[Archive] Fixes bug #110, returns None instead of crash when there is no file on server

Signed-off-by: Alexis Jeandet <alexis.jeandet@member.fsf.org>

Author: jeandet

speasy/core/direct_archive_downloader/direct_archive_downloader.py

@@ -20,16 +20,21 @@
 
 
 @CacheCall(cache_retention=timedelta(hours=24), is_pure=True)
-def _read_cdf(url: str, variable: str) -> SpeasyVariable:
+def _read_cdf(url: Optional[str], variable: str) -> Optional[SpeasyVariable]:
+    if url is None:
+        return None
     return load_variable(file=url, variable=variable)
 
 
-def _build_url(url_pattern: str, date: datetime, use_file_list=False) -> str:
+def _build_url(url_pattern: str, date: datetime, use_file_list=False) -> Optional[str]:
     base_ulr = url_pattern.format(Y=date.year, M=date.month, D=date.day)
     if not use_file_list:
         return base_ulr
     folder_url, rx = base_ulr.rsplit('/', 1)
-    return '/'.join((folder_url, sorted(list_files(folder_url, re.compile(rx)))[-1]))
+    files = sorted(list_files(folder_url, re.compile(rx)))
+    if len(files):
+        return '/'.join((folder_url, files[-1]))
+    return None
 
 
 def spilt_range(split_frequency: str, start_time: AnyDateTimeType, stop_time: AnyDateTimeType):

tests/test_direct_archive_downloader.py

@@ -97,9 +97,36 @@ def test_get_data(self, product, start, stop):
         v = spz.get_data(product, start, stop)
         self.assertIsNotNone(v)
 
-    def test_get_data_with_no_file(self):
-        v = spz.get_data(spz.inventories.tree.archive.cdpp.THEMIS.THA.L2.tha_scm.tha_scf_gse, "2018-03-10",
-                         "2018-03-11")
+    @data(
+        ("archive/cdpp/THEMIS/THA/L2/tha_scm/tha_scf_gse",
+         "2018-03-10",
+         "2018-03-11"),
+        ("archive/cda/MMS/MMS1/FGM/SRVY/mms1_fgm_srvy_l2/mms1_fgm_b_bcs_srvy_l2",
+         "2019-08-19",
+         "2019-08-25"),
+    )
+    @unpack
+    def test_get_data_with_no_file(self, product, start, stop):
+        v = spz.get_data(product, start, stop)
+        self.assertIsNone(v)
+
+    @data(
+        ("archive/cda/MMS/MMS1/FGM/SRVY/mms1_fgm_srvy_l2/mms1_fgm_b_bcs_srvy_l2",
+         "2010-08-19",
+         "2010-08-25"),
+        ("archive/cdpp/THEMIS/THA/L2/tha_scm/tha_scf_gse",
+         "2030-03-10",
+         "2030-03-11"),
+        ("archive/cda/MMS/MMS1/FPI/BURST/MOMS/mms1_fpi_brst_l2_des_moms/mms1_des_temppara_brst",
+         "2006-02-28",
+         "2006-03-02"),
+        ("archive/cda/MMS/MMS1/FPI/FAST/MOMS/mms1_fpi_fast_l2_des_moms/mms1_des_energyspectr_omni_fast",
+         "2010-01-30T10",
+         "2010-02-01T12"),
+    )
+    @unpack
+    def test_get_data_outside_of_range(self, product, start, stop):
+        v = spz.get_data(product, start, stop)
         self.assertIsNone(v)
 
     def test_axes_merging_across_files(self):