work in progress for sharing

open_buildings/google/stac-geoparquet.py

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+# WARNING - Work in progress
+# This isn't working yet, but it's close. The main issue is that the catalog
+# and collections aren't getting formed right - I want them in the hive partitions, but
+# pystac keeps trying to move them in the recommended STAC structure. Committing in case 
+# its useful.
+# Next approach may just be to form the items individually, as that part seems to be fine,
+# and then place them in the catalog and collection manually (maybe pystac can help, but 
+# may be easier to just use python to adjust the links)
+
+
+import os
+import pystac
+from pystac import Catalog, Collection, Item, Asset, CatalogType
+import geopandas as gpd
+from datetime import datetime
+import click
+from shapely.geometry import box
+from dateutil.parser import parse
+
+def read_geoparquet_bounds(filepath):
+    """
+    Reads a Geoparquet file and returns its bounds and EPSG.
+    """
+    gdf = gpd.read_parquet(filepath)
+    bounds = gdf.total_bounds.tolist()
+    epsg = gdf.crs.to_epsg()  # Extract the EPSG code
+    return bounds, epsg
+
+def create_stac_item_for_geoparquet(filepath, collection, item_datetime):
+    filename = os.path.basename(filepath)
+    file_id, _ = os.path.splitext(filename)
+    title = filename
+
+    # Get the bounds and CRS
+    bbox, epsg = read_geoparquet_bounds(filepath)
+
+    # Use the bounds as the geometry too
+    geometry = box(*bbox).__geo_interface__
+
+    item = Item(id=file_id,
+                geometry=geometry, 
+                bbox=bbox,
+                datetime=item_datetime,
+                properties={'title': title, 'proj:epsg': epsg},
+                collection=collection.id)
+
+    pystac.extensions.projection.ProjectionExtension.add_to(item)
+    item.add_asset(key="data", asset=Asset(href=filepath, media_type="application/parquet"))
+
+    return item
+
+@click.command()
+@click.argument('directory', type=click.Path(exists=True))
+@click.option('--collection-path', default='collection.json', help='Path to the collection.json file relative to the directory.')
+@click.option('--item-datetime', default='2023-05-30T00:00:00Z', help='Datetime for the STAC items.')
+@click.option('--catalog-type', type=click.Choice(['SELF_CONTAINED', 'ABSOLUTE_PUBLISHED'], case_sensitive=False), default='SELF_CONTAINED', help='Type of the catalog.')
+@click.option('--root-path', default=None, help='Root path for the catalog. Relevant for ABSOLUTE_PUBLISHED catalog type.')
+# ... [other necessary imports and functions]
+
+def main(directory, collection_path, item_datetime, catalog_type, root_path):
+    catalog_id = 'my-catalog'
+    catalog_description = 'A catalog of geoparquet files.'
+    item_datetime = parse(item_datetime)
+    collection = Collection.from_file(collection_path)
+
+    # Create the catalog first
+    catalog = Catalog(id=catalog_id, description=catalog_description, catalog_type=CatalogType[catalog_type])
+
+    items = []
+    for root, _, files in os.walk(directory):
+        for filename in files:
+            if filename.endswith(".parquet"):
+                filepath = os.path.join(root, filename)
+                item = create_stac_item_for_geoparquet(filepath, collection, item_datetime)
+
+                # Save the item alongside the parquet file
+                item_path = os.path.join(root, f"{item.id}.json")
+                item.set_self_href(item_path)
+                item.save_object()
+                items.append(item)
+
+     # Create and save the catalog
+    catalog_path = os.path.join(directory, 'catalog.json')
+    catalog.set_self_href(catalog_path)
+    catalog.save_object()
+
+    # Reload the catalog from file
+    catalog = Catalog.from_file(catalog_path)
+
+    # Add items to the catalog
+    for item in items:
+        catalog.add_item(item)
+        item.add_link(pystac.Link("parent", os.path.relpath(catalog.get_self_href(), os.path.dirname(item.get_self_href()))))
+
+    # Save the updated catalog
+    catalog.save_object()
+
+    # Load the collection and set its links
+    collection_path_new = os.path.join(directory, "collection.json")
+    collection.set_self_href(collection_path_new)
+    collection.add_child(catalog)
+    collection.save_object()
+
+if __name__ == "__main__":
+    main()