fix TypeError when offline

Simplenote.authenticate() and get_token() usually return a str.  When
offline, these methods return None.  The get_note(), update_note(), etc.
do not consider for this behavior.  Therefore, None will be set to http
header, and TypeError will occur when sending a request.

Related: cpbotha/nvpy#191

BROKEN CHANGE:

authenticate() and get_token() no longer catch the IOError,
BadStatusLine and part of HTTPError errors.

simplenote/simplenote.py

@@ -15,13 +15,13 @@
     from urllib.error import HTTPError
     import urllib.parse as urllib
     import html
-    from http.client import BadStatusLine
+    from http.client import HTTPException, BadStatusLine
 else:
     import urllib2
     from urllib2 import HTTPError
     import urllib
     from HTMLParser import HTMLParser
-    from httplib import BadStatusLine
+    from httplib import HTTPException, BadStatusLine
 
 import base64
 import time
@@ -71,7 +71,12 @@ def authenticate(self, user, password):
 
         Returns:
             Simplenote API token as string
-            
+
+        Raises:
+            - SimplenoteLoginFailed
+            - HTTPError
+            - HTTPException
+            - IOError
         """
 
         request = Request(AUTH_URL)
@@ -83,10 +88,10 @@ def authenticate(self, user, password):
         try:
             res = urllib2.urlopen(request).read()
             token = json.loads(res.decode('utf-8'))["access_token"]
-        except (HTTPError, BadStatusLine):
-            raise SimplenoteLoginFailed('Login to Simplenote API failed!')
-        except IOError: # no connection exception
-            token = None
+        except HTTPError as e:
+            if e.code == 401:
+                raise SimplenoteLoginFailed('Login to Simplenote API failed! Check email address and password.')
+            raise
         return token
 
     def get_token(self):
@@ -98,6 +103,10 @@ def get_token(self):
         Returns:
             Simplenote API token as string
 
+        Raises:
+            - HTTPError
+            - HTTPException
+            - IOError
         """
         if self.token == None:
             self.token = self.authenticate(self.username, self.password)
@@ -125,9 +134,13 @@ def get_note(self, noteid, version=None):
         if version is not None:
             params_version = '/v/' + str(version)
 
+        try:
+            token = self.get_token()
+        except Exception as e:
+            return e, -1
         params = '/i/%s%s' % (str(noteid), params_version)
         request = Request(DATA_URL+params)
-        request.add_header(self.header, self.get_token())
+        request.add_header(self.header, token)
         try:
             response = urllib2.urlopen(request)
         except HTTPError as e:
@@ -179,10 +192,14 @@ def update_note(self, note):
         else:
             url = '%s/i/%s?response=1' % (DATA_URL, noteid)
 
+        try:
+            token = self.get_token()
+        except Exception as e:
+            return e, -1
         # TODO: Could do with being consistent here. Everywhere else is Request(DATA_URL+params)
         note_to_update = self.__remove_simplenote_api_fields(note_to_update)
         request = Request(url, data=json.dumps(note_to_update).encode('utf-8'))
-        request.add_header(self.header, self.get_token())
+        request.add_header(self.header, token)
         request.add_header('Content-Type', 'application/json')
 
         response = ""
@@ -267,8 +284,12 @@ def get_note_list(self, data=True, since=None, tags=[]):
             params += '&data=true'
 
         # perform initial HTTP request
+        try:
+            token = self.get_token()
+        except Exception as e:
+            return e, -1
         request = Request(DATA_URL+params)
-        request.add_header(self.header, self.get_token())
+        request.add_header(self.header, token)
         try:
             response = urllib2.urlopen(request)
             response_notes = json.loads(response.read().decode('utf-8'))
@@ -295,7 +316,7 @@ def get_note_list(self, data=True, since=None, tags=[]):
 
             # perform the actual HTTP request
             request = Request(DATA_URL+params)
-            request.add_header(self.header, self.get_token())
+            request.add_header(self.header, token)
             try:
                 response = urllib2.urlopen(request)
                 response_notes = json.loads(response.read().decode('utf-8'))
@@ -368,9 +389,13 @@ def delete_note(self, note_id):
         if (status == -1):
             return note, status
 
+        try:
+            token = self.get_token()
+        except Exception as e:
+            return e, -1
         params = '/i/%s' % (str(note_id))
         request = Request(url=DATA_URL+params, method='DELETE')
-        request.add_header(self.header, self.get_token())
+        request.add_header(self.header, token)
         try:
             response = urllib2.urlopen(request)
         except (IOError, BadStatusLine) as e: