Pull Request for Issue # .

Summary of Changes

This adds a defer option to the formatted_text logger. The option is not enabled by default so the logger will continue to function in the usual way unless specifically configured.

The normal way for this logger to function is to format each received log entry as a line of text and write it to a file as it is received.

When using the defer option, received log entries will just be stored in an array when received. It will not be until the logger is destroyed (basically this happens in the shutdown process, so after the response has been sent) that the stored entries are formatted as lines of text and all written to the log file at once. This may be better for performance since multiple write operations are combined as one and (more importantly) not performed until the response has already been sent.

There is a small caveat which should be considered when deciding whether or not to use the defer option. If php encounters a fatal error, the class' __destruct function may never be called and all unwritten logs will be lost. If you are writing logs to help you determine why your fatal errors are happening, this option is not for you.

Testing Instructions

Configure a formatted_text logger and include 'defer' => true in its options array. A simple way to do this is to use the logging features of the Debug plugin. There are two formatted_text loggers already configured in that plugin (must be activated in the plugin settings) so you only need to make a minor modification to their options arrays.

Documentation Changes Required

If there is some documentation about using the formatted_text logger, it should be updated to include this option. If there isn't any, there probably should be.

Discuss?
I'm using the class __destruct function to trigger the writing of deferred logs. It's pretty convenient and it works because we can rely on the logger instance not being destroyed until the program shuts down. However, it's possible that register_shutdown_function is a better choice. I haven't tested it or even thought about it much so, if anyone has any thoughts about it, please let me know.