Lorna Mitchell has a quick post today showing how you can use the popular Monolog logging library to log messages and data to stdout, the standard output stream of whatever is executing the script.
My worker scripts have really basic logging (as in, they echo when something happens, and I can see those in the supervisord logs). Which is kind of okay, but I wanted to at least add timestamps in to them, and maybe send emails when something REALLY bad happened. I'm a huge fan of Monolog so I grabbed that, but it wasn't immediately obvious which of the many and varied options I would need for this fairly simple addition. It turns out that the right thing to use is the ErrorLogHandler.
She includes a few lines of sample code that use the "ErrorLogger" to output the message. It includes the log level, a timestamp, the message itself and any additional contextual information you pass in.