[wip] add STAC items self-validation procedure

STACpopulator/models.py

@@ -1,4 +1,4 @@
-import datetime
+from datetime import datetime as datetime_type
 from typing import List, Literal, Optional
 
 from pydantic import BaseModel, Field
@@ -36,9 +36,9 @@ class STACItemProperties(BaseModel):
     In concrete implementations, users would want to define a new data model that inherits from this base model
     and extends it with properties tailored to the data they are ingesting.
     """
-    start_datetime: Optional[datetime.datetime] = None
-    end_datetime: Optional[datetime.datetime] = None
-    datetime_: Optional[datetime.datetime] = Field(None, alias="datetime")
+    start_datetime: Optional[datetime_type] = None
+    end_datetime: Optional[datetime_type] = None
+    datetime: Optional[datetime_type] = None
 
     def __setitem__(self, key, value):
         setattr(self, key, value)
@@ -48,3 +48,6 @@ def __getitem__(self, item):
 
     def __delitem__(self, item):
         return delattr(self, item)
+
+    def __contains__(self, item):
+        return hasattr(self, item)

STACpopulator/stac_utils.py

@@ -10,6 +10,7 @@
 import pystac
 import yaml
 from colorlog import ColoredFormatter
+from pystac.validation import validate as pystac_validate
 
 from STACpopulator.models import Geometry, STACItemProperties
 
@@ -181,21 +182,18 @@ def STAC_item_from_metadata(
     cfmeta = attrs["groups"]["CFMetadata"]["attributes"]
 
     # Create pydantic STAC item
+    props = item_props_data_model(**attrs["attributes"])
+    geom = item_geometry_model(**ncattrs_to_geometry(attrs))
     item = pystac.Item(
         id=iid,
-        geometry=item_geometry_model(**ncattrs_to_geometry(attrs)),
+        geometry=json.loads(geom.model_dump_json(by_alias=True)),
         bbox=ncattrs_to_bbox(attrs),
-        properties=item_props_data_model(
-            **attrs["attributes"],
-        ),
+        properties=json.loads(props.model_dump_json(by_alias=True)),
         datetime=None,
         start_datetime=dt_parser.parse(cfmeta["time_coverage_start"]),
         end_datetime=dt_parser.parse(cfmeta["time_coverage_end"]),
     )
 
-    # Convert pydantic STAC item to a PySTAC Item
-    item = pystac.Item(**json.loads(item.model_dump_json(by_alias=True)))
-
     root = attrs["access_urls"]
 
     for name, url in root.items():
@@ -205,7 +203,7 @@ def STAC_item_from_metadata(
         item.add_asset(name, asset)
 
     item.add_link(magpie_resource_link(root["HTTPServer"]))
-
+    item.validate()
     return item