The routers no longer need to track the number of errors each DCB
receives. This is now done by the protocol modules.
The type of the DCB no longer needs to be checked in the handleError
implementation as the function is only called when a backend DCB fails.
The highwater and lowwater callbacks were never registered for the client
DCBs in the binlogrouter.
The DCB hangup callbacks were never called by the core and were replaced
with fake hangup events in an earlier version.
Moved some typedefs to router.h and server.h, changed a few
constants to these enums. Renamed some types in config.h to
remove "Gateway".
There are still some functions in the public header which are
only used in core, but they seem to fit the theme of public functions
so were not moved.
All modules now declare a name for the module. This is name is added as a
prefix to all messages logged by a module. The prefix should help
determine which part of the system logs a message.
The MXS_MODULDE object now contains optinal pointers for functions
to be called att process and thread startup and shutdown. Since the
functions were added to the end, strictly speaking, all structures
would not have needed to have been modified, but better to be
explicit. In a subsequent change, these will be called.
C++ does not support flexible arrays, so for the time being C++
modules are restricted to 10 parameters. Better approach is to
factor out the parameters to a separate array and then just store
a pointer to that array in MXS_MODULE.
The MODULE_INFO is now the main object which is used by modules to convey
information to the MaxScale core. The MXS_MODULE name is more apt as it
now contains the actual module definition.
The old MODULES structure was moved into load_utils.c as an internal
implementation and was renamed so that it is not confused with the new
MODULE structure.
The modules are now declared with a common macro. This allows future
additions to the module loading process while also making the loaded
symbol name a constant.
This allows modules to only expose one entry point with a consistent
signature. In the future, this could be used to implement declarations of
module parameters.
Binlog server option ‘encryption_key_file=’ can now use the same key
file the MariaDB 10.1 server might have in my.cnf:
‘file_key_management_filename=‘
Note: the file content must be in clear, no key encryption.
The backend MySQL protocol module now supports a new routing capability
which allows result sets to be gathered into one buffer before they are
routed onward. This should not be used by modules that expect large
result sets as the result set is buffered in memory.
Adding a limit on how large of a result set could be buffered would allow
relatively safe use of this routing capability without compromising the
stability of the system.
Storing the large events in memory allows checksum calculations to be done
in one step. This also makes the encryption of events easier as they
require the complete event in memory.
The backend protocol module can be requested to provide complete and
contiguous packets to the router module. This removes the need to process
the packets in binlogrouter.
