Changing CAE configuration

General

The exact behaviour of CAE is controlled by a configuration file named CinnamonAsynchronousEngine.config.xml that resides in the CAE program folder, typically, but not necessarily on the Cinnamon server. The configuration file is loaded when CAE is started. In the configuration file, all plugins that are used are referenced and configured.

Each plugin reference in the configuration addresses a certain plugin class in one of the assemblies (.net / mono libraries). All assemblies that are referenced in the configuration must be present in the program folder, otherwise CAE will fail initializing the plugin.

CAE and all standard plugins are compatible with .net and mono, and can run on Linux or Windows (and probably iOS - untested).

NOTE: Plugins other than the standard ones might be restricted to not run on all platforms, for example, because there is a dependency not available on one of the platforms.

Running CAE

On the server running CAE, the configuration is typically such that CAE is started on system boot. This is also the default configuration when running CAE on the Cinnamon Server according to the installation instructions.

CAE is built in a way that it is very robust against crashing plugins. Typically, CAE will log the issue and continue. However, in some rare cases, or due to causes external to CAE, CAE may cease functioning. To make sure it remains available, the standard installation uses supervise contained in the daemontools package on Debian systems. supervise watches a process, in this case CAE, and restarts it when it stops.

To run supervise to watch CAE, execute the following command:

supervise /opt/cae/bin &

The ampersand (&) character at the end of the command line instructs Linux to run the command in the background. Even if CAE logs to the shell, you can close the session and CAE will continue running.

Reloading the configuration file

Since the configuration file gets loaded on CAE start, reloading the file can be achieved by restarting CAE. This is also valid if CAE should be restarted after the executable or the libraries have changed.

Since CAE is watched by supervise which restarts CAE if it stops, CAE can be restarted by stopping it - supervise will then restart it automatically. To find the CAE process, use the following command on a Linux server:

ps aux | grep mono

This will return a result similar to the following:

The value in the red box is the process id. Stop CAE with the following command, using the process id you retrieved:

kill <process id>

Using the command

ps aux | grep mono

again will show you whether supervise has successfully restarted CAE.

Stopping CAE

You might want to stop CAE for one of the following reasons:

• To start it by hand with active console logging and debug any unwanted behaviour CAE has shown in unattended mode.
• To run CAE in the debugger on a development system.

In both cases, you must stop the supervised CAE on the server to avoid interference with your second instance of the program.

Stopping CAE works similarly as restarting CAE. Using the kill command on the CAE process stopped it and caused supervise to restart it. To stop CAE, therefore, first supervise must be stopped.

Use the following commands to retrieve the process ids for supervise and CAE. Then use the following commands:

ps aux | grep supervise
kill <supervise process id>
ps aux | grep mono
kill <mono process id>

Running CAE with immediate log output

To debug unwanted behaviour, it is useful to enable console logging and running CAE from the command line.

• Stop supervise and CAE as described above.
• Edit /opt/cae/bin/CinnamonAsynchronousEngine.config.xml with your preferred editor.
• In the log element at the beginning of the file, make sure the attribute enableconsole is set to true. Save the file if you have changed it.
• Execute the following command:

  /opt/cae/bin/cae.sh
  

NOTE: To end CAE in this mode, press Ctrl+c

ATTENTION: Make sure to set the attribute enableconsole back to false after debugging. Many Linux system do not support console output by unattended applications and cause CAE to fail. If you need a log, switch enablefile is set to true and specify a writable log path. The default log path is /opt/cae/log.

ATTENTION: Typically, you should start supervise with CAE again after debugging.