Added function to normalise date strings

observatory_platform/date_utils.py

@@ -0,0 +1,34 @@
+# Copyright 2024 Curtin University
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Author: Keegan Smith
+
+from zoneinfo import ZoneInfo
+
+from dateutil import parser
+
+
+def normalise_datetime(dt_string: str) -> str:
+    """
+    Converts a date or datetime string to an isoformatted datetime string at +0000UTC
+
+    :param dt_string:  The string to convert
+    :return: The ISO formatted datetime string
+    """
+    dt = parser.parse(dt_string)  # Parse string to datetime object
+    if not dt.utcoffset():  # If no timezone present, assume +0000UTC
+        dt = dt.replace(tzinfo=ZoneInfo("UTC"))
+    dt = dt.astimezone(ZoneInfo("UTC"))
+
+    return dt.isoformat()

observatory_platform/tests/test_date_utils.py

@@ -0,0 +1,49 @@
+# Copyright 2024 Curtin University
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Author: Keegan Smith
+
+import unittest
+
+from observatory_platform.date_utils import normalise_datetime
+
+
+class test_normalise_datetime(unittest.TestCase):
+    """Tests for normalise_datetime"""
+
+    def test_good_inputs(self):
+        inputs = [
+            "2024-01-01 12:00:00+0000",
+            "2024-01-01 00:00:00+0800",
+            "2024-01-01 12:00:00-0800",
+            "2024-01-01 12:00:00Z",
+            "2024-01-01 12:00:00UTC+1",
+        ]
+        expected_outputs = [
+            "2024-01-01T12:00:00+00:00",
+            "2023-12-31T16:00:00+00:00",
+            "2024-01-01T20:00:00+00:00",
+            "2024-01-01T12:00:00+00:00",
+            "2024-01-01T13:00:00+00:00",
+        ]
+        for input, expected_output in zip(inputs, expected_outputs):
+            actual_output = normalise_datetime(input)
+            self.assertEqual(expected_output, actual_output)
+
+    def test_missing_tz(self):
+        inputs = ["2024-01-01 00:00:00", "2024-01-01T12:00:00"]
+        expected_outputs = ["2024-01-01T00:00:00+00:00", "2024-01-01T12:00:00+00:00"]
+        for input, expected_output in zip(inputs, expected_outputs):
+            actual_output = normalise_datetime(input)
+            self.assertEqual(expected_output, actual_output)

pyproject.toml

@@ -53,6 +53,7 @@ dependencies = [
     "validators<=0.20.0",
     "xmltodict",
     "tenacity",
+    "dateutils",
 ]
 
 [project.optional-dependencies]