If a module command returns a json object, it will always be
returned to the caller, irrespective of whether the command
itself succeeded or not.
Otherwise, if the command failed and if the module command has
set an error message, that error message will be returned as a
json object containing the error message.
Since the module command interface was expanded to include a JSON output
parameter, there is no longer a need for an output DCB. As the JSON can be
printed by both maxadmin and the REST API, this allows the removal of
explicit output formatting in module commands.
The `script_timeout` and `journal_max_age` parameters weren't handled in
the monitor alteration code.
Also added missing documentation to maxadmin help output for
`alter monitor`.
The `add user` and `enable account` commands create fully privileged
administrative users like they did in 2.1. This makes the addition of
read-only users backwards compatible.
Updated and expanded the documentation on administrative interface
users. Added entries into the release notes as well as the upgrading
document about relevant changes between 2.1 and 2.2.
Removing the last admin account is now forbidden. This should prevent most
cases where users could lock themselves out of the administrative
interface.
This change does allow a non-root network user to be the last admin
account. In practice this does not prevent the root user from gaining
access to maxadmin. Access can be gained by removing the users file and
restarting MaxScale or by editing the users file by hand.
MaxAdmin can now create basic users for both network and UNIX domain
socket use. Currently the basic and admin types have the same permissions
in maxadmin but for the REST API, only admin accounts can modify MaxScale.
The users are now stored as an array of JSON objects. Legacy users are
automatically upgraded once they are loaded and a backup of the original
users file is created.
Removed the password parameter from the `remove user` maxadmin command as
well as all of the relevant functions. Requiring that an administrator
knows the password of the account to be deleted is not a sound requirement
now that, at least in theory, two types of accounts can be created.
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.
