Question: How is logging handled in Craft 3? There's nothing mentioned in [the docs](https://github.com/craftcms/docs) at all.

None of the below exist.

* Craft::log()
* MyPlugin::log()
* MyPlugin::$plugin->log()

I'm not seeing any logging in any of the other plugins I've got on this site.

Halp!

Answer: 
Another perhaps simpler approach is to write to your own log file without using the Craft logger at all.

```
$file = Craft::getAlias('@storage/logs/pluginhandle.log');
$log = date('Y-m-d H:i:s').' '.$message."\n";

\craft\helpers\FileHelper::writeToFile($file, $log, ['append' => true]);

```

UPDATE: 

I released the [Log To File Helper](https://github.com/putyourlightson/craft-log-to-file) which provides a simple way for logging messages to a specific file and is intended to be used a helper class for modules and plugins.
`web.log` is incredibly verbose, I agree. I think Andrew Welch is right that you should use the Yii2 Debug Toolbar for elaborate stuff, but if you just need some one-line logs to get your bearings in a method, I'd set up the log statement like this:

`Craft::info("hello!", __METHOD__);`

That second parameter will categorize your call with the method you're calling the log function from. Then, to filter it out from all the rest of `web.log`, you can run a tail command with a filter on it. Assuming you've got a Unix shell, something like this.

`tail -f web.log | grep "YourMethodName"`

So now as you execute your commands and trigger the log statements, you'll only see those that are coming from the method you're debugging.