Add paths method for getting multiple paths

benchmarks/benchmarks.py

@@ -12,6 +12,7 @@
 from hipscat.catalog import Catalog, PartitionInfo
 from hipscat.catalog.association_catalog.partition_join_info import PartitionJoinInfo
 from hipscat.catalog.catalog_info import CatalogInfo
+from hipscat.io.paths import pixel_catalog_files
 from hipscat.pixel_math import HealpixPixel
 from hipscat.pixel_tree import PixelAlignment, align_trees
 from hipscat.pixel_tree.pixel_tree_builder import PixelTreeBuilder
@@ -55,6 +56,9 @@ def setup(self):
     def time_pixel_tree_creation(self):
         PixelTreeBuilder.from_healpix(self.pixel_list)
 
+    def time_paths_creation(self):
+        pixel_catalog_files("foo/", self.pixel_list)
+
 
 class MetadataSuite:
     """Suite that generates catalog files and benchmarks the operations on them."""

src/hipscat/io/paths.py

@@ -3,8 +3,9 @@
 from __future__ import annotations
 
 import re
+from typing import Dict, List
 
-from hipscat.io.file_io.file_pointer import FilePointer, append_paths_to_pointer
+from hipscat.io.file_io.file_pointer import FilePointer, append_paths_to_pointer, get_fs
 from hipscat.pixel_math.healpix_pixel import INVALID_PIXEL, HealpixPixel
 
 ORDER_DIRECTORY_PREFIX = "Norder"
@@ -85,6 +86,42 @@ def get_healpix_from_path(path: str) -> HealpixPixel:
     return HealpixPixel(int(order), int(pixel))
 
 
+def pixel_catalog_files(
+    catalog_base_dir: FilePointer, pixels: List[HealpixPixel], storage_options: Dict | None = None
+) -> List[FilePointer]:
+    """Create a list of path *pointers* for pixel catalog files. This will not create the directory
+    or files.
+
+    The catalog file names will take the HiPS standard form of::
+
+        <catalog_base_dir>/Norder=<pixel_order>/Dir=<directory number>/Npix=<pixel_number>.parquet
+
+    Where the directory number is calculated using integer division as::
+
+        (pixel_number/10000)*10000
+
+    Args:
+        catalog_base_dir (FilePointer): base directory of the catalog (includes catalog name)
+        pixels (List[HealpixPixel]): the healpix pixels to create pointers to
+        storage_options (dict): the storage options for the file system to target when generating the paths
+    Returns (List[FilePointer]):
+        A list of paths to the pixels, in the same order as the input pixel list.
+    """
+    fs, _ = get_fs(catalog_base_dir, storage_options)
+    base_path_stripped = catalog_base_dir.removesuffix(fs.sep)
+    return [
+        fs.sep.join(
+            [
+                base_path_stripped,
+                f"{ORDER_DIRECTORY_PREFIX}={pixel.order}",
+                f"{DIR_DIRECTORY_PREFIX}={pixel.dir}",
+                f"{PIXEL_DIRECTORY_PREFIX}={pixel.pixel}.parquet",
+            ]
+        )
+        for pixel in pixels
+    ]
+
+
 def pixel_catalog_file(catalog_base_dir: FilePointer, pixel_order: int, pixel_number: int) -> FilePointer:
     """Create path *pointer* for a pixel catalog file. This will not create the directory
     or file.

tests/hipscat/io/test_paths.py

@@ -48,6 +48,12 @@ def test_pixel_catalog_file_nonint():
         paths.pixel_catalog_file("/foo", "zero", "five")
 
 
+def test_pixel_catalog_files():
+    expected = ["/foo/Norder=0/Dir=0/Npix=5.parquet", "/foo/Norder=1/Dir=0/Npix=16.parquet"]
+    result = paths.pixel_catalog_files("/foo", [HealpixPixel(0, 5), HealpixPixel(1, 16)])
+    assert expected == result
+
+
 def test_get_healpix_from_path():
     expected = HealpixPixel(5, 34)