When a table is loaded, its metadata properties are merged into the property map used to construct the table's FileIO, and they take precedence over the operator's catalog configuration.
Catalog._load_file_io computes:
load_file_io({**self.properties, **properties}, location)where properties is metadata.properties. Because table properties come last, a value stored in a table overrides the same key configured on the catalog. The REST path does the same at _response_to_table / _response_to_staged_table, and Glue, Hive, SQL, DynamoDB, BigQuery and StaticTable.from_metadata all funnel table metadata into FileIO construction the same way — 12 call sites in total.
The keys this reaches include implementation selection (py-io-impl, s3.retry-strategy-impl) and transport configuration (s3.endpoint, s3.proxy-uri, s3.signer / s3.signer.uri, gcs.service.host, hf.endpoint, the ADLS storage authorities). These are deployment concerns — an operator sets them on the catalog — but any principal who can commit to a table can currently override them for everyone who reads it.
Issue investigation generated via claude, reviewed by Sung, Kevin, Fokko.
When a table is loaded, its metadata properties are merged into the property map used to construct the table's
FileIO, and they take precedence over the operator's catalog configuration.Catalog._load_file_iocomputes:where
propertiesismetadata.properties. Because table properties come last, a value stored in a table overrides the same key configured on the catalog. The REST path does the same at_response_to_table/_response_to_staged_table, and Glue, Hive, SQL, DynamoDB, BigQuery andStaticTable.from_metadataall funnel table metadata intoFileIOconstruction the same way — 12 call sites in total.The keys this reaches include implementation selection (
py-io-impl,s3.retry-strategy-impl) and transport configuration (s3.endpoint,s3.proxy-uri,s3.signer/s3.signer.uri,gcs.service.host,hf.endpoint, the ADLS storage authorities). These are deployment concerns — an operator sets them on the catalog — but any principal who can commit to a table can currently override them for everyone who reads it.Issue investigation generated via claude, reviewed by Sung, Kevin, Fokko.