feat(exceptions): separate failed signin error

Closes #1472

This makes sign in failures their own class of exceptions, while still
inheriting from NotSignedInException to not break backwards
compatability for any existing client code. This should allow users
to get out more specific exceptions more easily on what failed with
their authentication request.

tableauserverclient/__init__.py

@@ -56,6 +56,7 @@
     PDFRequestOptions,
     RequestOptions,
     MissingRequiredFieldError,
+    FailedSignInError,
     NotSignedInError,
     ServerResponseError,
     Filter,
@@ -79,6 +80,7 @@
     "DatabaseItem",
     "DataFreshnessPolicyItem",
     "DatasourceItem",
+    "FailedSignInError",
     "FavoriteItem",
     "FlowItem",
     "FlowRunItem",

tableauserverclient/server/__init__.py

@@ -11,7 +11,7 @@
 from tableauserverclient.server.sort import Sort
 from tableauserverclient.server.server import Server
 from tableauserverclient.server.pager import Pager
-from tableauserverclient.server.endpoint.exceptions import NotSignedInError
+from tableauserverclient.server.endpoint.exceptions import FailedSignInError, NotSignedInError
 
 from tableauserverclient.server.endpoint import (
     Auth,
@@ -57,6 +57,7 @@
     "Sort",
     "Server",
     "Pager",
+    "FailedSignInError",
     "NotSignedInError",
     "Auth",
     "CustomViews",

tableauserverclient/server/endpoint/endpoint.py

@@ -19,6 +19,7 @@
 from tableauserverclient.server.request_options import RequestOptions
 
 from tableauserverclient.server.endpoint.exceptions import (
+    FailedSignInError,
     ServerResponseError,
     InternalServerError,
     NonXMLResponseError,
@@ -160,7 +161,7 @@ def _check_status(self, server_response: "Response", url: Optional[str] = None):
             try:
                 if server_response.status_code == 401:
                     # TODO: catch this in server.py and attempt to sign in again, in case it's a session expiry
-                    raise NotSignedInError(server_response.content, url)
+                    raise FailedSignInError.from_response(server_response.content, self.parent_srv.namespace, url)
 
                 raise ServerResponseError.from_response(server_response.content, self.parent_srv.namespace, url)
             except ParseError:

tableauserverclient/server/endpoint/exceptions.py

@@ -1,13 +1,20 @@
 from defusedxml.ElementTree import fromstring
-from typing import Optional
+from typing import Mapping, Optional, TypeVar
+
+
+def split_pascal_case(s: str) -> str:
+    return "".join([f" {c}" if c.isupper() else c for c in s]).strip()
 
 
 class TableauError(Exception):
     pass
 
 
-class ServerResponseError(TableauError):
-    def __init__(self, code, summary, detail, url=None):
+T = TypeVar("T")
+
+
+class XMLError(TableauError):
+    def __init__(self, code: str, summary: str, detail: str, url: Optional[str] = None) -> None:
         self.code = code
         self.summary = summary
         self.detail = detail
@@ -18,7 +25,7 @@ def __str__(self):
         return f"\n\n\t{self.code}: {self.summary}\n\t\t{self.detail}"
 
     @classmethod
-    def from_response(cls, resp, ns, url=None):
+    def from_response(cls, resp, ns, url):
         # Check elements exist before .text
         parsed_response = fromstring(resp)
         try:
@@ -33,6 +40,10 @@ def from_response(cls, resp, ns, url=None):
         return error_response
 
 
+class ServerResponseError(XMLError):
+    pass
+
+
 class InternalServerError(TableauError):
     def __init__(self, server_response, request_url: Optional[str] = None):
         self.code = server_response.status_code
@@ -51,6 +62,11 @@ class NotSignedInError(TableauError):
     pass
 
 
+class FailedSignInError(XMLError, NotSignedInError):
+    def __str__(self):
+        return f"{split_pascal_case(self.__class__.__name__)}: {super().__str__()}"
+
+
 class ItemTypeNotAllowed(TableauError):
     pass
 

test/test_auth.py

@@ -63,23 +63,23 @@ def test_sign_in_error(self):
         with requests_mock.mock() as m:
             m.post(self.baseurl + "/signin", text=response_xml, status_code=401)
             tableau_auth = TSC.TableauAuth("testuser", "wrongpassword")
-            self.assertRaises(TSC.NotSignedInError, self.server.auth.sign_in, tableau_auth)
+            self.assertRaises(TSC.FailedSignInError, self.server.auth.sign_in, tableau_auth)
 
     def test_sign_in_invalid_token(self):
         with open(SIGN_IN_ERROR_XML, "rb") as f:
             response_xml = f.read().decode("utf-8")
         with requests_mock.mock() as m:
             m.post(self.baseurl + "/signin", text=response_xml, status_code=401)
             tableau_auth = TSC.PersonalAccessTokenAuth(token_name="mytoken", personal_access_token="invalid")
-            self.assertRaises(TSC.NotSignedInError, self.server.auth.sign_in, tableau_auth)
+            self.assertRaises(TSC.FailedSignInError, self.server.auth.sign_in, tableau_auth)
 
     def test_sign_in_without_auth(self):
         with open(SIGN_IN_ERROR_XML, "rb") as f:
             response_xml = f.read().decode("utf-8")
         with requests_mock.mock() as m:
             m.post(self.baseurl + "/signin", text=response_xml, status_code=401)
             tableau_auth = TSC.TableauAuth("", "")
-            self.assertRaises(TSC.NotSignedInError, self.server.auth.sign_in, tableau_auth)
+            self.assertRaises(TSC.FailedSignInError, self.server.auth.sign_in, tableau_auth)
 
     def test_sign_out(self):
         with open(SIGN_IN_XML, "rb") as f: