[#418] raise error in test for IRODS_VERSION mismatch

We now probe the server_version in each test and quit if the
server is too recent, a strong reminder to update the IRODS_VERSION
in the StartupPack.

That probing initially caused test_failed_connection not to pass, due
to its implicit assumption of an empty idle pool - also fixed in this commit.

Author: d-w-moore

irods/test/connection_test.py

@@ -30,6 +30,9 @@ def test_connection_destructor(self):
         conn.release(destroy=True)
 
     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.)
+        self.sess.cleanup()
         # mess with the account's port
         saved_port = self.sess.port
         self.sess.pool.account.port = 6666

irods/test/helpers.py

@@ -1,4 +1,5 @@
 from __future__ import absolute_import
+from __future__ import print_function
 import os
 import io
 import tempfile
@@ -13,12 +14,26 @@
 import random
 import datetime
 import json
+import sys
 from irods.session import iRODSSession
-from irods.message import iRODSMessage
+from irods.message import (iRODSMessage, IRODS_VERSION)
 from irods.password_obfuscation import encode
 from six.moves import range
 
 
+class StopTestsException(Exception):
+
+    def __init__(self,*args,**kwargs):
+        super(StopTestsException,self).__init__(*args,**kwargs)
+        if 'unittest' in sys.modules.keys():
+            print("Aborting tests [ Got : %r ]" % self, file = sys.stderr)
+            os.abort()
+
+
+class iRODS_Server_Too_Recent(StopTestsException):
+    pass
+
+
 def my_function_name():
     """Returns the name of the calling function or method"""
     return inspect.getframeinfo(inspect.currentframe().f_back).function
@@ -87,15 +102,27 @@ def recast(k):
     return (config, auth)
 
 
-def make_session(**kwargs):
+# Create a connection for test, based on ~/.irods environment by default.
+
+def make_session(test_server_version = True, **kwargs):
     try:
         env_file = kwargs.pop('irods_env_file')
     except KeyError:
         try:
             env_file = os.environ['IRODS_ENVIRONMENT_FILE']
         except KeyError:
             env_file = os.path.expanduser('~/.irods/irods_environment.json')
-    return iRODSSession( irods_env_file = env_file, **kwargs )
+    session = iRODSSession( irods_env_file = env_file, **kwargs )
+
+    if test_server_version:
+        connected_version = session.server_version[:3]
+        advertised_version = IRODS_VERSION[:3]
+        if connected_version > advertised_version:
+            msg = ("Connected server is {connected_version}, "
+                   "but this python-irodsclient advertises compatibility up to {advertised_version}.").format(**locals())
+            raise iRODS_Server_Too_Recent(msg)
+
+    return session
 
 
 def home_collection(session):