Add basic checks for errors.

Author: DinoBektesevic

astroquery/ipac/irsa/most.py

@@ -1,6 +1,7 @@
 import io
 import re
 import tarfile
+import warnings
 
 from bs4 import BeautifulSoup
 
@@ -9,7 +10,7 @@
 
 from astroquery.query import BaseQuery
 from astroquery.utils import class_or_instance
-from astroquery.exceptions import InvalidQueryError
+from astroquery.exceptions import InvalidQueryError, NoResultsWarning
 
 from . import conf
 
@@ -354,6 +355,11 @@ def get_images(self, catalog="wise_merge", input_mode="name_input", ephem_step=0
             with_tarballs=True,
         )
 
+        if queryres is None:
+            # A warning will already be issued by query_object so no need to
+            # raise a new one here.
+            return None
+
         response = self._request("GET", queryres["fits_tarball"],
                                  save=save, savedir=savedir)
 
@@ -524,10 +530,28 @@ def query_object(self, catalog="wise_merge", input_mode="name_input", output_mod
         response = self._request("POST", self.URL,
                                  data=qparams, timeout=self.TIMEOUT)
 
+        # service unreachable or some other reason
+        if not response.ok:
+            raise response.raise_for_status()
+
+        # MOST will not raise an bad response if the query is bad because they
+        # are not a REST API
+        if "MOST: *** error:" in response.text:
+            raise InvalidQueryError(response.text)
+
+        # presume that response is HTML to simplify conditions
+        if "Number of Matched Image Frames   = 0" in response.text:
+            warnings.warn("Number of Matched Image Frames   = 0", NoResultsWarning)
+            return None
+
         if qparams["output_mode"] in ("Brief", "Gator"):
             return Table.read(response.text, format="ipac")
         elif qparams["output_mode"] == "VOTable":
-            return votable.parse(io.BytesIO(response.content))
+            matches = votable.parse(io.BytesIO(response.content))
+            if matches.get_table_by_index(0).nrows == 0:
+                warnings.warn("Number of Matched Image Frames   = 0", NoResultsWarning)
+                return None
+            return matches
         else:
             return self._parse_full_regular_response(response, qparams["fits_region_files"])
 

astroquery/ipac/irsa/tests/test_most.py

@@ -44,6 +44,21 @@
 }
 
 
+class MockResponse(MockResponse):
+    """
+    We overwrite the default MockResponse to provide it wih `ok`
+    attribute. In these tests it is assumed they are all expected
+    to pass so it's fine to put it always True.
+
+    This is ok, these tests can really only cover parsing errors
+    because the mocking of failure cases of MOST is too complicated.
+    These tests are farmed out to remote data tests.
+    """
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.ok = True
+
+
 def data_path(filename):
     """Returns the path to the file in the module's test data directory."""
     data_dir = os.path.join(os.path.dirname(__file__), 'data')

astroquery/ipac/irsa/tests/test_most_remote.py

@@ -1,15 +1,14 @@
 # Licensed under a 3-clause BSD style license - see LICENSE.rst
-
-import io
 import os
 import pytest
+import warnings
 
 import numpy as np
 
 import astropy.io.fits as fits
 from astropy.table import Table
 from astroquery.ipac.irsa import Most
-
+from astroquery.exceptions import InvalidQueryError
 
 # each MOST query is given a PID and a temporary directory availible publicly
 # from this base URL. This URL is then used to create links on the returned
@@ -46,8 +45,6 @@ def test_query_object():
     # not returned in same order nor header width. So we have to compare
     # manually
     results = Table.read(data_path("most_regular_results.tbl"), format="ipac")
-    metadata = Table.read(data_path("most_imgframes_matched_final_table.tbl"), format="ipac")
-    url = REGULAR_BASE_URL + "ds9region/ds9_orbit_path.reg"
 
     columns = [col for col in results.columns if col not in ("image_url", "postcard_url", "region_file")]
     for col in columns:
@@ -89,7 +86,44 @@ def test_list_catalogs():
     ]
 
     cats = Most.list_catalogs()
-
     assert expected == cats
 
 
+@pytest.mark.remote_data
+def test_no_results():
+    with warnings.catch_warnings():
+        warnings.simplefilter("ignore")
+        response = Most.query_object(
+            obj_name="Victoria",
+            obs_begin="2019-05-21",
+            obs_end="2019-05-22"
+        )
+
+    assert response is None
+
+    with warnings.catch_warnings():
+        warnings.simplefilter("ignore")
+        response = Most.get_images(
+            obj_name="Victoria",
+            obs_begin="2019-05-21",
+            obs_end="2019-05-22"
+        )
+
+    assert response is None
+
+
+@pytest.mark.remote_data
+def test_invalid_query():
+    with pytest.raises(InvalidQueryError):
+        Most.query_object(
+            obj_name="Victoria",
+            obs_begin="2014-05-21",
+            obs_end="2014-05-19"
+        )
+
+    with pytest.raises(InvalidQueryError):
+        Most.get_images(
+            obj_name="Victoria",
+            obs_begin="2014-05-21",
+            obs_end="2014-05-19"
+        )