Source code for airflow.providers.google.cloud.utils.bigquery

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from __future__ import annotations


[docs]def bq_cast(string_field: str, bq_type: str) -> None | int | float | bool | str:
    """
    Helper method that casts a BigQuery row to the appropriate data types.
    This is useful because BigQuery returns all fields as strings.
    """
    if string_field is None:
        return None
    elif bq_type == "INTEGER":
        return int(string_field)
    elif bq_type in ("FLOAT", "TIMESTAMP"):
        return float(string_field)
    elif bq_type == "BOOLEAN":
        if string_field not in ["true", "false"]:
            raise ValueError(f"{string_field} must have value 'true' or 'false'")
        return string_field == "true"
    else:
        return string_field