Do Not Use Exception Class Directly

Do not throw Exception

There are a lot of specific Exception descendants in PHP. See documentation for the full list. It's not necessary to use and remember all of them, many have unclear use cases, but at very least you should separate your exceptions into RuntimeException and LogicException. As the doc says, LogicException means code misuse. Throw LogicException in cases when the upstream must be fixed because it uses your code incorrectly. Throw RuntimeException in cases that are not predictable by the upstream, like service failures or invalid user input.

In case you use exceptions for flow control, you need your own custom exceptions anyway. In this case you can extend the base Exception, extending Exception directly is not a sin, especially if your exceptions are not error conditions.

Do not catch Exception

Assuming you follow the previous point, there is no need to catch Exception's.

1. If you don't guard against a specific situation, catch all RuntimeException's. LogicException's should go to your logger.

2. In a global error handler that writes your logs, you need to catch Errors too, so you need to go even further and catch Throwable.

3. If you use exceptions for flow control (please don't haha) you already catching your own exceptions, and if you follow the previous point, they are already separated from actual error conditions and won't be caught mistakenly by a wrong level.

Notable exceptions to the rule:

• You use PHP below 7.0 and don't have Throwable. Well, it's 2024 already so this is another call for you to upgrade. Otherwise assume point 2 allows you to catch a base Exception.

• You use a library that throws plain Exception instances. Well, bad for you, but maybe it's a good idea to report this thing as a problem.