Routing, database connection pooling, HTTP responses, sessions

app.py

import flask
import os
import psycopg2
import psycopg2.pool

app = flask.Flask(__name__)
app.secret_key = '@1*V*vpVqqfyhCZ)s/`5>B^V]mJ85]We'
app.debug = True

pool = psycopg2.pool.SimpleConnectionPool(
    1, ## Min
    1, ## Max
    host=os.getenv('DB_SERVER'),
    port='5432',
    database=os.getenv('DB_NAME'),
    user=os.getenv('DB_USER'),
    password=os.getenv('DB_PASSWORD'))

@app.route("/go/<oid>")
def go(oid):
  flask.session['lookups'] = flask.session.get('lookups', 0) + 1
  conn = pool.getconn()
  cur = conn.cursor()
  try:
    cur.execute('''
    select name
    from object
    where id = %s;
    ''', (oid,))
    oname = cur.fetchone()[0]
    cur.close()
    return oname + '\n' + str(flask.session['lookups']) + ' so far.' + '\n'
  except:
    flask.abort(404)
  finally:
    pool.putconn(conn)
    
@app.errorhandler(404)
def error404(error):
  return 'Yo. Not found.'

if __name__ == "__main__":
  app.run()