def test_flush_on_write(self):
# a very large query requires a flush loop to be sent to the backend
curs = self.conn.cursor()
for mb in 1, 5, 10, 20, 50:
size = mb * 1024 * 1024
stub = PollableStub(self.conn)
curs.execute("select %s;", ('x' * size,))
self.wait(stub)
self.assertEqual(size, len(curs.fetchone()[0]))
if stub.polls.count(ext.POLL_WRITE) > 1:
return
# This is more a testing glitch than an error: it happens
# on high load on linux: probably because the kernel has more
# buffers ready. A warning may be useful during development,
# but an error is bad during regression testing.
import warnings
warnings.warn("sending a large query didn't trigger block on write.")
python类POLL_WRITE的实例源码
def test_flush_on_write(self):
# a very large query requires a flush loop to be sent to the backend
curs = self.conn.cursor()
for mb in 1, 5, 10, 20, 50:
size = mb * 1024 * 1024
stub = PollableStub(self.conn)
curs.execute("select %s;", ('x' * size,))
self.wait(stub)
self.assertEqual(size, len(curs.fetchone()[0]))
if stub.polls.count(ext.POLL_WRITE) > 1:
return
# This is more a testing glitch than an error: it happens
# on high load on linux: probably because the kernel has more
# buffers ready. A warning may be useful during development,
# but an error is bad during regression testing.
import warnings
warnings.warn("sending a large query didn't trigger block on write.")
def test_flush_on_write(self):
# a very large query requires a flush loop to be sent to the backend
conn = self.conn
stub = self.set_stub_wait_callback(conn)
curs = conn.cursor()
for mb in 1, 5, 10, 20, 50:
size = mb * 1024 * 1024
del stub.polls[:]
curs.execute("select %s;", ('x' * size,))
self.assertEqual(size, len(curs.fetchone()[0]))
if stub.polls.count(psycopg2.extensions.POLL_WRITE) > 1:
return
# This is more a testing glitch than an error: it happens
# on high load on linux: probably because the kernel has more
# buffers ready. A warning may be useful during development,
# but an error is bad during regression testing.
import warnings
warnings.warn("sending a large query didn't trigger block on write.")
def crappy_callback(self, conn):
"""green callback failing after `self.to_error` time it is called"""
import select
from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE
while 1:
if self.to_error is not None:
self.to_error -= 1
if self.to_error <= 0:
raise ZeroDivisionError("I accidentally the connection")
try:
state = conn.poll()
if state == POLL_OK:
break
elif state == POLL_READ:
select.select([conn.fileno()], [], [])
elif state == POLL_WRITE:
select.select([], [conn.fileno()], [])
else:
raise conn.OperationalError("bad state from poll: %s" % state)
except KeyboardInterrupt:
conn.cancel()
# the loop will be broken by a server error
continue
def test_flush_on_write(self):
# a very large query requires a flush loop to be sent to the backend
curs = self.conn.cursor()
for mb in 1, 5, 10, 20, 50:
size = mb * 1024 * 1024
stub = PollableStub(self.conn)
curs.execute("select %s;", ('x' * size,))
self.wait(stub)
self.assertEqual(size, len(curs.fetchone()[0]))
if stub.polls.count(ext.POLL_WRITE) > 1:
return
# This is more a testing glitch than an error: it happens
# on high load on linux: probably because the kernel has more
# buffers ready. A warning may be useful during development,
# but an error is bad during regression testing.
import warnings
warnings.warn("sending a large query didn't trigger block on write.")
def wait_select(conn):
"""Wait until a connection or cursor has data available.
The function is an example of a wait callback to be registered with
`~psycopg2.extensions.set_wait_callback()`. This function uses
:py:func:`~select.select()` to wait for data available.
"""
import select
from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE
while 1:
state = conn.poll()
if state == POLL_OK:
break
elif state == POLL_READ:
select.select([conn.fileno()], [], [])
elif state == POLL_WRITE:
select.select([], [conn.fileno()], [])
else:
raise conn.OperationalError("bad state from poll: %s" % state)
def wait_select(conn):
"""Wait until a connection or cursor has data available.
The function is an example of a wait callback to be registered with
`~psycopg2.extensions.set_wait_callback()`. This function uses
:py:func:`~select.select()` to wait for data available.
