For external parsing there will be a separate process that handles
parse requests sent from MaxScale. From MaxScale's perspective there
will just be a specific query classifier plugin that upon startup
launches that external process and manages its lifetime. That is,
MaxScale proper will be completely oblivious of this arrangement.
The skeleton process introduced here does nothing; just sits in
a loop sleeping. The skeleton query classifier plugin currently
loads the MySQL embedded query classifier and performs parsing
using it. That way the external process based query classifier can
immediately be used.
Next step is to introduce process management into the picture without
actually moving the parsing anywhere.
The FindMariaDBConnector.cmake file now checks if the found library actually is
the MariaDB Connector-C library. If the found library is not the MariaDB
Connector-C, it will be built from source.
The include directories previously used by MaxScale were from the embedded
library. All parts of MaxScale apart from the query classifier now use
the client libraries.
Now, qc_mysqlembedded is linked against MySQL's embedded library,
and MaxScale itself against Connector-C.
So, in order to build MaxScale, Connector-C must be installed.
This has been tested with Connector-C 2.2.1.
The build variable MYSQLCLIENT_LIBRARIES is no longer used.
This is the first change in an attempt to arrange the linking so that
more errors are detected at link-time.
- All files in server/core but for gateway.c are linked to one shared
library called maxscale-common.
- The files log_manager/log_manager.cc and utils/skygw_utils.cc are
built into maxscale-common as well.
- MaxScale itself consists now only of gateway.c and is linked with
maxscale-common.
- All plugins link with maxscale-common.
- All executables link in addition with {EMBEDDED_LIB}.
After this change, the change (MXS-517) where query_classifier is the
only component that uses ${EMBEDDED_LIB} and the rest mysqlclient can
be made much cleaner.
After a few additional steps, all shared libraries can be linked with
the linker flags "-Wl,-z,defs", which directs the linker to resolve
all symbols. That will require that all shared libraries list all the
libraries they need, but will at the same time ensure that any
missing symbols are detected at link-time and not at run-time.
The mqfilter was not built by default even though it should have been. This has
been fixed but the filter is built only if librabbitmq is found. This was done
to avoid having the librabbitmq and its development headers as a hard
dependency.
The bundled PCRE2 library will be built as a separate target and configuring
CMake no longer builds it. Instead, it will only be built when it is out of date.
This requires all targets to declare that they depend on the pcre2 target in
order for it to be built.
