If a destroyed monitor is created again, it will be reused. This should
prevent excessive memory growth when the same monitor is created and
destroyed again.
The feedback system wasn't used and was starting to cause problems on
Debian 9 where the libcurl required different version of OpenSSL than what
MaxScale was linked against.
The module commands can now produce JSON formatted output which is passed
to the caller. The output should conform to the JSON API as closely as
possible.
Currently, the REST API wraps all JSON produced by module commands inside
a meta-object of the following type:
{
"meta": <output of module command>
}
This allows the output to be JSON API conformant without modifying the
modules and allows incremental updates to code.
The `monitoruser` and `monitorpw` parameters were mislabeled as `monuser`
and `monpw`. To allow backwards compatibility, the `monuser` and `monpw`
still work as aliases for the correct commands.
A set of the core MaxScale parameters can now be altered at runtime. This
set consists of the authentication timeouts and the admin interface
authentication. Other parameters either can't be modified due to internal
limitations or aren't sensible to modify at runtime.
Preparation for adding KILL syntax support.
Session id changed to uint32 everywhere. Added atomic op.
Session id can be acquired before session_alloc().
Added session_alloc_with_id(), which is given a session id number.
Worker object has a session_id->SESSION* mapping, not used yet.
Now possible to send a function and arguments to a specific worker
thread for execution.
In particular, this will be used for transferring the injection of
fake hangup events into DCBs, related to a particular server, from
the monitor thread to the worker threads, thus removing the need
for locks.
MXS_WORKER is an abstraction of a worker aka worker thread.
It has a pipe whose read descriptor is added to the worker/thread
specific poll set and a write descriptor used for sending messages
to the worker.
The worker exposes a function mxs_worker_post_message using which
messages can be sent to the worker. These messages can be sent from
any thread but will be delivered on the thread dedicated for the
worker.
To illustrate how it works, maxadmin has been provided with a new
command "ping workers" that sends a message to every worker, which
then logs a message to the log.
Additional refactoring are needed, since there currently are overlaps
and undesirable interactions between the poll mechanism, the thread
mechanism and the worker mechanism.
This is visible currently, for instance, by it not being possible to
shut down MaxScale. The reason is that the workers should be shut down
first, then the poll mechanism and finally the threads. The shutdown
need to be arranged so that a shutdown message is sent to the workers
who then cause the polling loop to exit, which will cause the threads
to exit.
That can be arranged cleanly by making poll_waitevents() a "method"
of the worker, which implies that the poll set becomes a "member
variable" of the worker.
To be continued.
The help messages are now more descriptive and have usage information in
them. This should help users use the commands without relying on the
online documentation.
The authenticators should have a similar way to print diagnostic
information as filter and routers do. This allows the authenticators to
print the users in their own format.
In the future, all the diagnostic entry points should be changed so that
they return a structure that contains the information in a standard
form. This information can then be formatted in different ways by other
modules.
They are not particularly useful, they surely are not used
and impose a small cost for every event extracted from the
poll sets.
This commit only removes the maxadmin commands, subsequent
commits will remove the actual code.
This header defines some general functions and maxscale main() return
values. Most of it is still public, but there were some functions
which were moved to a core header.
The external config.h header defined functions and structures that are
intended to be used by modules. The internal header contains functions
that are used only by the MaxScale core.
To test the configuration validation and default value generation, the
functions needed to be refactored to allow parameters to be passed
directly to the function.
Some uses of monitorStart didn't pass the monitor parameters to the
function call. This caused runtime configuration of monitors to not have
any parameters as they never got their parameters.
Using the unique ID for the session is easier to use than an address. This
also allows the removal of all pointer values from the maxadmin output
which is never useful to the end user.
After upgrades, it is usually useful to see which version of MaxScale is
running. By adding a command, we can see the actual version of the running
daemon process instead of the version of the current binary.
The detailed output of the new help command was a bit too densely packed
for some commands.
Added missing values for the `alter server` command help output.
Adding a server to multiple monitors is forbidden. This should be detected
and reported to the end user.
The information provided by the config_runtime system to the client isn't
as detailed as it could be. Some sort of an error message stack should be
added so that client facing interfaces could properly report the reason
for the failure. Currently the only way to detect the reason of the
failure is to parse the log files.
The errors were detected but the code proceeded to call various functions
with bad pointers. This led to a crash if a bad server name was given to
'show server'.
The module commands operations are now listed as `commands` instead of
`functions`. The output was also formatted and an optional filtering was
added to the `list commands` call.
