Revert "Revert "Add a timeout for the image build""

This reverts commit ccf40a462a.

The previous version would not work properly when daemonized
because there was no stdout. This version maintains stdout and
uses select/poll with non-blocking stdout to capture the output
to a log file.

Depends-On: https://review.openstack.org/634266

Change-Id: I7f0617b91e071294fe6051d14475ead1d7df56b7
This commit is contained in:
David Shrewsbury 2019-01-29 11:50:08 -05:00
parent acf038aef4
commit 890ea4975e
9 changed files with 142 additions and 22 deletions

View File

@ -277,6 +277,12 @@ Options
Specifies the distro to be used as a base image to build the image using
diskimage-builder.
.. attr:: build-timeout
:type: int
How long (in seconds) to wait for the diskimage build before giving up.
The default is 8 hours.
.. attr:: elements
:type: list

View File

@ -13,8 +13,10 @@
# License for the specific language governing permissions and limitations
# under the License.
import fcntl
import logging
import os
import select
import shutil
import socket
import subprocess
@ -42,6 +44,9 @@ SUSPEND_WAIT_TIME = 30
# so just hardcode it for all qcow2 building
DEFAULT_QEMU_IMAGE_COMPAT_OPTIONS = "--qemu-img-options 'compat=0.10'"
# DIB process polling timeout, in milliseconds
BUILD_PROCESS_POLL_TIMEOUT = 30 * 1000
class DibImageFile(object):
'''
@ -750,6 +755,7 @@ class BuildWorker(BaseWorker):
self.log.info('Logging to %s' % (log_fn,))
start_time = time.monotonic()
try:
p = subprocess.Popen(
shlex.split(cmd),
@ -761,17 +767,73 @@ class BuildWorker(BaseWorker):
"Failed to exec '%s'. Error: '%s'" % (cmd, e.strerror)
)
with open(log_fn, 'wb') as log:
while True:
ln = p.stdout.readline()
log.write(ln)
log.flush()
if not ln:
break
# Make subprocess stdout non-blocking
fd = p.stdout.fileno()
fl = fcntl.fcntl(fd, fcntl.F_GETFL)
fcntl.fcntl(fd, fcntl.F_SETFL, fl | os.O_NONBLOCK)
rc = p.wait()
m = "Exit code: %s\n" % rc
log.write(m.encode('utf8'))
# Poll subprocess stdout for readability
r, w, e = select.select([fd], [], [], 0)
bitmask = (select.POLLIN | select.POLLHUP)
poll = select.poll()
poll.register(fd, bitmask)
rc = None
did_timeout = False
subprocess_done = False
def buildDidTimeout():
build_time = time.monotonic() - start_time
if build_time > diskimage.build_timeout:
return True
return False
with open(log_fn, 'wb') as log:
# While the subprocess is running, we will loop through stdout
# events. If we can read data, write that out to the log file.
# If the subprocess completes, set the flag so we can exit and
# write the return code.
#
# We check for build timeouts in two places: after we have read
# all available data in the buffer (which will cause an early exit
# of the poll loop), and after a poll timeout. If we did not have
# a check after the reads, we would have to have a poll timeout
# to occur to check for a build timeout, which may not happen if
# there is constantly data available for reading.
while not subprocess_done:
for fd, event in poll.poll(BUILD_PROCESS_POLL_TIMEOUT):
# Data available for reading
if event & select.POLLIN:
data = p.stdout.read(1024)
while data:
log.write(data)
log.flush()
data = p.stdout.read(1024)
if buildDidTimeout():
break
# Subprocess complete
elif event & select.POLLHUP:
subprocess_done = True
rc = p.wait()
if not subprocess_done:
if buildDidTimeout():
did_timeout = True
rc = 1
self.log.error(
"Build timeout for image %s, build %s (log: %s)",
diskimage.name, build_id, log_fn)
p.kill()
break
# Subprocess finished, write return code
if not did_timeout:
m = "Exit code: %s\n" % rc
log.write(m.encode('utf8'))
# It's possible the connection to the ZK cluster could have been
# interrupted during the build. If so, wait for it to return.
@ -796,9 +858,10 @@ class BuildWorker(BaseWorker):
self.log.info("ZooKeeper lost while building %s" % diskimage.name)
self._zk.resetLostFlag()
build_data.state = zk.FAILED
elif p.returncode:
elif p.returncode or did_timeout:
self.log.info(
"DIB failed creating %s (%s)" % (diskimage.name, p.returncode))
"DIB failed creating %s (%s) (timeout=%s)" % (
diskimage.name, p.returncode, did_timeout))
build_data.state = zk.FAILED
else:
self.log.info("DIB image %s is built" % diskimage.name)

