Write to Parquet with GeoParquet 1.1 metadata (#40)

* Write to Parquet with GeoParquet 1.1 metadata

pyproject.toml

@@ -69,6 +69,7 @@ module = [
     "pandas.*",
     "pyarrow.*",
     "pypgstac.*",
+    "pyproj.*",
     "rich.*",
     "shapely.*",
     "tqdm.*",
@@ -78,4 +79,4 @@ ignore_missing_imports = true
 
 [[tool.mypy.overrides]]
 module = "stac_geoparquet.*"
-disallow_untyped_defs = true
+disallow_untyped_defs = true

stac_geoparquet/to_parquet.py

@@ -0,0 +1,46 @@
+import json
+from typing import Any
+
+import pyarrow as pa
+import pyarrow.parquet as pq
+from pyproj import CRS
+
+WGS84_CRS_JSON = CRS.from_epsg(4326).to_json_dict()
+
+
+def to_parquet(table: pa.Table, where: Any, **kwargs: Any) -> None:
+    """Write an Arrow table with STAC data to GeoParquet
+
+    This writes metadata compliant with GeoParquet 1.1.
+
+    Args:
+        table: The table to write to Parquet
+        where: The destination for saving.
+    """
+    # TODO: include bbox of geometries
+    column_meta = {
+        "encoding": "WKB",
+        # TODO: specify known geometry types
+        "geometry_types": [],
+        "crs": WGS84_CRS_JSON,
+        "edges": "planar",
+        "covering": {
+            "bbox": {
+                "xmin": ["bbox", "xmin"],
+                "ymin": ["bbox", "ymin"],
+                "xmax": ["bbox", "xmax"],
+                "ymax": ["bbox", "ymax"],
+            }
+        },
+    }
+    geo_meta = {
+        "version": "1.1.0-dev",
+        "columns": {"geometry": column_meta},
+        "primary_column": "geometry",
+    }
+
+    metadata = table.schema.metadata or {}
+    metadata.update({b"geo": json.dumps(geo_meta).encode("utf-8")})
+    table = table.replace_schema_metadata(metadata)
+
+    pq.write_table(table, where, **kwargs)