handle multiple MCF spatial extents as GeoJSON MultiPolygon geometries

Author: tomkralidis

pygeometa/schemas/ogcapi_records/__init__.py

@@ -18,7 +18,7 @@
 # those files. Users are asked to read the 3rd Party Licenses
 # referenced with those assets.
 #
-# Copyright (c) 2025 Tom Kralidis
+# Copyright (c) 2026 Tom Kralidis
 #
 # Permission is hereby granted, free of charge, to any person
 # obtaining a copy of this software and associated documentation
@@ -51,6 +51,7 @@
 from pygeometa.core import get_charstring
 from pygeometa.helpers import generate_datetime, json_dumps
 from pygeometa.schemas.base import BaseOutputSchema
+from pygeometa.schemas.util import generate_geometry
 
 THISDIR = os.path.dirname(os.path.realpath(__file__))
 
@@ -86,21 +87,8 @@ def write(self, mcf: dict, stringify: str = True) -> Union[dict, str]:
         self.lang1 = mcf['metadata'].get('language')
         self.lang2 = mcf['metadata'].get('language_alternate')
 
-        try:
-            minx, miny, maxx, maxy = (mcf['identification']['extents']
-                                      ['spatial'][0]['bbox'])
-            geometry = {
-                'type': 'Polygon',
-                'coordinates': [[
-                    [minx, miny],
-                    [minx, maxy],
-                    [maxx, maxy],
-                    [maxx, miny],
-                    [minx, miny]
-                ]]
-            }
-        except TypeError:
-            geometry = None
+        geometry = generate_geometry(
+            mcf['identification']['extents']['spatial'])
 
         title = get_charstring(mcf['identification'].get('title'),
                                self.lang1, self.lang2)

pygeometa/schemas/stac/__init__.py

@@ -18,7 +18,7 @@
 # those files. Users are asked to read the 3rd Party Licenses
 # referenced with those assets.
 #
-# Copyright (c) 2024 Tom Kralidis
+# Copyright (c) 2026 Tom Kralidis
 #
 # Permission is hereby granted, free of charge, to any person
 # obtaining a copy of this software and associated documentation
@@ -49,6 +49,7 @@
 from pygeometa.core import get_charstring
 from pygeometa.helpers import json_dumps
 from pygeometa.schemas.base import BaseOutputSchema
+from pygeometa.schemas.util import generate_geometry
 
 THISDIR = os.path.dirname(os.path.realpath(__file__))
 
@@ -81,8 +82,10 @@ def write(self, mcf: dict, stringify: str = True) -> Union[dict, str]:
         lang1 = mcf['metadata'].get('language')
         lang2 = mcf['metadata'].get('language_alternate')
 
-        minx, miny, maxx, maxy = (mcf['identification']['extents']
-                                  ['spatial'][0]['bbox'])
+        geometry = generate_geometry(
+            mcf['identification']['extents']['spatial'])
+
+        bbox = mcf['identification']['extents']['spatial'][0]['bbox']
 
         title = get_charstring(mcf['identification'].get('title'),
                                lang1, lang2)
@@ -93,17 +96,8 @@ def write(self, mcf: dict, stringify: str = True) -> Union[dict, str]:
             'stac-version': '1.0.0-beta.2',
             'id': mcf['metadata']['identifier'],
             'type': 'Feature',
-            'bbox': [minx, miny, maxx, maxy],
-            'geometry': {
-                'type': 'Polygon',
-                'coordinates': [[
-                    [minx, miny],
-                    [minx, maxy],
-                    [maxx, maxy],
-                    [maxx, miny],
-                    [minx, miny]
-                ]]
-            },
+            'bbox': bbox,
+            'geometry': geometry,
             'properties': {
                 'title': title[0],
                 'description': description[0],

pygeometa/schemas/util.py

@@ -0,0 +1,103 @@
+# =================================================================
+#
+# Terms and Conditions of Use
+#
+# Unless otherwise noted, computer program source code of this
+# distribution # is covered under Crown Copyright, Government of
+# Canada, and is distributed under the MIT License.
+#
+# The Canada wordmark and related graphics associated with this
+# distribution are protected under trademark law and copyright law.
+# No permission is granted to use them outside the parameters of
+# the Government of Canada's corporate identity program. For
+# more information, see
+# http://www.tbs-sct.gc.ca/fip-pcim/index-eng.asp
+#
+# Copyright title to all 3rd party software distributed with this
+# software is held by the respective copyright holders as noted in
+# those files. Users are asked to read the 3rd Party Licenses
+# referenced with those assets.
+#
+# Copyright (c) 2026 Tom Kralidis
+#
+# Permission is hereby granted, free of charge, to any person
+# obtaining a copy of this software and associated documentation
+# files (the "Software"), to deal in the Software without
+# restriction, including without limitation the rights to use,
+# copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the
+# Software is furnished to do so, subject to the following
+# conditions:
+#
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+# OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+# HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+# OTHER DEALINGS IN THE SOFTWARE.
+#
+# =================================================================
+
+import logging
+
+LOGGER = logging.getLogger(__name__)
+
+
+def generate_geometry(spatial: list) -> dict:
+    """
+    Helper function to generate GeoJSON geometry from an
+    MCF spatial extent
+
+    :param spatial: `list` of spatial extents defined
+
+    :returns: `dict` of GeoJSON geometry
+    """
+
+    geometry = None
+
+    if len(spatial) == 1:
+        LOGGER.debug('spatial extent is a default bbox')
+        try:
+            minx, miny, maxx, maxy = (spatial[0]['bbox'])
+            geometry = {
+                'type': 'Polygon',
+                'coordinates': [[
+                    [minx, miny],
+                    [minx, maxy],
+                    [maxx, maxy],
+                    [maxx, miny],
+                    [minx, miny]
+                ]]
+            }
+        except TypeError:
+            geometry = None
+    elif len(spatial) > 1:
+        LOGGER.debug('spatial extent is a multiple bbox')
+        bboxes = []
+        for s in spatial:
+            try:
+                minx, miny, maxx, maxy = (s['bbox'])
+                bboxes.append([[
+                        [minx, miny],
+                        [minx, maxy],
+                        [maxx, maxy],
+                        [maxx, miny],
+                        [minx, miny]
+                    ]])
+            except TypeError:
+                LOGGER.debug('bbox failed')
+
+        geometry = {
+            'type': 'MultiPolygon',
+            'coordinates': bboxes
+        }
+    else:
+        LOGGER.debug('Invalid spatial extent')
+        geometry = None
+
+    return geometry