Deploy FastAPI application with SQLite on Flyio

from python:3.13-alpineworkdir /appcopy ./requirements.txt .run pip install --no-cache-dir --upgrade -r requirements.txtcopy . /appenv host=0.0.0.0 port=8080expose ${port}cmd uvicorn main:app --host ${host} --port ${port}

import asyncioimport randomimport stringfrom urllib.parse import urlparseimport aiosqlitefrom fastapi import fastapi, httpexception, requestfrom fastapi.responses import redirectresponsedb_path = "/data/app.db"app = fastapi()async def get_db() -> aiosqlite.connection:    if db := getattr(get_db, "_db", none):        if db.is_alive:            return db    db = await aiosqlite.connect(db_path, loop=asyncio.get_event_loop())    db.row_factory = aiosqlite.row    qs = """    create table if not exists links (        created_at integer default (strftime('%s', 'now')),        short_code text primary key,        full_url text not null,        clicks integer default 0    )    """    await db.execute(qs)    await db.commit()    setattr(get_db, "_db", db)    return dbdef random_code(length=8) -> str:    alphabet = string.ascii_letters + string.digits    return "".join(random.choice(alphabet) for x in range(length))def is_valid_url(url: str) -> bool:    try:        parts = urlparse(url)        return all([parts.scheme, parts.netloc])    except valueerror:        return false@app.post("/")async def shorten(url: str, req: request):    if not is_valid_url(url):        raise httpexception(status_code=400, detail="invalid url")    host = req.headers.get("host")    if host is none:        raise httpexception(status_code=500, detail="missing host header")    short_code = random_code()    db = await get_db()    qs = "insert into links (short_code, full_url) values (?, ?)"    await db.execute(qs, (short_code, url))    await db.commit()    return f"https://{host}/{short_code}"@app.get("/")async def list_links():    db = await get_db()    qs = "select short_code, full_url, clicks from links order by created_at desc"    async with db.execute(qs) as cursor:        return await cursor.fetchall()@app.get("/{short_code}")async def redirect(short_code: str):    db = await get_db()    qs = """    update links set clicks = clicks + 1 where short_code = ?    returning full_url    """    async with db.execute(qs, (short_code,)) as cursor:        if row := await cursor.fetchone():            return redirectresponse(row["full_url"])    raise httpexception(status_code=404)

aiosqlitefastapiuvicorn

fly launch --build-only

fly volumes create sqlite_data -s 1 -r ams

[mounts]source = "sqlite_data"destination = "/data"

fly scale count 1

fly deploy

❯ curl -x post 'https://fly-fastapi-sqlite.fly.dev/?url=https://example.com'https://fly-fastapi-sqlite.fly.dev/8ydmfack

❯ curl -s 'https://fly-fastapi-sqlite.fly.dev/' | jq[  {    "short_code": "8ydmfack",    "full_url": "https://example.com",    "clicks": 1  }]

fly ssh sftp get /data/app.db ./app-backup.db