With the Bugsnag exception handlers enabled, errors aren't output to the browser window (see #41)
The current method of disabling the Bugsnag requires using a bugsnag_set_error_and_exception_handlers filter but, because we want to initialise Bugsnag ASAP, this filter runs before a theme's functions.php file. This makes it less then ideal as you need to edit the core functions.php file in order to disable the exception handlers
This PR adds a nicer way to control whether the exception handlers are set by using a constant, which can be defined in wp-config.php — BUGSNAG_SET_EXCEPTION_HANDLERS. If this is set to true then the PHP exception and error handlers will be set
It's important to note that we will still report errors with BUGSNAG_SET_EXCEPTION_HANDLERS set to false. However this is done using a PHP shutdown function, which means we have less context about any errors that may occur — for example, we don't currently display an exception backtrace in the shutdown function, because at that point it's been converted to a PHP Fatal Error
I've kept the filter around for BC reasons, but it will now filter the constant's value if defined. If it's not defined then the current default of true will be filtered (i.e. nothing has changed if the constant is not defined)
Changeset
Tests
This was tested manually by defining a BUGSNAG_SET_EXCEPTION_HANDLERS constant with a value of true or false in wp-config.php:
If the constant isn't set (or is set to true) the exception handlers should be enabled
Discussion
Alternative Approaches
Outstanding Questions
The interaction between the new constant and the existing filter is perhaps unintuitive. I think this is the clearest option that also preserves BC, but there are others, such as using the constant if it's defined and otherwise falling back to the filter
We could also drop the filter entirely, but we can't tell how many people are currently using it
Goal
With the Bugsnag exception handlers enabled, errors aren't output to the browser window (see #41)
The current method of disabling the Bugsnag requires using a
bugsnag_set_error_and_exception_handlersfilter but, because we want to initialise Bugsnag ASAP, this filter runs before a theme'sfunctions.phpfile. This makes it less then ideal as you need to edit the corefunctions.phpfile in order to disable the exception handlersThis PR adds a nicer way to control whether the exception handlers are set by using a constant, which can be defined in
wp-config.php—BUGSNAG_SET_EXCEPTION_HANDLERS. If this is set totruethen the PHP exception and error handlers will be setIt's important to note that we will still report errors with
BUGSNAG_SET_EXCEPTION_HANDLERSset tofalse. However this is done using a PHP shutdown function, which means we have less context about any errors that may occur — for example, we don't currently display an exception backtrace in the shutdown function, because at that point it's been converted to a PHP Fatal ErrorI've kept the filter around for BC reasons, but it will now filter the constant's value if defined. If it's not defined then the current default of
truewill be filtered (i.e. nothing has changed if the constant is not defined)Changeset
Tests
This was tested manually by defining a
BUGSNAG_SET_EXCEPTION_HANDLERSconstant with a value oftrueorfalseinwp-config.php:If the constant isn't set (or is set to
true) the exception handlers should be enabledDiscussion
Alternative Approaches
Outstanding Questions
The interaction between the new constant and the existing filter is perhaps unintuitive. I think this is the clearest option that also preserves BC, but there are others, such as using the constant if it's defined and otherwise falling back to the filter
We could also drop the filter entirely, but we can't tell how many people are currently using it
Linked issues
Related to #41 and #44
Review
The constant was added in https://github.com/bugsnag/bugsnag-wordpress/commit/7cd7086a023637589bdd86a81189cce1080d60be, the rest of the changes are fixes for StyleCI
For the submitter, initial self-review:
For the pull request reviewer(s), this changeset has been reviewed for: