Summary
Adds an optional write_mode configuration to the BigQuery source,
enhancing security by controlling the types of SQL statements that can
be executed to prevent unauthorized data modification.
Key Changes
Added writeMode Configuration: A new write_mode field is added to the
BigQuery source, supporting three modes:
allowed (Default): Permits all SQL statements.
blocked: Allows only SELECT queries.
protected: Enables session-based execution, restricting write operations
(like CREATE TABLE) to the session's temporary dataset, thus protecting
permanent datasets. Note: at the moment, this won't work with
useClientOAuth, will fix this in the future.
These restrictions primarily apply to the bigquery-execute-sql tool and
the session may be used in other tools.
