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Source code for galaxy.containers.docker
"""
Interface to Docker
"""
from __future__ import absolute_import
import logging
import os
from functools import partial
from itertools import cycle, repeat
from time import sleep
try:
import docker
except ImportError:
docker = None
try:
from requests.exceptions import ConnectionError, ReadTimeout
except ImportError:
ConnectionError = None
ReadTimeout = None
from six import string_types
from six.moves import shlex_quote
from galaxy.containers import ContainerInterface
from galaxy.containers.docker_decorators import (
docker_columns,
docker_json
)
from galaxy.containers.docker_model import (
DockerContainer,
DockerVolume
)
from galaxy.exceptions import (
ContainerCLIError,
ContainerImageNotFound,
ContainerNotFound
)
from galaxy.util.json import safe_dumps_formatted
log = logging.getLogger(__name__)
[docs]class DockerInterface(ContainerInterface):
container_class = DockerContainer
volume_class = DockerVolume
conf_defaults = {
'host': None,
'tls': False,
'force_tlsverify': False,
'auto_remove': True,
'image': None,
'cpus': None,
'memory': None,
}
# These values are inserted into kwopts for run commands
conf_run_kwopts = (
'cpus',
'memory',
)
[docs] def validate_config(self):
super(DockerInterface, self).validate_config()
self.__host_iter = None
if self._conf.host is None or isinstance(self._conf.host, string_types):
self.__host_iter = repeat(self._conf.host)
else:
self.__host_iter = cycle(self._conf.host)
@property
def _default_image(self):
assert self._conf.image is not None, "No default image for this docker interface"
return self._conf.image
[docs] def run_in_container(self, command, image=None, **kwopts):
for opt in self.conf_run_kwopts:
if self._conf[opt]:
kwopts[opt] = self._conf[opt]
self.set_kwopts_name(kwopts)
return self.run(command, image=image, **kwopts)
[docs] def image_repodigest(self, image):
"""Get the digest image string for an image.
:type image: str
:param image: image id or image name and optionally, tag
:returns: digest string, having the format `<name>@<hash_alg>:<digest>`, e.g.:
`'bgruening/docker-jupyter-notebook@sha256:3ec0bc9abc9d511aa602ee4fff2534d80dd9b1564482de52cb5de36cce6debae'`
or, the original image name if the digest cannot be
determined (the image has not been pulled)
"""
try:
inspect = self.image_inspect(image)
return inspect['RepoDigests'][0]
except ContainerImageNotFound:
return image
@property
def host(self):
return self.__host_iter.next()
@property
def host_iter(self):
return self.__host_iter
[docs]class DockerCLIInterface(DockerInterface):
container_type = 'docker_cli'
conf_defaults = {
'command_template': '{executable} {global_kwopts} {subcommand} {args}',
'executable': 'docker',
}
option_map = {
# `run` options
'environment': {'flag': '--env', 'type': 'list_of_kvpairs'},
'volumes': {'flag': '--volume', 'type': 'docker_volumes'},
'name': {'flag': '--name', 'type': 'string'},
'detach': {'flag': '--detach', 'type': 'boolean'},
'publish_all_ports': {'flag': '--publish-all', 'type': 'boolean'},
'publish_port_random': {'flag': '--publish', 'type': 'string'},
'auto_remove': {'flag': '--rm', 'type': 'boolean'},
'cpus': {'flag': '--cpus', 'type': 'string'},
'memory': {'flag': '--memory', 'type': 'string'},
}
[docs] def validate_config(self):
log.warning('The `docker_cli` interface is deprecated and will be removed in Galaxy 18.09, please use `docker`')
super(DockerCLIInterface, self).validate_config()
global_kwopts = []
if self._conf.host:
global_kwopts.append('--host')
global_kwopts.append(shlex_quote(self._conf.host))
if self._conf.force_tlsverify:
global_kwopts.append('--tlsverify')
self._docker_command = self._conf['command_template'].format(
executable=self._conf['executable'],
global_kwopts=' '.join(global_kwopts),
subcommand='{subcommand}',
args='{args}'
)
def _filter_by_id_or_name(self, id, name):
if id:
return '--filter id={}'.format(id)
elif name:
return '--filter name={}'.format(name)
return None
def _stringify_kwopt_docker_volumes(self, flag, val):
"""The docker API will take a volumes argument in many formats, try to
deal with that for the command line
"""
l = []
if isinstance(val, list):
# ['/host/vol']
l = val
else:
for hostvol, guestopts in val.items():
if isinstance(guestopts, string_types):
# {'/host/vol': '/container/vol'}
l.append('{}:{}'.format(hostvol, guestopts))
else:
# {'/host/vol': {'bind': '/container/vol'}}
# {'/host/vol': {'bind': '/container/vol', 'mode': 'rw'}}
mode = guestopts.get('mode', '')
l.append('{vol}:{bind}{mode}'.format(
vol=hostvol,
bind=guestopts['bind'],
mode=':' + mode if mode else ''
))
return self._stringify_kwopt_list(flag, l)
def _run_docker(self, subcommand, args=None, verbose=False):
command = self._docker_command.format(subcommand=subcommand, args=args or '')
return self._run_command(command, verbose=verbose)
#
# docker subcommands
#
[docs] @docker_columns
def ps(self, id=None, name=None):
return self._run_docker(subcommand='ps', args=self._filter_by_id_or_name(id, name))
[docs] def run(self, command, image=None, **kwopts):
args = '{kwopts} {image} {command}'.format(
kwopts=self._stringify_kwopts(kwopts),
image=image or self._default_image,
command=command if command else ''
).strip()
container_id = self._run_docker(subcommand='run', args=args, verbose=True)
return DockerContainer.from_id(self, container_id)
[docs] @docker_json
def inspect(self, container_id):
try:
return self._run_docker(subcommand='inspect', args=container_id)[0]
except (IndexError, ContainerCLIError) as exc:
msg = "Invalid container id: %s" % container_id
if exc.stdout == '[]' and exc.stderr == 'Error: no such object: {container_id}'.format(container_id=container_id):
log.warning(msg)
return []
else:
raise ContainerNotFound(msg, container_id=container_id)
[docs] @docker_json
def image_inspect(self, image):
try:
return self._run_docker(subcommand='image inspect', args=image)[0]
except (IndexError, ContainerCLIError) as exc:
msg = "%s not pulled, cannot get digest" % image
if exc.stdout == '[]' and exc.stderr == 'Error: no such image: {image}'.format(image=image):
log.warning(msg, image)
return []
else:
raise ContainerImageNotFound(msg, image=image)
[docs]class DockerAPIClient(object):
"""Wraps a ``docker.APIClient`` to catch exceptions.
"""
_exception_retry_time = 5
_default_max_tries = 10
_host_iter = None
_client = None
_client_args = ()
_client_kwargs = {}
@staticmethod
def _qualname(f):
if isinstance(f, partial):
f = f.func
try:
return getattr(f, '__qualname__', f.im_class.__name__ + '.' + f.__name__)
except AttributeError:
return f.__name__
@staticmethod
def _should_retry_request(response_code):
return response_code >= 500 or response_code in (404, 408, 409, 429)
@staticmethod
def _nonfatal_error(response_code):
return response_code in (404,)
@staticmethod
def _unwrapped_attr(attr):
return getattr(DockerAPIClient._client, attr)
@staticmethod
def _init_client():
kwargs = DockerAPIClient._client_kwargs.copy()
if DockerAPIClient._host_iter is not None and 'base_url' not in kwargs:
kwargs['base_url'] = DockerAPIClient._host_iter.next()
DockerAPIClient._client = docker.APIClient(*DockerAPIClient._client_args, **kwargs)
log.info('Initialized Docker API client for server: %s', kwargs.get('base_url', 'localhost'))
@staticmethod
def _default_client_handler(fname, *args, **kwargs):
success_test = kwargs.pop('success_test', None)
max_tries = kwargs.pop('max_tries', DockerAPIClient._default_max_tries)
for tries in range(1, max_tries + 1):
retry_time = DockerAPIClient._exception_retry_time
