Properly parse ISO date strings (#473)

Pre Python 3.11 the `datetime.fromisoformat` isn't a generic date time
parser and can only be used to parse ISO dates generated by the python
`datatime` module. This PR normalized the date string the same way the
google oauth2 library does by discarding the timezone and millisecond
part of the date string.

## Changes
Make date parsing for tokens from the CLI more robust

## Tests
* Added unit test
* Manually tested with CLI auth provider

databricks/sdk/core.py

@@ -346,7 +346,8 @@ def __init__(self, cmd: List[str], token_type_field: str, access_token_field: st
 
     @staticmethod
     def _parse_expiry(expiry: str) -> datetime:
-        for fmt in ("%Y-%m-%d %H:%M:%S.%f", "%Y-%m-%d %H:%M:%S", "%Y-%m-%dT%H:%M:%S.%f%z"):
+        expiry = expiry.rstrip("Z").split(".")[0]
+        for fmt in ("%Y-%m-%d %H:%M:%S", "%Y-%m-%dT%H:%M:%S"):
             try:
                 return datetime.strptime(expiry, fmt)
             except ValueError as e:

tests/test_core.py

@@ -6,6 +6,7 @@
 import random
 import string
 import typing
+from datetime import datetime
 from http.server import BaseHTTPRequestHandler
 from typing import Iterator, List
 
@@ -14,10 +15,10 @@
 
 from databricks.sdk import WorkspaceClient
 from databricks.sdk.azure import ENVIRONMENTS, AzureEnvironment
-from databricks.sdk.core import (ApiClient, Config, CredentialsProvider,
-                                 DatabricksCliTokenSource, DatabricksError,
-                                 HeaderFactory, StreamingResponse,
-                                 databricks_cli)
+from databricks.sdk.core import (ApiClient, CliTokenSource, Config,
+                                 CredentialsProvider, DatabricksCliTokenSource,
+                                 DatabricksError, HeaderFactory,
+                                 StreamingResponse, databricks_cli)
 from databricks.sdk.service.catalog import PermissionsChange
 from databricks.sdk.service.iam import AccessControlRequest
 from databricks.sdk.version import __version__
@@ -52,6 +53,14 @@ def test_databricks_cli_token_source_not_installed(config, monkeypatch):
         DatabricksCliTokenSource(config)
 
 
+@pytest.mark.parametrize("date_string,expected",
+                         [("2023-12-01T15:19:48.007742617Z", datetime(2023, 12, 1, 15, 19, 48)),
+                          ("2023-12-05T15:59:01.40081+11:00", datetime(2023, 12, 5, 15, 59, 1)),
+                          ("2023-12-06 10:06:05", datetime(2023, 12, 6, 10, 6, 5))])
+def test_databricks_cli_token_parse_expiry(date_string, expected):
+    assert CliTokenSource._parse_expiry(date_string) == expected
+
+
 def write_small_dummy_executable(path: pathlib.Path):
     cli = path.joinpath('databricks')
     cli.write_text('#!/bin/sh\necho "hello world"\n')