object_aq_async.py

# -----------------------------------------------------------------------------
# Copyright (c) 2025, Oracle and/or its affiliates.
#
# Portions Copyright 2007-2015, Anthony Tuininga. All rights reserved.
#
# Portions Copyright 2001-2007, Computronix (Canada) Ltd., Edmonton, Alberta,
# Canada. All rights reserved.
#
# This software is dual-licensed to you under the Universal Permissive License
# (UPL) 1.0 as shown at https://oss.oracle.com/licenses/upl and Apache License
# 2.0 as shown at http://www.apache.org/licenses/LICENSE-2.0. You may choose
# either license.
#
# If you elect to accept the software under the Apache License, Version 2.0,
# the following applies:
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
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#
#    https://www.apache.org/licenses/LICENSE-2.0
#
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# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
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# -----------------------------------------------------------------------------

# -----------------------------------------------------------------------------
# object_aq.py
#
# Demonstrates how to use advanced queuing with objects. It makes use of a
# simple type and queue created in the sample setup.
# -----------------------------------------------------------------------------

import asyncio
import decimal

import oracledb
import sample_env

BOOK_TYPE_NAME = "UDT_BOOK"
QUEUE_NAME = "DEMO_BOOK_QUEUE"
BOOK_DATA = [
    (
        "The Fellowship of the Ring",
        "Tolkien, J.R.R.",
        decimal.Decimal("10.99"),
    ),
    (
        "Harry Potter and the Philosopher's Stone",
        "Rowling, J.K.",
        decimal.Decimal("7.99"),
    ),
]


async def main():

    # connect to database
    connection = await oracledb.connect_async(
        user=sample_env.get_main_user(),
        password=sample_env.get_main_password(),
        dsn=sample_env.get_connect_string(),
    )

    # create a queue
    books_type = await connection.gettype(BOOK_TYPE_NAME)
    queue = connection.queue(QUEUE_NAME, payload_type=books_type)
    queue.deqoptions.wait = oracledb.DEQ_NO_WAIT
    queue.deqoptions.navigation = oracledb.DEQ_FIRST_MSG

    # dequeue all existing messages to ensure the queue is empty, just so that
    # the results are consistent
    while await queue.deqone():
        pass

    # enqueue a few messages
    print("Enqueuing messages...")
    for title, authors, price in BOOK_DATA:
        book = books_type.newobject()
        book.TITLE = title
        book.AUTHORS = authors
        book.PRICE = price
        print(title)
        await queue.enqone(connection.msgproperties(payload=book))
    await connection.commit()

    # dequeue the messages
    print("\nDequeuing messages...")
    while True:
        props = await queue.deqone()
        if not props:
            break
        print(props.payload.TITLE)
    await connection.commit()
    print("\nDone.")


asyncio.run(main())