feat: permissive extent deserialization (#1559)

* feat: permissive extent deserialization

* chore: update changelog

* Update tests/test_collection.py

Co-authored-by: Julia Signell <jsignell@gmail.com>

* fix: tests

---------

Co-authored-by: Julia Signell <jsignell@gmail.com>

Author: gadomski

CHANGELOG.md

@@ -8,6 +8,10 @@
   media type value for these types and new media types COPC and VND_PMTILES
   ([#1554](https://github.com/stac-utils/pystac/pull/1554))
 
+### Fixed
+
+- More permissive collection extent deserialization ([#1559](https://github.com/stac-utils/pystac/pull/1559))
+
 ## [v1.13.0] - 2025-04-15
 
 ### Added

pystac/collection.py

@@ -1,7 +1,7 @@
 from __future__ import annotations
 
 import warnings
-from collections.abc import Iterable
+from collections.abc import Iterable, Sequence
 from copy import deepcopy
 from datetime import datetime, timezone
 from typing import (
@@ -71,7 +71,7 @@ class SpatialExtent:
 
     def __init__(
         self,
-        bboxes: Bboxes | list[float | int],
+        bboxes: Bboxes | Sequence[float | int],
         extra_fields: dict[str, Any] | None = None,
     ) -> None:
         if not isinstance(bboxes, list):
@@ -199,7 +199,7 @@ class TemporalExtent:
 
     def __init__(
         self,
-        intervals: TemporalIntervals | list[datetime | None],
+        intervals: TemporalIntervals | Sequence[datetime | None],
         extra_fields: dict[str, Any] | None = None,
     ):
         if not isinstance(intervals, list):
@@ -652,7 +652,17 @@ def from_dict(
         id = d.pop("id")
         description = d.pop("description")
         license = d.pop("license")
-        extent = Extent.from_dict(d.pop("extent"))
+        if extent_dict := d.pop("extent", None):
+            extent = Extent.from_dict(extent_dict)
+        else:
+            warnings.warn(
+                "Collection is missing extent, setting default spatial and "
+                "temporal extents"
+            )
+            extent = Extent(
+                spatial=SpatialExtent([-90, -180, 90, 180]),
+                temporal=TemporalExtent([None, None]),
+            )
         title = d.pop("title", None)
         stac_extensions = d.pop("stac_extensions", None)
         keywords = d.pop("keywords", None)

tests/test_collection.py

@@ -400,7 +400,7 @@ def test_temporal_extent_allows_single_interval() -> None:
     end_datetime = str_to_datetime("2022-01-31T23:59:59Z")
 
     interval = [start_datetime, end_datetime]
-    temporal_extent = TemporalExtent(intervals=interval)  # type: ignore
+    temporal_extent = TemporalExtent(intervals=interval)
 
     assert temporal_extent.intervals == [interval]
 
@@ -820,3 +820,25 @@ def test_from_items_with_providers(sample_item_collection: ItemCollection) -> No
 
     provider = collection.providers[0]
     assert provider and provider.name == "pystac"
+
+
+def test_from_dict_null_extent(collection: Collection) -> None:
+    # https://github.com/stac-utils/pystac/issues/1558
+    # https://github.com/EOPF-Sample-Service/eopf-stac/issues/18
+    d = collection.to_dict()
+    d["extent"] = None
+    with pytest.warns(UserWarning):
+        c = Collection.from_dict(d)
+
+    assert c.extent.spatial.to_dict()["bbox"] == [[-90, -180, 90, 180]]
+    assert c.extent.temporal.to_dict()["interval"] == [[None, None]]
+
+
+def test_from_dict_missing_extent(collection: Collection) -> None:
+    d = collection.to_dict()
+    del d["extent"]
+    with pytest.warns(UserWarning):
+        c = Collection.from_dict(d)
+
+    assert c.extent.spatial.to_dict()["bbox"] == [[-90, -180, 90, 180]]
+    assert c.extent.temporal.to_dict()["interval"] == [[None, None]]