How does the Cassandra C++ Driver use the zlib library?

The Cassandra C++ Driver has an option used to enable the zlib library:

--ENABLE-ZLIB                     Enable zlib

Only they do not say what they are doing with it.

Anyone knows what that option gives us?

Does it precompresses the data before sending it to the backend? What else would it use zlib for? Looking at the source of the C++ driver, I can see the zlib option in the CMakeLists.txt:

option(CASS_USE_ZLIB "Use zlib" OFF)

But the C++ source has no #include <zlib.h> so I'm wondering whether there is any code actually using the library (maybe it was intended but never implemented?)

Solution

The driver does not currently use zlib; it is there for future work. CPP-103 will add compression support to the driver which will utilize zlib at that time. It remained in the build system due to legacy implementation and can safely be ignored.

If you would like to see this feature implemented please vote or comment on the JIRA issue.