Took the Replicator into use in avrorouter as an alternative to the
binlogrouter based setup. This also allows the avrorouter to automatically
handle master failovers and to start replication from GTID coordinates.
See script directory for method. The script to run in the top level
MaxScale directory is called maxscale-uncrustify.sh, which uses
another script, list-src, from the same directory (so you need to set
your PATH). The uncrustify version was 0.66.
The maxscale_is_shutting_down function is used to detect when MaxScale
should stop. This fixes a race condition in the code where the workers has
not yet been initialized but a termination signal has been received. It
also replaces the misuse of the service_should_stop variable with a proper
function.
The custom random number generator can now be replaced with a C++11
RNG. This greatly improves the reliability and trustworthiness of it.
In addition to this, the conversion of the RNG to a thread-local object
removes the race condition that was present in the previous
implementation. It also theoretically improves performance by a tiny bit.
This is the first step in some cleanup of the Worker interface.
The execution mode must now be explicitly specified, but that is
just a temporary step. Further down the road, _posting_ will
*always* mean via the message loop while _executing_ will optionally
and by default mean direct execution if the calling thread is that
of the worker.
The signal handler no longer acquires the service list lock which removes
a number of deadlock possibilities from the shutdown process. Instead, a
global shutdown flag is set that serves the same purpose as the individual
service shutdown flags did.
Relaced router_options with configuration parameters in the createInstance
router entry point. The same needs to be done for the filter API as barely
any filters use the feature.
Some routers (binlogrouter) still support router_options but using it is
deprecated. This had to be done as their use wasn't deprecated in 2.2.
The actual processing of the replicated events is now delegated to the Rpl
class. This class only deals with the raw binary format log events which
allows it to be used for both binlogs stored on disk as well as binlogs
that have just been replicated.
The RowEventConverter is now passed as a parameter to the Avro
instance. Wrapped the value in an std::auto_ptr to make the cleanup
automatic (when it is implemented).
Fixed a typo in the event handler member variable and removed the unused
stats member.
The file indexing provided very little benefit for the intended purpose of
the router. Removing it makes the whole system more robust and simplifies
the code by a large amount.
The code in avrorouter that returned the current transaction was not very
useful and it can be acquired via the REST API in a more convenient
format.
The number of created sessions is tracked on the service level so there is
no need to track it in the avrorouter.
Removed declarations for functions that do not exist and moved code around
to reduce the scope.
The code that handles the Avro files is now fully abstracted behind the
AvroConverter class that implements the RowEventHandler interface.
The code still has some avro specific behavior in a few places (parsing of
JSON files into TableCreate objects). This can be replaced, if needed, by
querying the master server for the CREATE TABLE statements.