View File

@ -44,6 +44,7 @@ class ConfigValidator:
'rebuild-age': int,
'env-vars': {str: str},
'username': str,
'build-timeout': int,
}
webapp = {

View File

@ -118,6 +118,7 @@ class Config(ConfigValue):
d.image_types = set(diskimage.get('formats', []))
d.pause = bool(diskimage.get('pause', False))
d.username = diskimage.get('username', 'zuul')
d.build_timeout = diskimage.get('build-timeout', (8 * 60 * 60))
self.diskimages[d.name] = d
def setSecureDiskimageEnv(self, diskimages, secure_config_path):
@ -179,6 +180,7 @@ class DiskImage(ConfigValue):
self.image_types = None
self.pause = False
self.username = None
self.build_timeout = None
def __eq__(self, other):
if isinstance(other, DiskImage):
@ -189,7 +191,8 @@ class DiskImage(ConfigValue):
other.env_vars == self.env_vars and
other.image_types == self.image_types and
other.pause == self.pause and
other.username == self.username)
other.username == self.username and
other.build_timeout == self.build_timeout)
return False
def __repr__(self):

View File

@ -411,20 +411,25 @@ class DBTestCase(BaseTestCase):
time.sleep(1)
self.wait_for_threads()
def waitForBuild(self, image_name, build_id):
def waitForBuild(self, image_name, build_id, states=None):
if states is None:
states = (zk.READY,)
base = "-".join([image_name, build_id])
while True:
self.wait_for_threads()
files = builder.DibImageFile.from_image_id(
self._config_images_dir.path, base)
if files:
break
time.sleep(1)
while True:
self.wait_for_threads()
build = self.zk.getBuild(image_name, build_id)
if build and build.state == zk.READY:
if build and build.state in states:
break
time.sleep(1)
# We should only expect a dib manifest with a successful build.
while build.state == zk.READY:
self.wait_for_threads()
files = builder.DibImageFile.from_image_id(
self._config_images_dir.path, base)
if files:
break
time.sleep(1)

View File

@ -152,6 +152,7 @@ diskimages:
- cache-devstack
release: trusty
rebuild-age: 3600
build-timeout: 3600
env-vars:
TMPDIR: /opt/dib_tmp
DIB_IMAGE_CACHE: /opt/dib_cache

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@ -0,0 +1,27 @@
elements-dir: .
images-dir: '{images_dir}'
build-log-dir: '{build_log_dir}'
zookeeper-servers:
- host: {zookeeper_host}
port: {zookeeper_port}
chroot: {zookeeper_chroot}
labels: []
providers: []
diskimages:
- name: fake-image
build-timeout: 2
formats:
- tar
elements:
- fedora
- vm
release: 21
env-vars:
TMPDIR: /opt/dib_tmp
DIB_IMAGE_CACHE: /opt/dib_cache
DIB_CLOUD_IMAGES: http://download.fedoraproject.org/pub/fedora/linux/releases/test/21-Beta/Cloud/Images/x86_64/
BASE_IMAGE_FILE: Fedora-Cloud-Base-20141029-21_Beta.x86_64.qcow2

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@ -16,6 +16,7 @@
import os
import uuid
import fixtures
import mock
from nodepool import builder, exceptions, tests
from nodepool.driver.fake import provider as fakeprovider
@ -335,3 +336,10 @@ class TestNodePoolBuilder(tests.DBTestCase):
self.assertEqual(build_default._formats, ['qcow2'])
self.assertEqual(build_vhd._formats, ['vhd'])
@mock.patch('select.poll')
def test_diskimage_build_timeout(self, mock_poll):
configfile = self.setup_config('diskimage_build_timeout.yaml')
builder.BUILD_PROCESS_POLL_TIMEOUT = 500
self.useBuilder(configfile, cleanup_interval=0)
self.waitForBuild('fake-image', '0000000001', states=(zk.FAILED,))

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@ -0,0 +1,6 @@
---
features:
- |
A new option (build-timeout) has been added to the builder diskimage
configuration to control how long the builder should wait for image
builds before giving up. The default is 8 hours.