Skip to content

Geoparquet loader

Geoparquet loader.

This module contains geoparquet loader implementation.

GeoparquetLoader

Bases: Loader

GeoparquetLoader.

Geoparquet [1] loader is a wrapper for a geopandas.read_parquet function and allows for an automatic index setting and additional geometry clipping.

References
  1. https://github.com/opengeospatial/geoparquet

load(file_path, index_column=None, columns=None, area=None)

Load a geoparquet file.

PARAMETER DESCRIPTION
file_path

parquet file path.

TYPE: Union[Path, str]

index_column

Column that will be used as an index. If not provided, automatic indexing will be applied by default. Defaults to None.

TYPE: str DEFAULT: None

columns

List of columns to load. If not provided, all will be loaded. Defaults to None.

TYPE: List[str] DEFAULT: None

area

Mask to clip loaded data. If not provided, unaltered data will be returned. Defaults to None.

TYPE: GeoDataFrame DEFAULT: None

RAISES DESCRIPTION
ValueError

If provided index column doesn't exists in list of loaded columns.
RETURNS DESCRIPTION
GeoDataFrame

gpd.GeoDataFrame: Loaded geoparquet file as a GeoDataFrame.
Source code in srai/loaders/geoparquet_loader.py 
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
def load(
    self,
    file_path: Union[Path, str],
    index_column: Optional[str] = None,
    columns: Optional[list[str]] = None,
    area: Optional[gpd.GeoDataFrame] = None,
) -> gpd.GeoDataFrame:
    """
    Load a geoparquet file.

    Args:
        file_path (Union[Path, str]): parquet file path.
        index_column (str, optional): Column that will be used as an index.
            If not provided, automatic indexing will be applied by default. Defaults to None.
        columns (List[str], optional): List of columns to load.
            If not provided, all will be loaded. Defaults to None.
        area (gpd.GeoDataFrame, optional): Mask to clip loaded data.
            If not provided, unaltered data will be returned. Defaults to None.

    Raises:
        ValueError: If provided index column doesn't exists in list of loaded columns.

    Returns:
        gpd.GeoDataFrame: Loaded geoparquet file as a GeoDataFrame.
    """
    if columns and GEOMETRY_COLUMN not in columns:
        columns.append(GEOMETRY_COLUMN)

    gdf = gpd.read_parquet(path=file_path, columns=columns)

    if index_column:
        if index_column not in gdf.columns:
            raise ValueError(f"Column {index_column} doesn't exist in a file.")
        gdf.set_index(index_column, inplace=True)

    gdf.to_crs(crs=WGS84_CRS, inplace=True)

    if area is not None:
        area_wgs84 = area.to_crs(crs=WGS84_CRS)
        gdf = gdf.clip(mask=area_wgs84, keep_geom_type=False)

    return gdf