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: 
You can use `Craft::getLogger()->log($message, $level, $category = 'application')`

It uses the [Yii2 logger](http://www.yiiframework.com/doc-2.0/yii-log-logger.html), you can change the `$category` to your plugin handle

Edit: You can use the "short" syntax as well [class reference](https://docs.craftcms.com/api/v3/craft.html)

```
Craft::warning($message, $category);

```

or 

```
Craft::info($message, $category);

```
`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.