Merge pull request #15 from rsignell-usgs/auth

use requests before read_csv to get auth

Author: ocefpaf

erddapy/erddapy.py

@@ -1,5 +1,7 @@
 from __future__ import (absolute_import, division, print_function)
 
+import requests
+
 try:
     from urllib.parse import quote_plus
 except ImportError:
@@ -273,16 +275,20 @@ def get_var_by_attr(self, dataset_id, **kwargs):
             ['latitude', 'longitude', 'time', 'depth']
 
         """
+        from io import StringIO
+
         try:
             import pandas as pd
+
         except ImportError:
             raise ImportError('pandas is needed to use `get_var_by_attr`.')
         info_url = self.get_info_url(dataset_id, response='csv')
 
         # Creates the variables dictionary for the `get_var_by_attr` lookup.
         if not self._variables or self._dataset_id != dataset_id:
             variables = {}
-            _df = pd.read_csv(info_url)
+            r = requests.get(info_url, verify=True)
+            _df = pd.read_csv(StringIO(r.text))
             self._dataset_id = dataset_id
             for variable in set(_df['Variable Name']):
                 attributes = _df.loc[