reinit = False
exc = None
# re-get the APIClient method every time as a different caller (such as the success test function) may have
# already reinitialized the client, and we always want to use the current client
f = DockerAPIClient._unwrapped_attr(fname)
qualname = DockerAPIClient._qualname(f)
try:
r = f(*args, **kwargs)
if tries > 1:
log.info('%s() succeeded on attempt %s', qualname, tries)
return r
except ConnectionError:
reinit = True
except docker.errors.APIError as exc:
if not DockerAPIClient._should_retry_request(exc.response.status_code):
raise
except ReadTimeout:
reinit = True
retry_time = 0
finally:
# this is inside the finally context so we can do a bare raise when we give up (so the real stack for
# the exception is raised)
if exc is not None:
log.warning("Caught exception on %s(): %s: %s",
DockerAPIClient._qualname(f), exc.__class__.__name__, exc)
if reinit:
log.warning("Reinitializing Docker API client due to connection-oriented failure")
DockerAPIClient._init_client()
f = DockerAPIClient._unwrapped_attr(fname)
qualname = DockerAPIClient._qualname(f)
r = None
if success_test is not None:
log.info("Testing if %s() succeeded despite the exception", qualname)
r = success_test()
if r:
log.warning("The request appears to have succeeded, will not retry. Response is: %s", str(r))
return r
elif tries >= max_tries:
log.error("Maximum number of attempts (%s) exceeded", max_tries)
if 'response' in exc and DockerAPIClient._nonfatal_error(exc.response.status_code):
return None
else:
raise
else:
log.error("Retrying %s() in %s seconds (attempt: %s of %s)", qualname, retry_time, tries,
max_tries)
sleep(retry_time)
[docs] def __init__(self, *args, **kwargs):
# Only initialize the host iterator once
host_iter = kwargs.pop('host_iter', None)
DockerAPIClient._host_iter = DockerAPIClient._host_iter or host_iter
DockerAPIClient._client_args = args
DockerAPIClient._client_kwargs = kwargs
DockerAPIClient._init_client()
def __getattr__(self, attr):
"""Allow the calling of methods on this class as if it were a docker.APIClient instance.
"""
cattr = DockerAPIClient._unwrapped_attr(attr)
if callable(cattr):
return partial(DockerAPIClient._default_client_handler, attr)
else:
return cattr
[docs]class DockerAPIInterface(DockerInterface):
container_type = 'docker'
# 'publish_port_random' and 'volumes' are special cases handled in _create_host_config()
host_config_option_map = {
'auto_remove': {},
'publish_all_ports': {},
'cpus': {'param': 'nano_cpus', 'map': lambda x: int(x * 1000000000)},
'memory': {'param': 'mem_limit'},
'binds': {},
'port_bindings': {},
}
[docs] def validate_config(self):
assert docker is not None, "Docker module could not be imported, DockerAPIInterface unavailable"
super(DockerAPIInterface, self).validate_config()
self.__client = None
@property
def _client(self):
# TODO: add cert options to containers conf
cert_path = os.environ.get('DOCKER_CERT_PATH') or None
if not cert_path:
cert_path = os.path.join(os.path.expanduser('~'), '.docker')
if self._conf.force_tlsverify or self._conf.tls:
tls_config = docker.tls.TLSConfig(
client_cert=(os.path.join(cert_path, 'cert.pem'),
os.path.join(cert_path, 'key.pem')),
ca_cert=os.path.join(cert_path, 'ca.pem'),
verify=self._conf.force_tlsverify,
)
else:
tls_config = False
if not self.__client:
self.__client = DockerAPIClient(
host_iter=self.host_iter,
tls=tls_config,
)
return self.__client
@staticmethod
def _first(f, *args, **kwargs):
try:
return f(*args, **kwargs)[0]
except IndexError:
return None
@staticmethod
def _filter_by_id_or_name(id, name):
if id:
return {'id': id}
elif name:
return {'name': name}
return None
@staticmethod
def _kwopt_to_param_names(map_spec, key):
"""For a given containers lib method parameter name, return the matching docker-py parameter name(s).
