Source code for airflow.providers.amazon.aws.sensors.dynamodb

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from __future__ import annotations

from typing import TYPE_CHECKING, Any, Sequence

from airflow.compat.functools import cached_property
from airflow.providers.amazon.aws.hooks.dynamodb import DynamoDBHook
from airflow.sensors.base import BaseSensorOperator

if TYPE_CHECKING:
    from airflow.utils.context import Context


[docs]class DynamoDBValueSensor(BaseSensorOperator):
    """
    Waits for an attribute value to be present for an item in a DynamoDB table.

    .. seealso::
        For more information on how to use this sensor, take a look at the guide:
        :ref:`howto/sensor:DynamoDBValueSensor`

    :param table_name: DynamoDB table name
    :param partition_key_name: DynamoDB partition key name
    :param partition_key_value: DynamoDB partition key value
    :param attribute_name: DynamoDB attribute name
    :param attribute_value: DynamoDB attribute value
    :param sort_key_name: (optional) DynamoDB sort key name
    :param sort_key_value: (optional) DynamoDB sort key value
    :param aws_conn_id: aws connection to use
    :param region_name: aws region to use
    """

[docs]    template_fields: Sequence[str] = (
        "table_name",
        "partition_key_name",
        "partition_key_value",
        "attribute_name",
        "attribute_value",
        "sort_key_name",
        "sort_key_value",
    )

    def __init__(
        self,
        table_name: str,
        partition_key_name: str,
        partition_key_value: str,
        attribute_name: str,
        attribute_value: str,
        sort_key_name: str | None = None,
        sort_key_value: str | None = None,
        aws_conn_id: str | None = DynamoDBHook.default_conn_name,
        region_name: str | None = None,
        **kwargs: Any,
    ):
        super().__init__(**kwargs)
        self.table_name = table_name
        self.partition_key_name = partition_key_name
        self.partition_key_value = partition_key_value
        self.attribute_name = attribute_name
        self.attribute_value = attribute_value
        self.sort_key_name = sort_key_name
        self.sort_key_value = sort_key_value
        self.aws_conn_id = aws_conn_id
        self.region_name = region_name

[docs]    def poke(self, context: Context) -> bool:
        """Test DynamoDB item for matching attribute value"""
        key = {self.partition_key_name: self.partition_key_value}
        msg = (
            f"Checking table {self.table_name} for "
            + f"item Partition Key: {self.partition_key_name}={self.partition_key_value}"
        )

        if self.sort_key_name and self.sort_key_value:
            key = {self.partition_key_name: self.partition_key_value, self.sort_key_name: self.sort_key_value}
            msg += f"\nSort Key: {self.sort_key_name}={self.sort_key_value}"

        msg += f"\nattribute: {self.attribute_name}={self.attribute_value}"

        self.log.info(msg)
        table = self.hook.conn.Table(self.table_name)
        self.log.info("Table: %s", table)
        self.log.info("Key: %s", key)
        response = table.get_item(Key=key)
        try:
            self.log.info("Response: %s", response)
            self.log.info("Want: %s = %s", self.attribute_name, self.attribute_value)
            self.log.info(
                "Got: {response['Item'][self.attribute_name]} = %s", response["Item"][self.attribute_name]
            )
            return response["Item"][self.attribute_name] == self.attribute_value
        except KeyError:
            return False

    @cached_property
[docs]    def hook(self) -> DynamoDBHook:
        """Create and return a DynamoDBHook"""
        return DynamoDBHook(self.aws_conn_id, region_name=self.region_name)