add datetime validation for collection time intervals

CHANGELOG.md

@@ -1,6 +1,8 @@
 
 ## Unreleased
 
+- Add datetime validation for collection's time intervals (Must follow [`RFC 3339, section 5.6.`](https://datatracker.ietf.org/doc/html/rfc3339#section-5.6))
+
 ## 3.2.0 (2025-03-20)
 
 - Move `validate_bbox` and `validate_datetime` field validation functions outside the Search class (to enable re-utilization)

CONTRIBUTING.md

@@ -0,0 +1,26 @@
+# Contributing
+
+Issues and pull requests are more than welcome.
+
+**dev install**
+
+```bash
+git clone https://github.com/stac-utils/stac-pydantic.git
+cd stac-pydantic
+python -m pip install -e ".[dev]"
+```
+
+You can then run the tests with the following command:
+
+```sh
+python -m pytest --cov stac_pydantic --cov-report term-missing
+```
+
+
+**pre-commit**
+
+This repo is set to use `pre-commit` to run *ruff*, *pydocstring* and mypy when committing new code.
+
+```bash
+pre-commit install
+```

stac_pydantic/collection.py

@@ -3,7 +3,7 @@
 from pydantic import Field
 
 from stac_pydantic.catalog import _Catalog
-from stac_pydantic.shared import Asset, NumType, Provider, StacBaseModel
+from stac_pydantic.shared import Asset, NumType, Provider, StacBaseModel, UtcDatetime
 
 
 class SpatialExtent(StacBaseModel):
@@ -19,7 +19,7 @@ class TimeInterval(StacBaseModel):
     https://github.com/radiantearth/stac-spec/blob/v1.0.0/collection-spec/collection-spec.md#temporal-extent-object
     """
 
-    interval: List[List[Union[str, None]]]
+    interval: List[List[Union[UtcDatetime, None]]]
 
 
 class Extent(StacBaseModel):

tests/api/examples/v1.0.0/example-collection-list.json

@@ -63,8 +63,8 @@
              "temporal":{
                 "interval":[
                    [
-                      "2000-03-04T12:00:00.000000Z",
-                      "2006-12-31T12:00:00.000000Z"
+                      "2000-03-04T12:00:00Z",
+                      "2006-12-31T12:00:00Z"
                    ]
                 ]
              }

tests/api/test_collections.py

@@ -9,5 +9,5 @@
 
 def test_collection_list():
     test_collection_list = request(EXAMPLE_COLLECTION_LIST, PATH)
-    valid_collection_list = Collections(**test_collection_list).model_dump()
+    valid_collection_list = Collections(**test_collection_list).model_dump(mode="json")
     dict_match(test_collection_list, valid_collection_list)

tests/conftest.py

@@ -48,7 +48,7 @@ def dict_match(d1: dict, d2: dict):
         # to compare the values as datetime objects.
         elif "datetime" in diff[1]:
             dates = [
-                UtcDatetimeAdapter.validate_strings(date)
+                UtcDatetimeAdapter.validate_strings(date, strict=True)
                 if isinstance(date, str)
                 else date
                 for date in diff[2]

tests/test_models.py

@@ -6,6 +6,7 @@
 from shapely.geometry import shape
 
 from stac_pydantic import Collection, Item, ItemProperties
+from stac_pydantic.collection import TimeInterval
 from stac_pydantic.extensions import _fetch_and_cache_schema, validate_extensions
 from stac_pydantic.links import Link, Links
 from stac_pydantic.shared import MimeTypes, StacCommonMetadata
@@ -81,13 +82,13 @@ def test_version_extension_item() -> None:
 
 def test_version_extension_collection() -> None:
     test_coll = request(VERSION_EXTENSION_COLLECTION)
-    valid_coll = Collection(**test_coll).model_dump()
+    valid_coll = Collection(**test_coll).model_dump(mode="json")
     dict_match(test_coll, valid_coll)
 
 
 def test_item_assets_extension() -> None:
     test_coll = request(ITEM_ASSET_EXTENSION)
-    valid_coll = Collection(**test_coll).model_dump()
+    valid_coll = Collection(**test_coll).model_dump(mode="json")
     dict_match(test_coll, valid_coll)
 
 
@@ -139,7 +140,9 @@ def test_extension_validation_schema_cache() -> None:
 def test_to_json(infile, model):
     test_item = request(infile)
     validated = model(**test_item)
-    dict_match(json.loads(validated.model_dump_json()), validated.model_dump())
+    dict_match(
+        json.loads(validated.model_dump_json()), validated.model_dump(mode="json")
+    )
 
 
 def test_item_to_json() -> None:
@@ -345,3 +348,34 @@ def test_item_bbox_validation() -> None:
     test_item["bbox"] = None
     with pytest.raises(ValueError, match="bbox is required if geometry is not null"):
         Item(**test_item)
+
+
+@pytest.mark.parametrize(
+    "interval",
+    [
+        [[None, "yo"]],
+        [["yo", None]],
+        [["yo", "yo"]],
+    ],
+)
+def test_time_intervals_invalid(interval) -> None:
+    """Check Time Interval model."""
+    with pytest.raises(ValidationError):
+        TimeInterval(interval=interval)
+
+
+@pytest.mark.parametrize(
+    "interval",
+    [
+        [["2024-01-01T00:00:00Z", None]],
+        [[None, "2024-01-01T00:00:00Z"]],
+        [["2023-01-01T00:00:00Z", "2024-01-01T00:00:00Z"]],
+        [
+            ["2023-01-01T00:00:00Z", "2024-01-01T00:00:00Z"],
+            ["2023-01-31T00:00:00Z", "2024-01-01T00:00:00Z"],
+        ],
+    ],
+)
+def test_time_intervals_valid(interval) -> None:
+    """Check Time Interval model."""
+    assert TimeInterval(interval=interval)