Added suggestions and a couple other things for Pylint

tests/unit/test_cmr_search.py

@@ -1,5 +1,6 @@
 from shutil import rmtree
 from tempfile import mkdtemp
+from os.path import exists
 from unittest import TestCase
 from unittest.mock import patch, Mock
 
@@ -9,8 +10,11 @@
 
 from varinfo.cmr_search import (get_granules, get_granule_link,
                                 download_granule)
-from varinfo.exceptions import (CMRQueryException, MissingGranuleDownloadLinks,
-                                MissingPositionalArguments, GranuleDownloadException)
+from varinfo.exceptions import (CMRQueryException,
+                                MissingGranuleDownloadLinks,
+                                MissingPositionalArguments,
+                                GranuleDownloadException,
+                                DirectoryCreationException)
 
 
 class TestQuery(TestCase):
@@ -21,7 +25,8 @@ def setUp(self):
         self.output_dir = mkdtemp()
 
     def tearDown(self):
-        rmtree(self.output_dir)
+        if exists(self.output_dir):
+            rmtree(self.output_dir)
 
     @patch('varinfo.cmr_search.GranuleQuery', spec=GranuleQuery)
     def test_with_concept_id(self, granule_query_mock):
@@ -260,25 +265,12 @@ def test_exceptions_granule_link(self):
 
     def test_download_gran_exceptions(self):
         ''' Check if exceptions are raised for incorrect input parameters
-        '''
-
-        with self.assertRaises(MissingPositionalArguments):
-            # Input parameter, token, is missing
-            download_granule(granule_link='https://foo.gov/example.nc4')
-
-        with self.assertRaises(NotADirectoryError):
-            # Input parameter, `out_directory` should be a real directory
-            download_granule('https://foo.gov/example.nc4', 
-                             '/Usr/foo/dir',
-                             'foo')
-
-        with self.assertRaises(MissingPositionalArguments):
-            # Missing argument, `granule_link`
-            download_granule(token='foo')
-
-        with self.assertRaises(ValueError):
-            # `granule_link` should be str or bytes like not int
-            download_granule(granule_link=0, token='foo')
+        ''' 
+        with self.assertRaises(DirectoryCreationException):
+            # Input parameter, `out_directory` is a path that does not exist
+            download_granule(granule_link='https://foo.gov/example.nc4',
+                             token='foo',
+                             out_directory='/Usr/foo/dir')
 
         with self.assertRaises(GranuleDownloadException):
             # Not a real https link
@@ -308,12 +300,14 @@ def test_download_granule(self, mock_requests_get):
         mock_response = self._mock_requests(content=mock_content)
         # Set the return_value of `mock_requests_get` to mock_response
         mock_requests_get.return_value = mock_response
-        file_path = download_granule(link, self.output_dir, token='foo')
+        file_path = download_granule(link,
+                                     token="foo",
+                                     out_directory=self.output_dir)
         # Check if `download_granule` was called once with expected parameters
-        mock_requests_get.assert_called_once_with(link, headers=
-                                                  {'Authorization':
-                                                      f'Bearer {"foo"}'},
-                                                  timeout=10)
+        mock_requests_get.assert_called_once_with(
+            link,
+            headers={'Authorization': 'Bearer foo'},
+            timeout=10)
         # Check if download file contains expected content from `requests.get`
         with self.subTest('Test if the downloaded file contains '
                           'expected content'):

varinfo/cmr_search.py

@@ -8,8 +8,11 @@
 from cmr import GranuleQuery, CMR_OPS
 import requests
 
-from varinfo.exceptions import (CMRQueryException, MissingGranuleDownloadLinks,
-                                MissingPositionalArguments, GranuleDownloadException)
+from varinfo.exceptions import (CMRQueryException,
+                                MissingGranuleDownloadLinks,
+                                MissingPositionalArguments,
+                                GranuleDownloadException,
+                                DirectoryCreationException)
 
 
 def get_granules(concept_id: str = None,
@@ -60,7 +63,7 @@ def get_granules(concept_id: str = None,
 
     except Exception as cmr_exception:
         # Use custom exception, CMRQueryException, if CMR fails
-        raise CMRQueryException(str(cmr_exception))
+        raise CMRQueryException(str(cmr_exception)) from cmr_exception
 
     # Check if granule_response is an empty list
     if len(granule_response) == 0:
@@ -81,38 +84,32 @@ def get_granule_link(granule_response: list) -> str:
     return granule_link
 
 
-def download_granule(granule_link: str = None,
-                     out_directory: str = os.getcwd(),
-                     token: str = None) -> str:
+def download_granule(granule_link: str,
+                     token: str,
+                     out_directory: str = os.getcwd()) -> str:
     ''' Use the requests module to download data via https.
         * granule_link: granule download URL.
+        * token: Earthdata Login (EDL) bearer_token
         * out_directory: path to save downloaded granule
             (the default is the current directory).
-        * token: Earthdata Login (EDL) bearer_token
     '''
-    if granule_link is not None:  # Check if input parameter was entered
-        if isinstance(granule_link, str):  # Check if granule link is a string
-            # Check if `out_directory` is a directory and create out_filename
-            if os.path.isdir(out_directory):
-                out_filename = out_directory + '/' + os.path.basename(granule_link)
-            else:
-                raise NotADirectoryError('Input directory '
-                                         '"out_directory" is not a directory')
-        else:
-            raise ValueError('Not a string')
-    else:
-        raise MissingPositionalArguments('granule_link')
+    # Create `out_directory` if it does not exist and create out_filename
+    if not os.path.isdir(out_directory):
+        try:
+            os.mkdir(out_directory)
+        except Exception as os_exception:
+            raise DirectoryCreationException(
+                str(os_exception)) from os_exception
+    out_filename = os.path.join(out_directory, os.path.basename(granule_link))
 
-    if token is not None:
-        try:  # Write content of data to out_filename and return response
-            response = requests.get(granule_link,
-                                    headers={'Authorization': f'Bearer {token}'},
-                                    timeout=10)
-            with open(out_filename, 'wb') as file_download:
-                file_download.write(response.content)
-            return out_filename
-        except Exception as requests_exception:
-            # Custom exception for error from `requests.get`
-            raise GranuleDownloadException(str(requests_exception))
-    else:
-        raise MissingPositionalArguments('token')
+    try:  # Write content of data to out_filename and return response
+        response = requests.get(granule_link,
+                                headers={'Authorization': f'Bearer {token}'},
+                                timeout=10)
+        with open(out_filename, 'wb') as file_download:
+            file_download.write(response.content)
+        return out_filename
+    except Exception as requests_exception:
+        # Custom exception for error from `requests.get`
+        raise GranuleDownloadException(
+            str(requests_exception)) from requests_exception

varinfo/exceptions.py

@@ -95,10 +95,20 @@ def __init__(self, download_link):
 
 
 class GranuleDownloadException(CustomError):
-    ''' This exception is raised when a query to CMR fails.
+    ''' This exception is raised when the requests modules fails.
     '''
 
     def __init__(self, granule_download_exception_message):
         super().__init__('GranuleDownloadException',
                          'requests module failed with the following error: '
                          f'{granule_download_exception_message}')
+
+
+class DirectoryCreationException(CustomError):
+    ''' This exception is raised when creating a directory fails.
+    '''
+
+    def __init__(self, directory_creation_exception_message):
+        super().__init__('DirectoryCreationException',
+                         'directory creation failed with the following error: '
+                         f'{directory_creation_exception_message}')