fast-api

A small social-style backend: register and log in with JWTs, upload images and videos via ImageKit, and read a feed of posts. Stack: FastAPI, SQLAlchemy (async) + SQLite, fastapi-users, optional Streamlit demo (frontend.py).

Stack

Area	Choice
HTTP API	FastAPI
Auth	fastapi-users (JWT)
Database	SQLite (test.db), created on startup
Media	ImageKit uploads
Demo UI	Streamlit → http://localhost:8000

Open http://localhost:8000/docs for interactive OpenAPI when the server is running.

Requirements

• Python 3.13+ (pyproject.toml)
• uv (recommended)
• ImageKit account and keys

Setup

1. Clone the repo and enter the project directory.

2. Copy environment template and fill in values:

   cp .env.example .env

   Variable	Notes
   JWT_SECRET_KEY	Long random string; signs JWTs
   IMAGEKIT_PRIVATE_KEY	Server uploads
   IMAGEKIT_PUBLIC_KEY	Listed in .env.example for parity with ImageKit; wire in app if you need client-side upload
   IMAGEKIT_URL_ENDPOINT	e.g. https://ik.imagekit.io/your_id — used for URL transforms in Streamlit

3. Install dependencies:

   uv sync

Run the API

uv run python main.py

Runs uvicorn on 0.0.0.0:8000 with reload (app.app:app).

Equivalent:

uv run uvicorn app.app:app --reload --host 0.0.0.0 --port 8000

Run the Streamlit app (optional)

Terminal 1: API as above. Terminal 2:

uv run streamlit run frontend.py

Use the URL Streamlit prints (usually http://localhost:8501).

Note: frontend.py calls /upload, /feed, and /posts/{id}. The router mounts posts under /posts, so working paths are POST /posts/upload, GET /posts/feed, and DELETE /posts/posts/{post_id}. If the UI returns 404 on feed or upload, update those URLs in frontend.py to match /docs.

Main HTTP surfaces

• Auth / users — fastapi-users routes (register, JWT login, /users/me, etc.) — see /docs
• Posts (Bearer token required):
  • POST /posts/upload — multipart file + optional caption
  • GET /posts/feed — feed JSON
  • DELETE /posts/posts/{post_id} — delete (path reflects current router prefix + handler path)

Repo layout

fast-api/
├── main.py              # Dev server entry
├── frontend.py          # Streamlit client
├── .env.example         # Env template
├── pyproject.toml
├── uv.lock
├── app/
│   ├── app.py           # FastAPI app + routers
│   ├── db.py            # Engine, models, session
│   ├── users.py         # JWT + UserManager
│   ├── images.py        # ImageKit client
│   ├── schemas.py
│   └── modules/posts/   # Routes + controllers
└── test.db              # Created when the API runs

Troubleshooting

• JWT errors — Set JWT_SECRET_KEY in .env and restart the API.
• Upload failures — Check IMAGEKIT_PRIVATE_KEY and ImageKit dashboard.
• Port 8000 busy — Change port in main.py or pass --port to uvicorn; update frontend.py URLs if you use Streamlit.