Source code for airflow.providers.cncf.kubernetes.template_rendering

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from __future__ import annotations

from typing import TYPE_CHECKING

from jinja2 import TemplateAssertionError, UndefinedError
from kubernetes.client.api_client import ApiClient

from airflow.exceptions import AirflowException
from airflow.providers.cncf.kubernetes.kube_config import KubeConfig
from airflow.providers.cncf.kubernetes.kubernetes_helper_functions import create_unique_id
from airflow.providers.cncf.kubernetes.pod_generator import PodGenerator
from airflow.utils.session import NEW_SESSION, provide_session

if TYPE_CHECKING:
    from airflow.models.taskinstance import TaskInstance



[docs]def render_k8s_pod_yaml(task_instance: TaskInstance) -> dict | None:
    """Render k8s pod yaml."""
    kube_config = KubeConfig()
    pod = PodGenerator.construct_pod(
        dag_id=task_instance.dag_id,
        run_id=task_instance.run_id,
        task_id=task_instance.task_id,
        map_index=task_instance.map_index,
        date=None,
        pod_id=create_unique_id(task_instance.dag_id, task_instance.task_id),
        try_number=task_instance.try_number,
        kube_image=kube_config.kube_image,
        args=task_instance.command_as_list(),
        pod_override_object=PodGenerator.from_obj(task_instance.executor_config),
        scheduler_job_id="0",
        namespace=kube_config.executor_namespace,
        base_worker_pod=PodGenerator.deserialize_model_file(kube_config.pod_template_file),
        with_mutation_hook=True,
    )
    sanitized_pod = ApiClient().sanitize_for_serialization(pod)
    return sanitized_pod



@provide_session

[docs]def get_rendered_k8s_spec(task_instance: TaskInstance, session=NEW_SESSION) -> dict | None:
    """Fetch rendered template fields from DB."""
    from airflow.models.renderedtifields import RenderedTaskInstanceFields

    rendered_k8s_spec = RenderedTaskInstanceFields.get_k8s_pod_yaml(task_instance, session=session)
    if not rendered_k8s_spec:
        try:
            rendered_k8s_spec = render_k8s_pod_yaml(task_instance)
        except (TemplateAssertionError, UndefinedError) as e:
            raise AirflowException(f"Unable to render a k8s spec for this taskinstance: {e}") from e
    return rendered_k8s_spec

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