See :meth:`_create_docker_api_spec`.
"""
params = []
if 'param' not in map_spec and 'params' not in map_spec:
params.append(key)
elif 'param' in map_spec:
params.append(map_spec['param'])
params.extend(map_spec.get('params', ()))
return params
@staticmethod
def _kwopt_to_params(map_spec, key, value):
"""For a given containers lib method parameter name and value, return the matching docker-py parameters with
values set (including transformation with an optional map function).
See :meth:`_create_docker_api_spec`.
"""
params = {}
if 'map' in map_spec:
value = map_spec['map'](value)
for param in DockerAPIInterface._kwopt_to_param_names(map_spec, key):
params[param] = value
return params
def _create_docker_api_spec(self, option_map_name, spec_class, kwopts):
"""Create docker-py objects used as arguments to docker-py methods.
This method modifies ``kwopts`` by removing options that match the spec.
An option map is a class-level variable with name ``<map_name>_option_map`` and is a dict with format:
.. code-block:: python
sample_option_map = {
'containers_lib_option_name': {
'param': docker_lib_positional_argument_int or 'docker_lib_keyword_argument_name',
'params': like 'param' but an iterable containing multiple docker lib params to set,
'default': default value,
'map': function with with to transform the value,
'required': True if this param is required, else False (default),
},
'_spec_param': {
'spec_class': class of param value,
}
}
All members of the mapping value are optional.
For example, a spec map for (some of) the possible values of the :class:`docker.types.TaskTemplate`, which is
used as the ``task_template`` argument to :meth:`docker.APIClient.create_service`, and the possible values of
the :class`:docker.types.ContainerSpec`, which is used as the ``container_spec`` argument to the
``TaskTemplate`` would be:
.. code-block:: python
task_template_option_map = {
# TaskTemplate's 'container_spec' param is a ContainerSpec
'_container_spec': {
'spec_class': docker.types.ContainerSpec,
'required': True
}
}
container_spec_option_map = {
'image': {'param': 0}, # positional argument 0 to ContainerSpec()
'command': {}, # 'command' keyword argument to ContainerSpec()
'environment': { # 'env' keyword argument to ContainerSpec(), 'environment' keyword argument
'param': 'env' # to ContainerInterface.run_in_container()
},
}
Thus, calling ``DockerInterface.run_in_contaner('true', image='busybox', environment={'FOO': 'foo'}`` will
essentially do this (for example, if using Docker Swarm mode):
.. code-block:: python
container_spec = docker.types.ContainerSpec('busybox', command='true', env={'FOO': 'foo'})
task_template = docker.types.TaskTemplate(container_spec=container_spec)
docker.APIClient().create_service(task_template)
:param option_map_name: Name of option map class variable (``_option_map`` is automatically appended)
:type option_map_name: str
:param spec_class: docker-py specification class or callable returning an instance
:type spec_class: :class:`docker.types.Resources`, :class:`docker.types.ContainerSpec`, etc. or
callable
:param kwopts: Keyword options passed to calling method (e.g.
