def test_contains_long_hex_number(self):
"""Tests contains_long_hex_number()."""
self.assertFalse(utilities.contains_long_hex_number(''))
self.assertFalse(utilities.contains_long_hex_number('cluster-insight'))
self.assertFalse(utilities.contains_long_hex_number('abc-123'))
self.assertFalse(utilities.contains_long_hex_number(u'hello01234567'))
self.assertTrue(utilities.contains_long_hex_number(u'hello.01234567'))
self.assertTrue(utilities.contains_long_hex_number(
'k8s_php-redis.b317029a_guestbook-controller-ls6k1.default.api_'
'f991d53e-b949-11e4-8246-42010af0c3dd_8dcdfec8'))
def get_containers(gs, docker_host):
"""Gets the list of all containers in 'docker_host'.
Args:
gs: global state.
docker_host: the Docker host running the containers.
Returns:
list of wrapped container objects.
Each element in the list is the result of
utilities.wrap_object(container, 'Container', ...)
Raises:
CollectorError: in case of failure to fetch data from Docker.
Other exceptions may be raised due to exectution errors.
"""
containers, timestamp = gs.get_containers_cache().lookup(docker_host)
if timestamp is not None:
gs.logger_info(
'get_containers(docker_host=%s) cache hit returns '
'%d containers', docker_host, len(containers))
return containers
url = 'http://{docker_host}:{port}/containers/json'.format(
docker_host=docker_host, port=gs.get_docker_port())
# A typical value of 'docker_host' is:
# k8s-guestbook-node-3.c.rising-apricot-840.internal
# Use only the first period-seperated element for the test file name.
fname = '{host}-containers'.format(host=docker_host.split('.')[0])
try:
containers_list = fetch_data(gs, url, fname)
except collector_error.CollectorError:
raise
except:
msg = ('fetching %s or %s failed with exception %s' %
(url, fname, sys.exc_info()[0]))
gs.logger_exception(msg)
raise collector_error.CollectorError(msg)
if not isinstance(containers_list, types.ListType):
msg = 'invalid response from fetching %s' % url
gs.logger_exception(msg)
raise collector_error.CollectorError(msg)
containers = []
timestamps = []
for container_info in containers_list:
# NOTE: container 'Name' is stable across container re-starts whereas
# container 'Id' is not.
# This may be because Kubernertes assigns the Name while Docker assigns
# the Id (?)
# The container Name is the only element of the array 'Names' -
# why is Names an array here?
# skip the leading / in the Name
if not (isinstance(container_info.get('Names'), types.ListType) and
container_info['Names'] and
utilities.valid_string(container_info['Names'][0]) and
container_info['Names'][0][0] == '/'):
msg = 'invalid containers data format. docker_host=%s' % docker_host
gs.logger_error(msg)
raise collector_error.CollectorError(msg)
container_id = container_info['Names'][0][1:]
container, ts = _inspect_container(gs, docker_host, container_id)
if container is None:
continue
if not utilities.valid_string(container.get('Name')):
msg = ('missing or invalid "Name" attribute in container %s' %
container_id)
gs.logger_error(msg)
raise collector_error.CollectorError(msg)
if container['Name'] != ('/' + container_id):
msg = ('container %s\'s Name attribute is "%s"; expecting "%s"' %
(container_id, container['Name'], '/' + container_id))
gs.logger_error(msg)
raise collector_error.CollectorError(msg)
# The 'container_id' is most often unique, because it contains long
# unique hex numbers. However, in some cases the 'container_id' is simply
# the image name, such as "cluster-insight". In this case 'container_id'
# is not unique in the context graph, so we make it unique by appending
# the a prefix of the Docker ID of the container.
hex_id = utilities.object_to_hex_id(container)
if hex_id is None:
msg = 'Could not compute short hex ID of container %s' % container_id
gs.logger_error(msg)
raise collector_error.CollectorError(msg)
if utilities.contains_long_hex_number(container_id):
short_label = hex_id
unique_id = container_id
else:
# The short label is descriptive when 'container_id' does not contain
# long hex numbers.
short_label = container_id
unique_id = '{container_id}-{hex_id}'.format(
container_id=container_id, hex_id=hex_id)
wrapped_container = utilities.wrap_object(
container, 'Container', unique_id, ts, label=short_label)
containers.append(wrapped_container)
timestamps.append(ts)
# If the container's label does not contain long hex fields, it is
# good enough. It should not be replaced with anything else.
if not utilities.contains_long_hex_number(short_label):
continue
# Modify the container's label after the wrapped container was added
# to the containers list.
# Compute the container's short name to create a better container label:
# short_container_name/short_hex_id.
# For example: "cassandra/d85b599c17d8".
parent_pod_id = utilities.get_parent_pod_id(wrapped_container)
if parent_pod_id is None:
continue
parent_pod = kubernetes.get_one_pod(gs, docker_host, parent_pod_id)
if parent_pod is None:
continue
short_container_name = utilities.get_short_container_name(
wrapped_container, parent_pod)
if not utilities.valid_string(short_container_name):
continue
wrapped_container['annotations']['label'] = (short_container_name + '/' +
hex_id)
ret_value = gs.get_containers_cache().update(
docker_host, containers,
min(timestamps) if timestamps else time.time())
gs.logger_info(
'get_containers(docker_host=%s) returns %d containers',
docker_host, len(containers))
return ret_value
