Resolve "Lacking sanity checks to iricdata connection"

Closes #21 (closed)

pyiricdata/Client.py

@@ -269,6 +269,18 @@ class Client:
             annotation = annotation.json()
         return annotation
 
+
+    def get_file_content(self, file_id):
+        """Returns datafile content for a given file_id"""
+
+        conn = self.get_file_data_conn(file_id)
+
+        if conn is not None:
+            return conn.content
+        else:
+            return None
+
+
     """ Return a connector of the contents of a file for a given file_id """
     def get_file_data_conn(self, file_id):
         dwnl_url = os.path.join(self.url,
@@ -297,17 +309,22 @@ class Client:
     """
     def filter_datafiles(self, term, field='filename', exact_match=False, **kwargs):
         df = self.get_datafiles_list(**kwargs)
-
-        if exact_match:
-            return df[df[field].str.fullmatch(term)]
+        if df is None:
+            sys.stderr.write("Please try again with more arguments, for more details please see function get_datafiles_list()")
+            return None
+        elif df.empty:
+            return None
         else:
-            return df[df[field].str.contains(term)]
+            if exact_match:
+                return df[df[field].str.fullmatch(term)]
+            else:
+                return df[df[field].str.contains(term)]
 
     """ Get file content according to file_id """
     def get_file(self, file_id):
         try:
             file_metadata = self.get_file_metadata(file_id)
-            file_content = self.get_file_data_conn(file_id).content
+            file_content = self.get_file_content(file_id)
             file_annotation = self.get_file_annotation(file_id)
             return IDF(file_metadata, file_content, file_annotation)
         except TypeError:
@@ -326,6 +343,7 @@ class Client:
             filename = file_meta['filename'] if filename is None else filename
             out_file_path = os.path.join(folder_out, filename)
             file_conn = self.get_file_data_conn(file_id)
+            assert file_conn is not None  # should never be None here
             if os.path.exists(out_file_path):
                 sys.stderr.write('Warning: File already exists at ' +
                                  'location %s, skipping.\n' % out_file_path)