

Topics:

• requests.get, .post, .put, .delete

• Sending headers, query params, JSON body

• Reading response.status_code, .json(), .text

Output:
Create a Python script that:

• Fetches data from a public API (e.g., https://jsonplaceholder.typicode.com/posts)

• Posts some dummy data

• Updates it

• Deletes it

Push this to GitHub under /requests-practice

✅ Step 3: os + json Modules (2--3 days)

Topics:

• os.path, os.getcwd(), os.environ, os.remove

• Reading and writing JSON files with json.load, json.dump

Output:

• Script that loads data from a .json file, modifies it, and saves it

• Use .env file + os.environ.get() to simulate secret handling

Push under /os-json-practice

🔧 PHASE 2: Flask & Backend (2--3 weeks)

✅ Step 4: Flask Basics

Topics:

• Flask, request, jsonify

• Routes (@app.route), HTTP methods

• Returning JSON, handling errors

Output:

• A Flask app with 3--4 routes (GET, POST, PUT, DELETE)

• Use in-memory dict or list as fake DB

Push to /flask-api-basics

✅ Step 5: MongoDB Integration

Topics:

• pymongo, MongoClient

• CRUD operations with MongoDB

• Connecting Flask to Mongo

Output:

• Convert the above Flask app to use MongoDB

• Store real data from client

Push to /flask-mongo-api

✅ Step 6: Authentication (JWT or token-based)

Topics:

• Flask-JWT-Extended or token system

• Login/signup routes

• Token generation, protected routes

Output:

• Add user system to your API

• Implement @jwt_required on protected routes

Push to /flask-auth-api

🧪 PHASE 3: Real Project + Deployment (2 weeks)

✅ Step 7: Build a Complete REST API Project

Example Ideas:

• Todo app with users and auth

• Notes app

• Expense tracker

Requirements:

• Flask + Mongo

• JWT Auth

• Full CRUD

• .env used properly

• Code modularized (Blueprints, services, routes)

Push to /your-final-api-project

✅ Step 8: Deployment

Platforms:

• Railway / Render / Fly.io

Output:

• API must be live on a public URL

• README with:

  • Base URL

  • Endpoints

  • Example usage

Completed topic notes

Core API Concepts -- Full Summary

(Your Theory Notes for Day 1)

1️⃣ What is an API?

🔹 API (Application Programming Interface) is a set of rules that allows two software systems to talk to each other.
🌐 In web dev, APIs let a client (browser/app) communicate with a server using HTTP and data formats like JSON.

📦 Think of it as a menu --- you don't know how the kitchen works, but you can order food through the menu. That's your API.

2️⃣ What is a REST API?

🔹 REST (Representational State Transfer) is a style of API design that follows these rules:

✅ Uses HTTP methods (GET, POST, PUT, DELETE)
✅ Works with resources (like /users/1, /notes)
✅ Communicates using JSON
🚫 Is stateless --- the server does not remember previous requests
📂 Allows clean, predictable access to data via URLs

3️⃣ HTTP Methods & Status Codes

🔧 Common HTTP Methods:

Method	Use Case	Description
GET	📥 Read	Retrieve data
POST	📝 Create	Add new data
PUT	🛠️ Update (Replace)	Update full resource
DELETE	🗑️ Delete	Remove a resource

📟 Common HTTP Status Codes:

Code	Meaning	When It Happens
200	✅ OK	Request succeeded
201	🆕 Created	POST request succeeded
400	❌ Bad Request	Client sent invalid or incomplete data
401	🔒 Unauthorized	Token missing/invalid
403	🚫 Forbidden	Valid token, but no access rights
404	❓ Not Found	Resource doesn't exist or wrong URL
500	💥 Server Error	Crash/bug on server

4️⃣ Client-Server Model

The client-server model separates the system into two roles:

🖥️ Client = sends HTTP requests (browser, app, frontend)
🧠 Server = receives request, processes it, and responds with data (usually from a DB)

🔗 They are independent systems connected only via HTTP communication.
This separation makes systems modular, reusable, and secure.

5️⃣ Request-Response Cycle

The request-response cycle is how a client and server interact every time a request is made.

🔁 Full Flow:

1. 📨 Client sends request (with method, headers, URL, body)

2. 🧠 Server receives and routes it to the correct function

3. 📂 Server runs logic, talks to the DB if needed

4. 📤 Server sends back a response (status + data)

5. 📲 Client receives the response, uses it to update UI or logic

🔚 Example (Python requests):

🎯 This sends a GET request, receives a 200 response, and prints the returned data.