tests/multiprocessing.py
changeset 25 20a72a9a2d09
parent 24 5664afa530e5
child 26 7f219da7ab71
--- a/tests/multiprocessing.py	Thu Dec 15 18:21:41 2011 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,78 +0,0 @@
-#!/usr/bin/env python3
-'''Multiprocessing test.
-
-PgManager is partially safe against process forking.
-
-You can create connection credentials (create_conn) in main process, then fork
-and continue working with pgmanager in children processes. You can call create_conn again
-in children, but new connection credentials will be accessible only from process
-where it was created -- no sharing between processes.
-
-get_conn and cursor will still work after fork. Connections from parent process will
-be forgotten, that cannot be used un child process. 
-
-Connections cannot be shared between processes, DO NOT:
- * get_conn, then fork, then put_conn
- * get_conn, then fork, then use the connection, then .close()
-
-Good usage:
- * create_conn, fork, get_conn, cursor, etc.
-
-Basically, you can transfer only information from create_conn(), nothing else.
-
-'''
-
-
-import multiprocessing
-
-from config import Config
-from pgtoolkit import pgmanager
-
-
-def sub1(id):
-    with pgm.cursor() as curs:
-        print('[%d] pgconn: %d' % (multiprocessing.current_process().pid, curs.connection.get_backend_pid()))
-        print('[%d] update' % multiprocessing.current_process().pid)
-        curs.execute('''UPDATE test SET name = 'multi-1' WHERE id=%s''', [id])
-        print('[%d] commit' % multiprocessing.current_process().pid)
-        curs.connection.commit()
-
-def sub2(id):
-    pgm = pgmanager.get_instance()
-    with pgm.cursor() as curs:
-        print('[%d] pgconn: %d' % (multiprocessing.current_process().pid, curs.connection.get_backend_pid()))
-        print('[%d] update' % multiprocessing.current_process().pid)
-        curs.execute('''UPDATE test SET name = 'multi-2' WHERE id=%s''', [id])
-        print('[%d] commit' % multiprocessing.current_process().pid)
-        curs.connection.commit()
-
-
-cfg = Config('tests.conf')
-pgm = pgmanager.get_instance()
-pgm.create_conn(**cfg)
-
-with pgm.cursor() as curs:
-    print('[%d] pgconn: %d' % (multiprocessing.current_process().pid, curs.connection.get_backend_pid()))    
-    print('[%d] insert' % multiprocessing.current_process().pid)
-    curs.execute('''INSERT INTO test (name) VALUES ('multi') RETURNING id''')
-    id = curs.fetchone()[0]
-    curs.connection.commit()
-    
-    print('[%d] update' % multiprocessing.current_process().pid)
-    curs.execute('''UPDATE test SET name = 'multi-main' WHERE id=%s''', [id])
-    # not committed
-
-p1 = multiprocessing.Process(target=sub1, args=[id])
-p1.start()
-p2 = multiprocessing.Process(target=sub2, args=[id])
-p2.start()
-
-with pgm.cursor() as curs:
-    print('[%d] commit' % multiprocessing.current_process().pid)
-    curs.connection.commit()
-
-print('join')
-p1.join()
-p2.join()
-
-print('done')