[SEDONA-455] Add a new data source namely geoparquet.metadata

• Type: New Feature
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.5.1
• Labels: pull-request-available
• Assignee: Unassigned Assign to me
• Reporter: Jia Yu
• Created: 27/Dec/23 07:05
• Updated: 13/Jan/24 23:54
• Resolved: 13/Jan/24 23:54

Description

Can we add a new data source to only read the file level metadata of a parquet file? This is crucial for entry-level users to explore an unknown parquet file including geoparquet. In our geoparquet case, this will help user know the projjson value since we are not able to properly parse it to a known epsg code.

I understand that a Spark DataFrame only allows the schema to be the metadata, which cannot be used to hold such information.

So I suggest that we add a new data source namely geoparquet.metadata, which loads these metadata using ParquetFileReader (https://github.com/apache/parquet-mr/blob/master/parquet-hadoop/src/main/java/org/apache/parquet/hadoop/ParquetFileReader.java). One good example is from DuckDB: duckdb.org/docs/data/parquet/metadata.html

Issue Links

• links to: GitHub Pull Request #1180