Hello Thierry, I am not rewriting ldapadd,... methods of "real" DS class, I am in fact creating MockDS class with custom ldapadd,... methods, _just_ like you suggest :) Furthermore, you can view it as a subclass of "real_ds" - even though it is not a proper Python subclass, it inherits all functions from repl module just like "real_ds" would (again through ModuleProxy mechanism). So, methods that are defined in repl are the same for "real_ds" class and for MockDS class, but ldap.. methods are different. So, basically exactly what you suggest :) Code of the whole class along with all methods is in file tests/test_dsmodules/conftest.py line 7. Thank you, Jan On 10/28/2013 12:02 PM, thierry bordaz wrote: > Hi Jan, > > That is very impressive POC, far above my skill in python. Thanks for > sharing this. > I have a novice question. > This implementation overwrites the basic ldapadd,ldapsearch... function of > the "real" DS. > An other approach is to write a 'mock_ds' class being a subclass of > 'real_ds' and to overwrite the ldapadd,ldapsearch in mock_ds class (to store > data into a dict). What would be the advantages of your approach ? > > best regards > thierry > > On 10/25/2013 09:36 PM, Jan Rusnacko wrote: >> Hello Roberto and Thierry, >> >> as I promised, I am sending you a proof-of-concept code that demonstrates, how >> we can mock DS in unit tests for library function (see attachment). You can run >> tests just by executing py.test in tests directory. >> >> Only 3 files are of interest here: >> >> lib389/dsmodules/repl.py - this is a Python module with functions - they expect >> DS instance as the first argument. Since they are functions, not methods, I can >> just mock DS and pass that fake one as the first argument to them in unit tests. >> >> tests/test_dsmodules/conftest.py - this file contains definition of mock DS >> class along with py.test fixture, that returns it. >> >> tests/test_dsmodules/test_repl.py - this contains unit tests for functions from >> repl.py. >> >> What I do is quite simple - I override ldapadd, ldapdelete .. methods of mock DS >> class, so that instead of sending command to real DS instance, they just store >> the data in 'dit' dictionary (which represents content stored in DS). This way, >> I can check that when I call e.g. function enable_changelog(..), in the end DS >> will have correct changelog entry. >> >> To put it very bluntly - enable_changelog(..) function just adds correct >> changelog entry to whatever is passed to it as the first argument. In unit >> tests, it is mock DS, otherwise it would be real DS class that sends real ldap >> commands to real DS instance behind. >> >> Now I can successfully test that enable_changelog really works, without going >> into trouble defining DSInstance or ldap calls at all. Also, I believe this >> approach would work for 95% of all functions in lib389. Another benefit is that >> unit tests are much faster, than on real DS instance. >> >> Sidenote: even though everything is defined in separate namespace of 'repl' >> module as function, in runtime they can be used as normal methods of class >> DSInstance. That is handled by DSModuleProxy. We already went through this, but >> not with Roberto. >> >> Hopefully, now with some code in our hands, we will be able to understand each >> other on this 'mocking' issue and come to conclusions more quickly. >> >> Let me know what you think. >> >> Thank you, >> Jan > -- 389-devel mailing list 389-devel@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/389-devel