:meth:`DockerInterface.run_in_container`)
:type kwopts: dict
:returns: Instantiated ``spec_class`` object
:rtype: ``type(spec_class)``
"""
def _kwopt_to_arg(map_spec, key, value, param=None):
# determines whether the given param is a positional or keyword argument in docker-py and adds it to the
# list of arguments
if isinstance(map_spec.get('param'), int):
spec_opts.append((map_spec.get('param'), value))
elif param is not None:
spec_kwopts[param] = value
else:
spec_kwopts.update(DockerAPIInterface._kwopt_to_params(map_spec, key, value))
# positional arguments
spec_opts = []
# keyword arguments
spec_kwopts = {}
# retrieve the option map for the docker-py object we're creating
option_map = getattr(self, option_map_name + '_option_map')
# set defaults
for key in filter(lambda k: option_map[k].get('default'), option_map.keys()):
map_spec = option_map[key]
_kwopt_to_arg(map_spec, key, map_spec['default'])
# don't allow kwopts that start with _, those are reserved for "child" object params
for kwopt in filter(lambda k: not k.startswith('_') and k in option_map, kwopts.keys()):
map_spec = option_map[kwopt]
_v = kwopts.pop(kwopt)
_kwopt_to_arg(map_spec, kwopt, _v)
# find any child objects that need to be created and recurse to create them
for _sub_k in filter(lambda k: k.startswith('_') and 'spec_class' in option_map[k], option_map.keys()):
map_spec = option_map[_sub_k]
param = _sub_k.lstrip('_')
_sub_v = self._create_docker_api_spec(param, map_spec['spec_class'], kwopts)
if _sub_v is not None or map_spec.get('required') or isinstance(map_spec.get('param'), int):
_kwopt_to_arg(map_spec, None, _sub_v, param=param)
# sort positional args and make into a flat tuple
if spec_opts:
spec_opts = sorted(spec_opts, key=lambda x: x[0])
spec_opts = [i[1] for i in spec_opts]
# create spec object
if spec_opts or spec_kwopts:
return spec_class(*spec_opts, **spec_kwopts)
else:
return None
def _volumes_to_native(self, volumes):
"""Convert a list of volume definitions to the docker-py container creation method parameters.
:param volumes: List of volumes to translate
:type volumes: list of :class:`galaxy.containers.docker_model.DockerVolume`s
"""
paths = []
binds = {}
for v in volumes:
path, bind = v.to_native()
paths.append(path)
binds.update(bind)
return (paths, binds)
def _create_host_config(self, kwopts):
"""Build the host configuration parameter for docker-py container creation.
This method modifies ``kwopts`` by removing host config options and potentially setting the ``ports`` and
``volumes`` keys.
:param kwopts: Keyword options passed to calling method (e.g. :method:`DockerInterface.run()`)
:type kwopts: dict
:returns: The return value of `docker.APIClient.create_host_config()`
:rtype: dict
"""
if 'publish_port_random' in kwopts:
port = int(kwopts.pop('publish_port_random'))
kwopts['port_bindings'] = {port: None}
kwopts['ports'] = [port]
if 'volumes' in kwopts:
paths, binds = self._volumes_to_native(kwopts.pop('volumes'))
kwopts['binds'] = binds
kwopts['volumes'] = paths
return self._create_docker_api_spec('host_config', self._client.create_host_config, kwopts)
#
# docker subcommands
#
[docs] def ps(self, id=None, name=None, running=True):
return self._client.containers(all=not running, filters=self._filter_by_id_or_name(id, name))
[docs] def run(self, command, image=None, **kwopts):
image = image or self._default_image
command = command or None
log.debug("Creating docker container with image '%s' for command: %s", image, command)
host_config = self._create_host_config(kwopts)
log.debug("Docker container host configuration:\n%s", safe_dumps_formatted(host_config))
log.debug("Docker container creation parameters:\n%s", safe_dumps_formatted(kwopts))
success_test = partial(self._first, self.ps, name=kwopts['name'], running=False)
# this can raise exceptions, if necessary we could wrap them in a more generic "creation failed" exception class
container = self._client.create_container(
image,
command=command if command else None,
host_config=host_config,
success_test=success_test,
max_tries=5,
**kwopts
)
container_id = container.get('Id')
log.debug("Starting container: %s (%s)", kwopts['name'], str(container_id))
# start can safely be run more than once
self._client.start(container=container_id)
return DockerContainer.from_id(self, container_id)
[docs] def inspect(self, container_id):
try:
return self._client.inspect_container(container_id)
except docker.errors.NotFound:
raise ContainerNotFound("Invalid container id: %s" % container_id, container_id=container_id)
[docs] def image_inspect(self, image):
try:
return self._client.inspect_image(image)
except docker.errors.NotFound:
raise ContainerImageNotFound("%s not pulled, cannot get digest" % image, image=image)