[_688] impl raw _server_version

Author: d-w-moore

irods/connection.py

@@ -83,6 +83,8 @@ def __init__(self, pool, account):
         self._disconnected = False
 
         scheme = self.account._original_authentication_scheme
+        if self.pool and not self.pool._need_auth:
+            return
 
         # These variables are just useful diagnostics.  The login_XYZ() methods should fail by
         # raising exceptions if they encounter authentication errors.

irods/helpers/__init__.py

@@ -36,3 +36,13 @@ def xml_mode(s):
         yield
     finally:
         ET(None)
+
+
+@contextlib.contextmanager
+def attr_changed(obj, attrname, value):
+   old = getattr(obj, attrname, None)
+   try:
+       setattr(obj, attrname, value)
+       yield
+   finally:
+       setattr(obj, attrname, old)

irods/pool.py

@@ -1,3 +1,4 @@
+import contextlib
 import datetime
 import logging
 import threading
@@ -57,6 +58,7 @@ def __init__(
             or application_name
             or DEFAULT_APPLICATION_NAME
         )
+        self._need_auth = True
 
         if connection_refresh_time > 0:
             self.refresh_connection = True
@@ -65,6 +67,15 @@ def __init__(
             self.refresh_connection = False
             self.connection_refresh_time = None
 
+    @contextlib.contextmanager
+    def no_auto_authenticate(self):
+        import irods.helpers
+        with irods.helpers.attr_changed(self, '_need_auth', False):
+            yield self
+
+    def set_session_ref(self, session):
+        self.session_ref = weakref.ref(session) if session is not None else lambda: None
+
     @property
     def _conn(self):
         return getattr(self._thread_local, "_conn", None)

irods/session.py

@@ -1,5 +1,6 @@
 import ast
 import atexit
+import contextlib
 import copy
 import errno
 import json
@@ -69,6 +70,16 @@ class NonAnonymousLoginWithoutPassword(RuntimeError):
     pass
 
 
+@contextlib.contextmanager
+def attr_changed(obj, attrname, value):
+   old = getattr(obj, attrname, None)
+   try:
+       setattr(obj, attrname, value)
+       yield
+   finally:
+       setattr(obj, attrname, old)
+
+
 class iRODSSession:
 
     def library_features(self):
@@ -354,11 +365,36 @@ def port(self):
         return self.pool.account.port
 
     @property
-    def server_version(self):
+    def server_version(self): return self._server_version()
+
+    def raw_server_version(self):
+        """Returns the same version tuple as iRODSSession's server_version property, but
+           does not require successful authentication.
+        """
+        import irods.connection
+        with self.clone().pool.no_auto_authenticate() as pool:
+            return irods.connection.Connection(
+                pool, pool.account
+            ).server_version
+
+    RAW_SERVER_VERSION = staticmethod(lambda s:s.raw_server_version())
+
+    def _server_version(self, version_func = None):
+        """The  server version can be retrieved by the usage
+            session._server_version()
+        with conditional substitution by another version by use of the environment variable:
+            PYTHON_IRODSCLIENT_REPORTED_SERVER_VERSION.
+
+        Also: if iRODSServer.RAW_SERVER_VERSION is passed in version_func, the true server
+        version can be accessed without first going through authentication.
+        Example:
+            ses = irods.helpers.make_session()
+            vsn = ses._server_version( ses.RAW_SERVER_VERSION )
+        """
         reported_vsn = os.environ.get("PYTHON_IRODSCLIENT_REPORTED_SERVER_VERSION", "")
         if reported_vsn:
             return tuple(ast.literal_eval(reported_vsn))
-        return self.__server_version()
+        return self.__server_version() if version_func is None else version_func(self)
 
     def __server_version(self):
         try:

irods/test/connection_test.py

@@ -1,11 +1,16 @@
 #! /usr/bin/env python
 
+import numbers
 import os
 import sys
 import tempfile
 import unittest
-from irods.exception import NetworkException
 from irods import MAXIMUM_CONNECTION_TIMEOUT
+from irods.exception import (
+    NetworkException,
+    CAT_INVALID_AUTHENTICATION
+)
+import irods.session
 import irods.test.helpers as helpers
 from irods.test.helpers import (
     server_side_sleep,
@@ -34,6 +39,29 @@ def test_connection_destructor(self):
         self.assertTrue(conn._disconnected)
         conn.release(destroy=True)
 
+    def test_server_version_without_authentication__issue_688 (self):
+        sess = self.sess
+
+        # Make a session object that cannot authenticate.
+        non_authenticating_session = irods.session.iRODSSession(
+            host = sess.host,
+            port = sess.port,
+            user = sess.username,
+            zone = sess.zone,
+            # No password.
+        )
+
+        # Test raw_server_version method returns a value.
+        version_tup = non_authenticating_session.raw_server_version()
+
+        # Test returned value is non-empty "version" tuple, i.e. holds only integer values.
+        self.assertTrue(len(version_tup) > 0)
+        self.assertFalse(any(not isinstance(_, numbers.Integral) for _ in version_tup))
+
+        # Test that the older server_version property fails for the unauthorized session object.
+        with self.assertRaises(CAT_INVALID_AUTHENTICATION):
+            non_authenticating_session.server_version
+
     def test_failed_connection(self):
         # Make sure no connections are cached in self.sess.pool.idle to be grabbed by get_connection().
         # (Necessary after #418 fix; make_session() can probe server_version, which then leaves an idle conn.)