Always storing runtime configuration changes prevents problems when the
change causes another parameter to change. One example of this is
transaction_replay that implicitly enables other parameters.
Added a new module parameter type to be used for parameters
that specify a duration. With the suffixes 'h', 'm', 's' and
'ms' the duration can be specified in hours, minutes, seconds
or milliseconds, respectively.
Irrespective of how the duration is specified, it is always
returned as milliseconds.
For backward compatibility, when a duration value is read it must
be specifed how a value *not* defined using a suffix should be
interpreted; as seconds or milliseconds.
value = param->get_duration(name, mxs::config::INTERPRET_AS_SECONDS);
When the servers of a service are defined by a monitor, then
at startup all servers of the monitor should be added to relevant
services. Likewise, when a server is added to or removed from a
monitor at runtime, those changes should affect services as well.
However, whether that should happen or not depends upon the monitor.
In the case of the Clustrix monitor this should not happen as it
adds and removes servers depending on the runtime state of the
Clustrix cluster.
The services whose servers are defined using a monitor, will
now be populated from the monitor.
Note, no consideration has yet been given to runtime changes.
The manipulation functions are currently static so that the container can be initialized
if required. This will be fixed later.
The new functions are taken into use in monitor management.
Replaces uses of config_get_param() in modules either with contains()
or get_string(). The config_get_param() is moved to internal headers,
as it allows seeing inside a config setting.
Names starting with '@@' can now longer be used in configuration files.
Subsequent commits will prevent such names from being used when objects
are created dynamically.
The class MonitorManager contains monitor-related functions that should not
be called from modules. MonitorManager can access private fields and methods
of the monitor.
Most of the ones still remaining outside are special cases.
Also, removed locking from status manipulation functions as it
has not been required for quite some time.
The log message should now contain enough information to more easily debug
any configuration issues that result from updating the main config file
after runtime changes have been done.
Also fixed the theoretical race condition in detection of persisted
configuration files by only checking for their existence once.
All global parameters are now handled by the runtime configuration
modification code. The parameters that are trivial to update can now be
updated at runtime. All other global parameters cause a new error message
to be returned stating that the parameter in question cannot be modified
at runtime.
Also updated the list of modifiable parameters in MaxCtrl. This list
should not be stored in MaxCtrl and should be created by MaxScale at
runtime.
