- eq = evqueue.get(True, 1)
- logging.info("%s %s" % (eq[1], eq[2]))
- newcollection = collection
- if eq[1] in ('add', 'update', 'create'):
- newcollection = eq[2]
- elif eq[1] == 'remove':
- newcollection = api.collections().list(filters=[["owner_uuid", "=", project]],
- limit=1,
- order='modified_at desc').execute()['items'][0]['uuid']
- if newcollection != collection:
- logging.info("restarting web service")
- collection = newcollection
- running = False
- except Queue.Empty:
- pass
- except (KeyboardInterrupt):
- logging.info("Got keyboard interrupt")
- ws.close()
- loop = False
- except Exception as e:
- logging.exception(str(e))
- ws.close()
- loop = False
+ try:
+ if collection:
+ if not args.image:
+ docker_image = None
+
+ # FUSE is asynchronous, so there is a race between
+ # the directory being updated above and the kernel
+ # cache being refreshed. This manifests as the
+ # bizare behavior where os.path.exists() returns
+ # True, but open() raises "file not found". The
+ # workaround is to keep trying until the kernel
+ # catches up.
+ while not docker_image and os.path.exists(os.path.join(mountdir, "docker_image")):
+ try:
+ with open(os.path.join(mountdir, "docker_image")) as di:
+ docker_image = di.read().strip()
+ except IOError as e:
+ pass
+
+ if not docker_image:
+ logger.error("Collection must contain a file 'docker_image' or must specify --image on the command line.")
+
+ if docker_image and ((docker_image != prev_docker_image) or cid is None):
+ if cid:
+ logger.info("Stopping Docker container")
+ subprocess.check_call(["docker", "stop", cid])
+ cid = None
+ docker_proc = None
+
+ if docker_image:
+ logger.info("Starting Docker container %s", docker_image)
+ ciddir = tempfile.mkdtemp()
+ cidfilepath = os.path.join(ciddir, "cidfile")
+ docker_proc = subprocess.Popen(["docker", "run",
+ "--cidfile=%s" % (cidfilepath),
+ "--publish=%i:80" % (port),
+ "--volume=%s:/mnt:ro" % mountdir,
+ docker_image])
+ cid = None
+ while not cid and docker_proc.poll() is None:
+ try:
+ with open(cidfilepath) as cidfile:
+ cid = cidfile.read().strip()
+ except IOError:
+ pass
+ try:
+ os.unlink(cidfilepath)
+ os.rmdir(ciddir)
+ except OSError:
+ pass
+
+ prev_docker_image = docker_image
+ logger.info("Container id %s", cid)
+ elif cid:
+ logger.info("Sending refresh signal to container")
+ # Send SIGHUP to all the processes inside the
+ # container. By convention, services are expected
+ # to reload their configuration. If they die
+ # instead, that's okay, because then we'll just
+ # start a new container.
+ #
+ # Getting the services inside the container to
+ # refresh turned out to be really hard. Here are
+ # some of the other things I tried:
+ #
+ # docker kill --signal=HUP # no effect
+ # docker_proc.send_signal(signal.SIGHUP) # no effect
+ # os.killpg(os.getpgid(docker_proc.pid), signal.SIGHUP) # docker-proxy dies as collatoral damage
+ # docker exec apache2ctl restart # only works if service is using apache.
+ # Sending HUP directly to the processes inside the container: permission denied
+
+ subprocess.check_call(["docker", "exec", cid, "killall", "--regexp", ".*", "--signal", "HUP"])
+ elif cid:
+ logger.info("Stopping docker container")
+ subprocess.check_call(["docker", "stop", cid])
+ except subprocess.CalledProcessError:
+ cid = None
+
+ if not cid:
+ logger.warning("No service running! Will wait for a new collection to appear in the project.")
+ else:
+ logger.info("Waiting for events")
+
+ running = True
+ loop = True
+ while running:
+ # Main run loop. Wait on project events, signals, or the
+ # Docker container stopping.
+
+ try:
+ # Poll the queue with a 1 second timeout, if we have no
+ # timeout the Python runtime doesn't have a chance to
+ # process SIGINT or SIGTERM.
+ eq = evqueue.get(True, 1)
+ logger.info("%s %s", eq[1], eq[2])
+ newcollection = collection
+ if eq[1] in ('add', 'update', 'create'):
+ newcollection = eq[2]
+ elif eq[1] == 'remove':
+ collections = api.collections().list(filters=[["owner_uuid", "=", project]],
+ limit=1,
+ order='modified_at desc').execute()['items']
+ newcollection = collections[0]['uuid'] if len(collections) > 0 else None
+ running = False
+ except Queue.Empty:
+ pass
+
+ if docker_proc and docker_proc.poll() is not None:
+ logger.warning("Service has terminated. Will try to restart.")
+ cid = None
+ docker_proc = None
+ running = False
+
+ except (KeyboardInterrupt):
+ logger.info("Got keyboard interrupt")
+ ws.close()
+ loop = False
+ except Exception as e:
+ logger.exception(e)
+ ws.close()
+ loop = False