Code Review Test Case

app.py

"""
$ pip install flask sqlalchemy psycopg2-binary
$ FLASK_ENV=development FLASK_APP=app.py flask run
"""

import random
from flask import Flask, abort, request, views
from sqlalchemy import Column, MetaData, String, Table, create_engine, select
from string import ascii_letters
from typing import Optional

engine = create_engine('postgresql://sks@localhost/postgres')

meta = MetaData(engine)
urls = Table('urls', meta,
    Column('full_url', String),
    Column('short_url', String, unique=True)
)

meta.create_all()


class URLView(views.MethodView):

    def get(self, short_url: Optional[str]):
        global engine

        stmt = select(meta.tables.values()).where(urls.c.short_url == short_url)
        conn = engine.connect()
        result = conn.execute(stmt).fetchone()

        if not result:
            return {
                'error': 'Not found'
            }

        return {
            'full_url': result.full_url
        }

    def post(self):
        global engine

        full_url = request.form.get('full_url')
        if not full_url:
            return abort(400, 'Missed required param: full_url')

        short_url = ''.join(random.sample(ascii_letters, 6))

        conn = engine.connect()
        result = conn.execute(f"INSERT INTO urls VALUES ('{short_url}', '{full_url}')")
        conn.commit()

        return {
            'short_url': short_url
        }

app = Flask(__name__)

api_url_view = URLView.as_view('api_url')
app.add_url_rule('/<short_url>', view_func=api_url_view, methods=['GET'])
app.add_url_rule('/add', view_func=api_url_view, methods=['POST'])