Source code for airflow.operators.docker_operator

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import json

from airflow.hooks.docker_hook import DockerHook
from airflow.exceptions import AirflowException
from airflow.models import BaseOperator
from airflow.utils.decorators import apply_defaults
from airflow.utils.file import TemporaryDirectory
from docker import APIClient, tls
import ast


[docs]class DockerOperator(BaseOperator): """ Execute a command inside a docker container. A temporary directory is created on the host and mounted into a container to allow storing files that together exceed the default disk size of 10GB in a container. The path to the mounted directory can be accessed via the environment variable ``AIRFLOW_TMP_DIR``. If a login to a private registry is required prior to pulling the image, a Docker connection needs to be configured in Airflow and the connection ID be provided with the parameter ``docker_conn_id``. :param image: Docker image from which to create the container. :type image: str :param api_version: Remote API version. Set to ``auto`` to automatically detect the server's version. :type api_version: str :param command: Command to be run in the container. (templated) :type command: str or list :param cpus: Number of CPUs to assign to the container. This value gets multiplied with 1024. See https://docs.docker.com/engine/reference/run/#cpu-share-constraint :type cpus: float :param docker_url: URL of the host running the docker daemon. Default is unix://var/run/docker.sock :type docker_url: str :param environment: Environment variables to set in the container. (templated) :type environment: dict :param force_pull: Pull the docker image on every run. Default is false. :type force_pull: bool :param mem_limit: Maximum amount of memory the container can use. Either a float value, which represents the limit in bytes, or a string like ``128m`` or ``1g``. :type mem_limit: float or str :param network_mode: Network mode for the container. :type network_mode: str :param tls_ca_cert: Path to a PEM-encoded certificate authority to secure the docker connection. :type tls_ca_cert: str :param tls_client_cert: Path to the PEM-encoded certificate used to authenticate docker client. :type tls_client_cert: str :param tls_client_key: Path to the PEM-encoded key used to authenticate docker client. :type tls_client_key: str :param tls_hostname: Hostname to match against the docker server certificate or False to disable the check. :type tls_hostname: str or bool :param tls_ssl_version: Version of SSL to use when communicating with docker daemon. :type tls_ssl_version: str :param tmp_dir: Mount point inside the container to a temporary directory created on the host by the operator. The path is also made available via the environment variable ``AIRFLOW_TMP_DIR`` inside the container. :type tmp_dir: str :param user: Default user inside the docker container. :type user: int or str :param volumes: List of volumes to mount into the container, e.g. ``['/host/path:/container/path', '/host/path2:/container/path2:ro']``. :param working_dir: Working directory to set on the container (equivalent to the -w switch the docker client) :type working_dir: str :param xcom_push: Does the stdout will be pushed to the next step using XCom. The default is False. :type xcom_push: bool :param xcom_all: Push all the stdout or just the last line. The default is False (last line). :type xcom_all: bool :param docker_conn_id: ID of the Airflow connection to use :type docker_conn_id: str """ template_fields = ('command', 'environment',) template_ext = ('.sh', '.bash',) @apply_defaults def __init__( self, image, api_version=None, command=None, cpus=1.0, docker_url='unix://var/run/docker.sock', environment=None, force_pull=False, mem_limit=None, network_mode=None, tls_ca_cert=None, tls_client_cert=None, tls_client_key=None, tls_hostname=None, tls_ssl_version=None, tmp_dir='/tmp/airflow', user=None, volumes=None, working_dir=None, xcom_push=False, xcom_all=False, docker_conn_id=None, *args, **kwargs): super(DockerOperator, self).__init__(*args, **kwargs) self.api_version = api_version self.command = command self.cpus = cpus self.docker_url = docker_url self.environment = environment or {} self.force_pull = force_pull self.image = image self.mem_limit = mem_limit self.network_mode = network_mode self.tls_ca_cert = tls_ca_cert self.tls_client_cert = tls_client_cert self.tls_client_key = tls_client_key self.tls_hostname = tls_hostname self.tls_ssl_version = tls_ssl_version self.tmp_dir = tmp_dir self.user = user self.volumes = volumes or [] self.working_dir = working_dir self.xcom_push_flag = xcom_push self.xcom_all = xcom_all self.docker_conn_id = docker_conn_id self.shm_size = kwargs.get('shm_size') self.cli = None self.container = None def get_hook(self): return DockerHook( docker_conn_id=self.docker_conn_id, base_url=self.docker_url, version=self.api_version, tls=self.__get_tls_config() ) def execute(self, context): self.log.info('Starting docker container from image %s', self.image) tls_config = self.__get_tls_config() if self.docker_conn_id: self.cli = self.get_hook().get_conn() else: self.cli = APIClient( base_url=self.docker_url, version=self.api_version, tls=tls_config ) if ':' not in self.image: image = self.image + ':latest' else: image = self.image if self.force_pull or len(self.cli.images(name=image)) == 0: self.log.info('Pulling docker image %s', image) for l in self.cli.pull(image, stream=True): output = json.loads(l.decode('utf-8')) self.log.info("%s", output['status']) cpu_shares = int(round(self.cpus * 1024)) with TemporaryDirectory(prefix='airflowtmp') as host_tmp_dir: self.environment['AIRFLOW_TMP_DIR'] = self.tmp_dir self.volumes.append('{0}:{1}'.format(host_tmp_dir, self.tmp_dir)) self.container = self.cli.create_container( command=self.get_command(), cpu_shares=cpu_shares, environment=self.environment, host_config=self.cli.create_host_config( binds=self.volumes, network_mode=self.network_mode, shm_size=self.shm_size), image=image, mem_limit=self.mem_limit, user=self.user, working_dir=self.working_dir ) self.cli.start(self.container['Id']) line = '' for line in self.cli.logs(container=self.container['Id'], stream=True): line = line.strip() if hasattr(line, 'decode'): line = line.decode('utf-8') self.log.info(line) exit_code = self.cli.wait(self.container['Id']) if exit_code != 0: raise AirflowException('docker container failed') if self.xcom_push_flag: return self.cli.logs(container=self.container['Id']) \ if self.xcom_all else str(line) def get_command(self): if self.command is not None and self.command.strip().find('[') == 0: commands = ast.literal_eval(self.command) else: commands = self.command return commands def on_kill(self): if self.cli is not None: self.log.info('Stopping docker container') self.cli.stop(self.container['Id']) def __get_tls_config(self): tls_config = None if self.tls_ca_cert and self.tls_client_cert and self.tls_client_key: tls_config = tls.TLSConfig( ca_cert=self.tls_ca_cert, client_cert=(self.tls_client_cert, self.tls_client_key), verify=True, ssl_version=self.tls_ssl_version, assert_hostname=self.tls_hostname ) self.docker_url = self.docker_url.replace('tcp://', 'https://') return tls_config