Bug: gateway setSecure may leak Communicators

[jamoore]

The BlitzGateway.setSecure method should almost certainly call self.c.closeSession() (or self.c.__del__()) before re-assigning the self.c value.

    def setSecure (self, secure=True):
        """ 
        Switches between SSL and insecure (faster) connections to Blitz.
        The gateway must already be connected.
        
        @param secure:  If False, use an insecure connection
        @type secure:   Boolean
        """
        if hasattr(self.c, 'createClient') and (secure ^ self.c.isSecure()):
            self.c = self.c.createClient(secure=secure)
            self._createProxies()
            self.secure = secure

See: #2007 for the root cause of the leak.

[jmoore]

Will, this is a quite easy fix, but is quite important. (I've gone over the repercussions with Carlos). If you'd like to discuss, please let me know.

[wmoore]

Making either of the suggested changes, self.c.closeSession() or self.c.del() causes gateawaytest connection tests to fail...

    def setSecure (self, secure=True):
        """ 
        Switches between SSL and insecure (faster) connections to Blitz.
        The gateway must already be connected.
        
        @param secure:  If False, use an insecure connection
        @type secure:   Boolean
        """
        if hasattr(self.c, 'createClient') and (secure ^ self.c.isSecure()):
            #self.c.closeSession()
            self.c.__del__()
            self.c = self.c.createClient(secure=secure)
            self._createProxies()
            self.secure = secure

Test failures below - all tests fail:

wjm:OmeroPy will$ python test/gatewaytest/connection.py
Can not connect
ECan not connect
ECan not connect
ECan not connect
E
======================================================================
ERROR: testMiscellaneous (__main__.ConnectionMethodsTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "test/gatewaytest/connection.py", line 20, in setUp
    super(ConnectionMethodsTest, self).setUp()
  File "/Users/will/Desktop/OMERO/components/tools/OmeroPy/build/lib/omero/gateway/scripts/testdb_create.py", line 54, in setUp
    self.prepTestDB()
  File "/Users/will/Desktop/OMERO/components/tools/OmeroPy/build/lib/omero/gateway/scripts/testdb_create.py", line 126, in prepTestDB
    dbhelpers.bootstrap()
  File "/Users/will/Desktop/OMERO/components/tools/OmeroPy/build/lib/omero/gateway/scripts/dbhelpers.py", line 381, in bootstrap
    if not u.create(client):
  File "/Users/will/Desktop/OMERO/components/tools/OmeroPy/build/lib/omero/gateway/scripts/dbhelpers.py", line 127, in create
    a = client.getAdminService()
AttributeError: 'NoneType' object has no attribute 'getAdminService'

======================================================================
ERROR: testMultiProcessSession (__main__.ConnectionMethodsTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "test/gatewaytest/connection.py", line 20, in setUp
    super(ConnectionMethodsTest, self).setUp()
  File "/Users/will/Desktop/OMERO/components/tools/OmeroPy/build/lib/omero/gateway/scripts/testdb_create.py", line 54, in setUp
    self.prepTestDB()
  File "/Users/will/Desktop/OMERO/components/tools/OmeroPy/build/lib/omero/gateway/scripts/testdb_create.py", line 126, in prepTestDB
    dbhelpers.bootstrap()
  File "/Users/will/Desktop/OMERO/components/tools/OmeroPy/build/lib/omero/gateway/scripts/dbhelpers.py", line 381, in bootstrap
    if not u.create(client):
  File "/Users/will/Desktop/OMERO/components/tools/OmeroPy/build/lib/omero/gateway/scripts/dbhelpers.py", line 127, in create
    a = client.getAdminService()
AttributeError: 'NoneType' object has no attribute 'getAdminService'

======================================================================
ERROR: testSeppuku (__main__.ConnectionMethodsTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "test/gatewaytest/connection.py", line 20, in setUp
    super(ConnectionMethodsTest, self).setUp()
  File "/Users/will/Desktop/OMERO/components/tools/OmeroPy/build/lib/omero/gateway/scripts/testdb_create.py", line 54, in setUp
    self.prepTestDB()
  File "/Users/will/Desktop/OMERO/components/tools/OmeroPy/build/lib/omero/gateway/scripts/testdb_create.py", line 126, in prepTestDB
    dbhelpers.bootstrap()
  File "/Users/will/Desktop/OMERO/components/tools/OmeroPy/build/lib/omero/gateway/scripts/dbhelpers.py", line 381, in bootstrap
    if not u.create(client):
  File "/Users/will/Desktop/OMERO/components/tools/OmeroPy/build/lib/omero/gateway/scripts/dbhelpers.py", line 127, in create
    a = client.getAdminService()
AttributeError: 'NoneType' object has no attribute 'getAdminService'

======================================================================
ERROR: testTopLevelObjects (__main__.ConnectionMethodsTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "test/gatewaytest/connection.py", line 20, in setUp
    super(ConnectionMethodsTest, self).setUp()
  File "/Users/will/Desktop/OMERO/components/tools/OmeroPy/build/lib/omero/gateway/scripts/testdb_create.py", line 54, in setUp
    self.prepTestDB()
  File "/Users/will/Desktop/OMERO/components/tools/OmeroPy/build/lib/omero/gateway/scripts/testdb_create.py", line 126, in prepTestDB
    dbhelpers.bootstrap()
  File "/Users/will/Desktop/OMERO/components/tools/OmeroPy/build/lib/omero/gateway/scripts/dbhelpers.py", line 381, in bootstrap
    if not u.create(client):
  File "/Users/will/Desktop/OMERO/components/tools/OmeroPy/build/lib/omero/gateway/scripts/dbhelpers.py", line 127, in create
    a = client.getAdminService()
AttributeError: 'NoneType' object has no attribute 'getAdminService'

----------------------------------------------------------------------
Ran 4 tests in 2.000s

FAILED (errors=4)
wjm:OmeroPy will$ 

[jmoore]

Can't close the session while you still need it. Maybe something like:

        if hasattr(self.c, 'createClient') and (secure ^ self.c.isSecure()):
            oldC = self.c
            self.c = oldC.createClient(secure=secure)
            oldC.__del__() # only needs to be called if previous doesn't throw
            self._createProxies()
            self.secure = secure

[Will Moore <will@…>]

(In [8d81854f9529f76685f85abc6209f8db91af0f53/ome.git] on branch develop) Old connections deleted in Blitz setSecure(). Closes #5723