Event handling is now enabled by default. If the monitor cannot query the EVENTS-
table (most likely because of missing credentials), print an error suggesting to
turn the feature off.
When disabling events on a rejoining standalone server (likely a former master),
disable binlog event recording for the session. This prevents the ALTER EVENT
queries from generating binlog events.
Also added documentation and combined similar parts in the code.
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.
Since the servers are not modified before or during the wait, the waiting
can be done in the preparation method. This simplifies the actual failover
somewhat, and allows the monitor to keep running normally while waiting for
the log to clear.
No longer depends on monitor events as the other operations do not
either. The active_event/new_event detection was removed, as these
only protect against a rare situation. A similar feature which
protects all the cluster modifications will be implemented later.
When the replication status from the external master is checked, the
pending status must be used. This makes sure that the SlaveStatusArray and
the server state are sync.
Also extended the message that was logged when the external master was
lost. By adding the network address there, it makes it easier to see where
the server was replicating from if only the log file is available.
It does not save much in characters compared to std::function<void ()>
and it's a bit misleading as not just any callable object will do, but
only one that takes no argument and returns void.
In preparation for Worker::post() to be renamed to Worker:execute().
The concept of _posting_ will be reserved to mean the transfer of
something over the message queue to the worker for processing and
nothing else.
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 'events' and 'script' config values were defined for every monitor.
Removed the extra definitions and moved the variables to MXS_MONITOR.
MariaDBMonitor was printing config values a second time, they are
already printed by the caller.
Moved the events enum definition to the internal header since it's no longer
required by modules.
Added a default config setting "all" to 'events' to clarify that it enables
all events.
This reduces the ambiguity of server id:s in the slave status contents.
If a slave connection has been seen properly connected at an earlier time,
it can be trusted to report the correct master server id. This also
fixes some wrong status assignment edge cases with the SERVER_WAS_SLAVE-bit.
The bit will be removed in a later commit.
Even this does not solve the situation when MaxScale is started with
some servers down.
The function has use outside of the monitors as it makes execution of
worker tasks much more convenient. Currently, this change only moves the
code and takes it into use: there should be no functional changes.
Uses mostly the status functions for reading the flags. Strickly
speaking this breaks the REST API since in some cases (status combinations)
the printed string is different from what was printed before.