"""
import select
from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE
while 1:
state = conn.poll()
if state == POLL_OK:
break
elif state == POLL_READ:
select.select([conn.fileno()], [], [])
elif state == POLL_WRITE:
select.select([], [conn.fileno()], [])
else:
raise conn.OperationalError("bad state from poll: %s" % state)
def wait_select(conn):
"""Wait until a connection or cursor has data available.
The function is an example of a wait callback to be registered with
`~psycopg2.extensions.set_wait_callback()`. This function uses
:py:func:`~select.select()` to wait for data available.
"""
import select
from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE
while 1:
state = conn.poll()
if state == POLL_OK:
break
elif state == POLL_READ:
select.select([conn.fileno()], [], [])
elif state == POLL_WRITE:
select.select([], [conn.fileno()], [])
else:
raise conn.OperationalError("bad state from poll: %s" % state)
def wait_select(conn):
"""Wait until a connection or cursor has data available.
The function is an example of a wait callback to be registered with
`~psycopg2.extensions.set_wait_callback()`. This function uses
:py:func:`~select.select()` to wait for data available.
"""
import select
from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE
while 1:
state = conn.poll()
if state == POLL_OK:
break
elif state == POLL_READ:
select.select([conn.fileno()], [], [])
elif state == POLL_WRITE:
select.select([], [conn.fileno()], [])
else:
raise conn.OperationalError("bad state from poll: %s" % state)
def wait_select(conn):
"""Wait until a connection or cursor has data available.
The function is an example of a wait callback to be registered with
`~psycopg2.extensions.set_wait_callback()`. This function uses
:py:func:`~select.select()` to wait for data available.
"""
import select
from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE
while 1:
state = conn.poll()
if state == POLL_OK:
break
elif state == POLL_READ:
select.select([conn.fileno()], [], [])
elif state == POLL_WRITE:
select.select([], [conn.fileno()], [])
else:
raise conn.OperationalError("bad state from poll: %s" % state)
def wait_select(conn):
"""Wait until a connection or cursor has data available.
The function is an example of a wait callback to be registered with
`~psycopg2.extensions.set_wait_callback()`. This function uses
:py:func:`~select.select()` to wait for data available.
"""
import select
from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE
while 1:
state = conn.poll()
if state == POLL_OK:
break
elif state == POLL_READ:
select.select([conn.fileno()], [], [])
elif state == POLL_WRITE:
select.select([], [conn.fileno()], [])
else:
raise conn.OperationalError("bad state from poll: %s" % state)
def wait_select(conn):
"""Wait until a connection or cursor has data available.
The function is an example of a wait callback to be registered with
`~psycopg2.extensions.set_wait_callback()`. This function uses
:py:func:`~select.select()` to wait for data available.
"""
import select
from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE
while 1:
state = conn.poll()
if state == POLL_OK:
break
elif state == POLL_READ:
select.select([conn.fileno()], [], [])
elif state == POLL_WRITE:
select.select([], [conn.fileno()], [])
else:
raise conn.OperationalError("bad state from poll: %s" % state)
def wait_select(conn):
"""Wait until a connection or cursor has data available.
The function is an example of a wait callback to be registered with
`~psycopg2.extensions.set_wait_callback()`. This function uses
:py:func:`~select.select()` to wait for data available.
"""
import select
from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE
while 1:
state = conn.poll()
if state == POLL_OK:
break
elif state == POLL_READ:
select.select([conn.fileno()], [], [])
elif state == POLL_WRITE:
select.select([], [conn.fileno()], [])
else:
raise conn.OperationalError("bad state from poll: %s" % state)
def test_flush_on_write(self):
# a very large query requires a flush loop to be sent to the backend
curs = self.conn.cursor()
for mb in 1, 5, 10, 20, 50:
size = mb * 1024 * 1024
stub = PollableStub(self.conn)
curs.execute("select %s;", ('x' * size,))
self.wait(stub)
self.assertEqual(size, len(curs.fetchone()[0]))
if stub.polls.count(ext.POLL_WRITE) > 1:
return
# This is more a testing glitch than an error: it happens
# on high load on linux: probably because the kernel has more
# buffers ready. A warning may be useful during development,
# but an error is bad during regression testing.
import warnings
warnings.warn("sending a large query didn't trigger block on write.")
def wait_select(conn):
"""Wait until a connection or cursor has data available.
The function is an example of a wait callback to be registered with
`~psycopg2.extensions.set_wait_callback()`. This function uses
:py:func:`~select.select()` to wait for data available.
"""
import select
from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE
while 1:
state = conn.poll()
if state == POLL_OK:
break
elif state == POLL_READ:
select.select([conn.fileno()], [], [])
elif state == POLL_WRITE:
select.select([], [conn.fileno()], [])
else:
raise conn.OperationalError("bad state from poll: %s" % state)
def wait_select(conn):
"""Wait until a connection or cursor has data available.
The function is an example of a wait callback to be registered with
`~psycopg2.extensions.set_wait_callback()`. This function uses
:py:func:`~select.select()` to wait for data available.
"""
import select
from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE
while 1:
state = conn.poll()
if state == POLL_OK:
break
elif state == POLL_READ:
select.select([conn.fileno()], [], [])
elif state == POLL_WRITE:
select.select([], [conn.fileno()], [])
else:
raise conn.OperationalError("bad state from poll: %s" % state)
def test_flush_on_write(self):
# a very large query requires a flush loop to be sent to the backend
conn = self.conn
stub = self.set_stub_wait_callback(conn)
curs = conn.cursor()
for mb in 1, 5, 10, 20, 50:
size = mb * 1024 * 1024
del stub.polls[:]
curs.execute("select %s;", ('x' * size,))
self.assertEqual(size, len(curs.fetchone()[0]))
if stub.polls.count(psycopg2.extensions.POLL_WRITE) > 1:
return
# This is more a testing glitch than an error: it happens
# on high load on linux: probably because the kernel has more
# buffers ready. A warning may be useful during development,
# but an error is bad during regression testing.
import warnings
warnings.warn("sending a large query didn't trigger block on write.")
def crappy_callback(self, conn):
"""green callback failing after `self.to_error` time it is called"""
import select
from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE
while 1:
if self.to_error is not None:
self.to_error -= 1
if self.to_error <= 0:
raise ZeroDivisionError("I accidentally the connection")
try:
state = conn.poll()
if state == POLL_OK:
break
elif state == POLL_READ:
select.select([conn.fileno()], [], [])
elif state == POLL_WRITE:
select.select([], [conn.fileno()], [])
else:
raise conn.OperationalError("bad state from poll: %s" % state)
except KeyboardInterrupt:
conn.cancel()
# the loop will be broken by a server error
continue
def test_flush_on_write(self):
# a very large query requires a flush loop to be sent to the backend
curs = self.conn.cursor()
for mb in 1, 5, 10, 20, 50:
size = mb * 1024 * 1024
stub = PollableStub(self.conn)
curs.execute("select %s;", ('x' * size,))
self.wait(stub)
self.assertEqual(size, len(curs.fetchone()[0]))
if stub.polls.count(ext.POLL_WRITE) > 1:
return
# This is more a testing glitch than an error: it happens
# on high load on linux: probably because the kernel has more
# buffers ready. A warning may be useful during development,
# but an error is bad during regression testing.
import warnings
warnings.warn("sending a large query didn't trigger block on write.")
def wait_select(conn):
"""Wait until a connection or cursor has data available.
The function is an example of a wait callback to be registered with
`~psycopg2.extensions.set_wait_callback()`. This function uses
:py:func:`~select.select()` to wait for data available.
"""
import select
from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE
while 1:
try:
state = conn.poll()
if state == POLL_OK:
break
elif state == POLL_READ:
select.select([conn.fileno()], [], [])
elif state == POLL_WRITE:
select.select([], [conn.fileno()], [])
else:
raise conn.OperationalError("bad state from poll: %s" % state)
except KeyboardInterrupt:
conn.cancel()
# the loop will be broken by a server error
continue
def wait_select(conn):
"""Wait until a connection or cursor has data available.
The function is an example of a wait callback to be registered with
`~psycopg2.extensions.set_wait_callback()`. This function uses
:py:func:`~select.select()` to wait for data available.
"""
import select
from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE
while 1:
try:
state = conn.poll()
if state == POLL_OK:
break
elif state == POLL_READ:
select.select([conn.fileno()], [], [])
elif state == POLL_WRITE:
select.select([], [conn.fileno()], [])
else:
raise conn.OperationalError("bad state from poll: %s" % state)
except KeyboardInterrupt:
conn.cancel()
# the loop will be broken by a server error
continue
def wait_select(conn):
"""Wait until a connection or cursor has data available.
The function is an example of a wait callback to be registered with
`~psycopg2.extensions.set_wait_callback()`. This function uses
:py:func:`~select.select()` to wait for data available.
"""
import select
from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE
while 1:
try:
state = conn.poll()
if state == POLL_OK:
break
elif state == POLL_READ:
select.select([conn.fileno()], [], [])
elif state == POLL_WRITE:
select.select([], [conn.fileno()], [])
else:
raise conn.OperationalError("bad state from poll: %s" % state)
except KeyboardInterrupt:
conn.cancel()
# the loop will be broken by a server error
continue
def wait_select(conn):
"""Wait until a connection or cursor has data available.
The function is an example of a wait callback to be registered with
`~psycopg2.extensions.set_wait_callback()`. This function uses
:py:func:`~select.select()` to wait for data available.
"""
import select
from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE
while 1:
try:
state = conn.poll()
if state == POLL_OK:
break
elif state == POLL_READ:
select.select([conn.fileno()], [], [])
elif state == POLL_WRITE:
select.select([], [conn.fileno()], [])
else:
raise conn.OperationalError("bad state from poll: %s" % state)
except KeyboardInterrupt:
conn.cancel()
# the loop will be broken by a server error
continue
def wait_select(conn):
"""Wait until a connection or cursor has data available.
The function is an example of a wait callback to be registered with
`~psycopg2.extensions.set_wait_callback()`. This function uses
:py:func:`~select.select()` to wait for data available.
"""
import select
from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE
while 1:
try:
state = conn.poll()
if state == POLL_OK:
break
elif state == POLL_READ:
select.select([conn.fileno()], [], [])
elif state == POLL_WRITE:
select.select([], [conn.fileno()], [])
else:
raise conn.OperationalError("bad state from poll: %s" % state)
except KeyboardInterrupt:
conn.cancel()
# the loop will be broken by a server error
continue
def eventlet_wait_callback(conn, timeout=-1):
"""A wait callback useful to allow eventlet to work with Psycopg."""
while 1:
state = conn.poll()
if state == extensions.POLL_OK:
break
elif state == extensions.POLL_READ:
trampoline(conn.fileno(), read=True)
elif state == extensions.POLL_WRITE:
trampoline(conn.fileno(), write=True)
else:
raise psycopg2.OperationalError(
"Bad result from poll: %r" % state)
def eventlet_wait_callback(conn, timeout=-1):
"""A wait callback useful to allow eventlet to work with Psycopg."""
while 1:
state = conn.poll()
if state == extensions.POLL_OK:
break
elif state == extensions.POLL_READ:
trampoline(conn.fileno(), read=True)
elif state == extensions.POLL_WRITE:
trampoline(conn.fileno(), write=True)
else:
raise psycopg2.OperationalError(
"Bad result from poll: %r" % state)
def gevent_wait_callback(conn, timeout=None):
"""A wait callback useful to allow gevent to work with Psycopg."""
while 1:
state = conn.poll()
if state == extensions.POLL_OK:
break
elif state == extensions.POLL_READ:
wait_read(conn.fileno(), timeout=timeout)
elif state == extensions.POLL_WRITE:
wait_write(conn.fileno(), timeout=timeout)
else:
raise psycopg2.OperationalError(
"Bad result from poll: %r" % state)
def wait_select(conn):
"""Wait until a connection or cursor has data available.
The function is an example of a wait callback to be registered with
`~psycopg2.extensions.set_wait_callback()`. This function uses
:py:func:`~select.select()` to wait for data available.
"""
import select
from psycopg2.extensions import POLL_OK, POLL_READ, POLL_WRITE
while 1:
try:
state = conn.poll()
if state == POLL_OK:
break
elif state == POLL_READ:
select.select([conn.fileno()], [], [])
elif state == POLL_WRITE:
select.select([], [conn.fileno()], [])
else:
raise conn.OperationalError("bad state from poll: %s" % state)
except KeyboardInterrupt:
conn.cancel()
# the loop will be broken by a server error
continue
