Supvisors

* Refactoring of the **Supvisors** internal communications.
The `internal_port` of the **Supvisors** section in the Supervisor configuration file is no longer needed.
As a consequence, the `supvisors_list` option is simplified as follows: `<identifier>host_name:http_port`.
The transitional `SupvisorsInstanceStates.ISOLATING` state has been removed.
The remote **Supvisors** instance becomes `SILENT` as soon as the published events fails due to a transport issue.

* Implement [Issue 50](https://github.com/julien6387/supvisors/issues/50).
A new tag `operational_status` in the Application rules allows to declare the formula applicable to evaluate the
application operational status.
`status_formula` is added to the result of the XML-RPC `get_application_rules`.

* Implement [Issue 15](https://github.com/julien6387/supvisors/issues/15).
A `StarterModel` has been added to **Supvisors** to give a prediction of the application distribution when started.
The command is available through the new XML-RPCs `test_start_application` and `test_start_process` and have been
added to `supervisorctl`.

* The **Supvisors** `core_identifiers` option and the **Supvisors** rules can now accept indifferently Supervisor
identifiers or keys with the `host:http_port` format.

* Update the `get_instance_info` XML-RPC so that the function accepts a stereotype as parameter.
As a consequence, it now returns a list of dictionaries.

* Add a `lazy` attribute to the `update_numprocs` XML-RPC, so that when set combined to a numprocs decrease,
**Supvisors** defers the obsolete processes deletion from the Supervisor configuration only when the processes stop
(exit, crash or later user request) instead of stopping them immediately.

* Add monotonic time in internal model and exchanges to cope with time updates while **Supvisors** is running.
Impact on the XML-RPC `get_instance_info`, `get_process_info` and on the event interface for instance status
and process event.

* Add new `get_statistics_status`, `enable_host_statistics`, `enable_process_statistics`, `update_collecting_period`
XML-RPCs to support the possibility to get and update the collection of host and process statistics.
The corresponding commands `stats_status`, `enable_stats` and `stats_period` have been added to `supervisorctl`.
The JAVA client includes the new XML-RPCs.

* Add new `get_all_inner_process_info` and `get_inner_process_info` XML-RPCs to support debug investigation.
They return internal information on the processes declared on a **Supvisors** instance.

* Move the host statistics collector to the statistics collector process.
The option `stats_collecting_period` is now applicable to host statistics collector.

* Re-apply the eventual process `extra_args` when restarting the application.

* In the Supervisors navigation menu of the Web UI, add a red light to Supervisor instances having raised a failure.

* Allow the display of a software name and icon at the top of the **Supvisors** Web UI.
The options `software_name` and `software_icon` have been added to the **Supvisors** section of the Supervisor
configuration file.

* All internal identifiers are now based on the `host:http_port` format.

* Rename the `DEPLOYMENT` state as `DISTRIBUTION` state to lift ambiguity ("deployment" is rather connoted when dealing
with the orchestration domain).

* Rework **Supvisors** `RPCInterface` exceptions.

* Rework the Web UI.

* Fix bug that was randomly blocking **Supvisors** on restart or shutdown, due to a stdout flush hanging in
multiprocessing bowels. The statistics Process is now started before any other thread.

* `guest` time removed from because CPU calculation because it is already accounted in `user` time on Linux.

* Fix process CPU so that it corresponds to the Linux `top` result.

* Use the latest versions of Sphinx-related modules for documentation, as `sphinx-5.0` is now the minimal dependency.

* Fix regression when displaying the Network statistics in the **Supvisors** Web UI.

* Add restrictions to `flask-restx` dependencies.

* Fix rare I/O exception by joining the `SupervisorsProxy` thread before exiting the `SupvisorsMainLoop`.

* Fix rare exception when host network statistics are prepared for display in the **Supvisors** Web UI in the event
where network interfaces have different history sizes.

* Fix the **Supvisors** identifier possibilities when using the distribution rule `SINGLE_INSTANCE`.

* Update the process statistics collector thread so that it exits by itself when `supervisord` is killed.

* Improve the node selection when using the distribution rule `SINGLE_NODE`.

* Use an asynchronous server in the **Supvisors** internal communications.
The refactoring fixes an issue with the TCP server that sometimes wouldn't bind despite the `SO_REUSEADDR` set.

* Restore the `action` class in the HTML of the **Supvisors** Web UI.

* CI targets added for Python 3.11 and 3.12.

* Fix [Issue 112](https://github.com/julien6387/supvisors/issues/112).
Write the disabilities file even if no call to `disable` and `enable` XML-RPCs have been done.
Try to create the folder at startup if it does not exist.

* Fix a case where the `Starter` would block if the process reaches the expected state without reception
of the corresponding event.

* Fix typo for `zmq` requirement when installing **Supvisors** from `pypi`.

* Fix `flask-restx` dependency in setup according to Python version.

* Fix uncaught exception the request to start a process is rejected due to a lack of resources.
The exception was dependent from the Python version (absent in 3.6 but raised in 3.9).

* Monkeypatch fix of [Supervisor Issue 1596](https://github.com/Supervisor/supervisor/issues/1596).
Shutdown of the asyncore socket before it is closed.

* Improve robustness against network failures. All Supervisor events are applied to the local **Supvisors** instance
before they are published, so that it remains functional despite a network failure.
The internal TCP sockets are rebound when a network interface becomes up (requires `psutil`).

* Provide a discovery mode where the **Supvisors** instances are added on-the-fly without declaring them in
the `supvisors_list` option. The function relies on a Multicast Group definition (options `multicast_group`,
`multicast_interface` and `multicast_ttl` added to that purpose).
The attribute `discovery_mode` is added to the `get_state` and `get_instance_info` XML-RPCs.

* Add a new option `stereotypes` to support the discovery mode. The `identifiers` of the Application and Program rules
can now reference a **Supvisors** stereotype in addition to identifiers and aliases.
By extension, it is made available to the non-discovery mode.

* Add a new option `syncho_options` to enable the user to choose the conditions putting an end to the **Supvisors**
synchronization phase.
More particularly when using the new `USER` condition, the **Supvisors** Web UI provides a means to end the
`INITIALIZATION` state, with optional *Master* selection. The command is also available as an XML-RPC `end_synchro`
and has been added to `supervisorctl`.

* The new item `` in the `identifiers` of the Program rules takes the behavior of the item `` as it was
before **Supvisors** version 0.13, i.e. the assignment is strictly limited by the length of the `identifiers` list,
without roll-over.
NOTE: This is not available for Application rules.

* Use host aliases when looking for the local **Supvisors** instance.

* Use IP address rather than host identification when dealing with `SINGLE_NODE` starting strategy.

* To prevent the situation that led the `Starter` to block, a new state `CHECKED` is added to `SupvisorsInstanceStates`,
which is actually a pre-`RUNNING` state.
Such a **Supvisors** instance is considered active and is updated with received events but cannot be part of any
starting sequence until all starting jobs in progress are completed.

* Limit the consideration of the process forced state to display in the Application page of the **Supvisors** Web UI,
so that it does not interfere with the real process state.

* Add `master_identifier` to the output of the XML-RPCs `get_supvisors_state` and `get_instances_info`.
The `supervisorctl` commands `sstate` and `instance_status` have also been updated.

* Monkeypatch **Supervisor** on-the-fly so that its logger is thread-safe and add log traces in **Supvisors** threads.

* Simplify the **Supvisors** state machine and replace the states `RESTART` and `SHUTDOWN` by a single state `FINAL`.

* Highlight the process line hovered by the cursor in the **Supvisors** Web UI.

* Remove the figures from the **Supvisors** Web UI when `matplotlib` is not installed.

* Add RPC `changeLogLevel` to the JAVA client.

* Do not catch XmlRpc exceptions in the JAVA client.

* Refactoring of the **Supvisors** internal communications.

* Add `websockets` as an option to the **Supvisors** event listener (Python 3.7+ only).

* Re-design the `PyZMQ` event listener using the `zmq.asyncio` support for better commonalities
with the `wesockets` solution.

* Re-design the statistics collection and compilation.

* The option `stats_enabled` takes additional values to control host and process statistics independently.

* The option `stats_collecting_period` has been added to set the minimum time between process statistics collection.

* The option `stats_periods` accepts float values, not necessarily multiples of 5.

* Fix [Issue 54](https://github.com/julien6387/supvisors/issues/54).
Add host and process statistics to the **Supvisors** event interface.

* Fix children process CPU times in statistics.

* Fix Solaris mode not taken into account for the process mean CPU value in the **Supvisors** Web UI.

* Fix Flask `start_args` to pass the extra arguments in the URL attributes rather than in the route.

* Only one **Supvisors** instance is running when both `unix_http_server` and `inet_http_server` sections are defined
in the supervisor configuration file.

* The local **Supvisors** instance is identified as the item having the same fully qualified domain name
(as returned by `socket.gethostaddr` and `socket.getfqdn`) among the items of the `supvisors_list` option.

* Use the HTTP server port to help the identification of the local **Supvisors** instance when multiple items
of the `supvisors_list` option fit and identifier is not set.

* The attribute `process_failure` is added to the `get_instance_info` XML-RPC to inform if there is a process failure
in the **Supvisors** instance. The attribute is also provided in the event interface and in the `instance_status`
option of the `supervisorctl` command.

* Raise an exception when the matching **Supvisors** instance in the `supvisors_list` option is inconsistent
with the local configuration.

* Add a **Supvisors** logo.