python-cx_Oracle/samples/tutorial/aq.py

75 lines
2.4 KiB
Python

#------------------------------------------------------------------------------
# aq.py (Section 10.1)
#------------------------------------------------------------------------------
#------------------------------------------------------------------------------
# Copyright (c) 2017, 2018, Oracle and/or its affiliates. All rights reserved.
#------------------------------------------------------------------------------
from __future__ import print_function
import cx_Oracle
import decimal
import db_config
con = cx_Oracle.connect(db_config.user, db_config.pw, db_config.dsn)
cur = con.cursor()
BOOK_TYPE_NAME = "UDT_BOOK"
QUEUE_NAME = "BOOKS"
QUEUE_TABLE_NAME = "BOOK_QUEUE_TABLE"
# Cleanup
cur.execute(
"""begin
dbms_aqadm.stop_queue('""" + QUEUE_NAME + """');
dbms_aqadm.drop_queue('""" + QUEUE_NAME + """');
dbms_aqadm.drop_queue_table('""" + QUEUE_TABLE_NAME + """');
execute immediate 'drop type """ + BOOK_TYPE_NAME + """';
exception when others then
if sqlcode <> -24010 then
raise;
end if;
end;""")
# Create type
print("Creating books type UDT_BOOK...")
cur.execute("""
create type %s as object (
title varchar2(100),
authors varchar2(100),
price number(5,2)
);""" % BOOK_TYPE_NAME)
# Create queue table and queue and start the queue
print("Creating queue table...")
cur.callproc("dbms_aqadm.create_queue_table",
(QUEUE_TABLE_NAME, BOOK_TYPE_NAME))
cur.callproc("dbms_aqadm.create_queue", (QUEUE_NAME, QUEUE_TABLE_NAME))
cur.callproc("dbms_aqadm.start_queue", (QUEUE_NAME,))
# Enqueue a few messages
booksType = con.gettype(BOOK_TYPE_NAME)
book1 = booksType.newobject()
book1.TITLE = "The Fellowship of the Ring"
book1.AUTHORS = "Tolkien, J.R.R."
book1.PRICE = decimal.Decimal("10.99")
book2 = booksType.newobject()
book2.TITLE = "Harry Potter and the Philosopher's Stone"
book2.AUTHORS = "Rowling, J.K."
book2.PRICE = decimal.Decimal("7.99")
options = con.enqoptions()
messageProperties = con.msgproperties()
for book in (book1, book2):
print("Enqueuing book", book.TITLE)
con.enq(QUEUE_NAME, options, messageProperties, book)
con.commit()
# Dequeue the messages
options = con.deqoptions()
options.navigation = cx_Oracle.DEQ_FIRST_MSG
options.wait = cx_Oracle.DEQ_NO_WAIT
while con.deq(QUEUE_NAME, options, messageProperties, book):
print("Dequeued book", book.TITLE)
con.commit()