add sort direction

spaceweather_processing/app.py

@@ -136,7 +136,7 @@ class DataProductDB:
 
         # if a &sort=<field> url parameter is given then use sort, otherwise omit it (backward compatibility)
         if sort:
-            if sort[0]=='-':
+            if sort.startswith('-'):
                 direction = -1
                 sort = sort[1:]
             else: