from config_db import DB_USER, DB_NAME, DB_PASS, DB_HOST
from peewee import PostgresqlDatabase, OperationalError
from backoff import expo, on_exception

database = PostgresqlDatabase(
        DB_NAME,
        user=DB_USER,
        password=DB_PASS,
        host=DB_HOST,
        autorollback=True
    )

@on_exception(expo, OperationalError, max_tries=8)
def create_connection():
    try:
        database.connection()
    except OperationalError:
        database.connect(reuse_if_open=True)


@on_exception(expo, OperationalError, max_tries=8)
def destroy_connection(exc):
    if not database.is_closed():
        database.close()

def init(app):

    app.before_request(create_connection)
    app.teardown_request(destroy_connection)