Uncaught Emitter Exception (Output has been previously emitted)

[filisko]

Hi, I get this error right after I start my docker setup (I can repeat it as many times as I want by restarting), when I remove the middleware I don't get any error.

Any ideas? I'm using lamina's emitter.

[filisko]

Update.

I installed middlewares/emitter and the problem became clearer. It seems that Lamina's exception is due to a PHP Deprecation notice. So basically, Lamina's Emitter detected this as "Output previously emitted"... kinda makes sense but kinda not :)

I'll upload a fix to the repo ASAP.

This makes me think though: is Lamina's behaviour valid and middlewares/emitter not, or the other way round :) ? @oscarotero

Personally, I'm happy that I figured out what happened thanks to the current behaviour of middlewares/emitter :)

If I had done this, I would have caught it before:

ini_set('display_errors', '1');
ini_set('display_startup_errors', '1');
ini_set('error_log', __DIR__.'/errors.log');
ini_set('log_errors', '1');
error_reporting(E_ALL);

[15-Mar-2025 13:13:39 Europe/Madrid] PHP Deprecated:  Middlewares\Whoops::__construct(): Implicitly marking parameter $whoops as nullable is deprecated, the explicit nullable type must be used instead in /var/www/html/vendor/middlewares/whoops/src/Whoops.php on line 44
[15-Mar-2025 13:13:39 Europe/Madrid] PHP Deprecated:  Middlewares\Whoops::__construct(): Implicitly marking parameter $responseFactory as nullable is deprecated, the explicit nullable type must be used instead in /var/www/html/vendor/middlewares/whoops/src/Whoops.php on line 44
[15-Mar-2025 13:13:39 Europe/Madrid] PHP Fatal error:  Uncaught Laminas\HttpHandlerRunner\Exception\EmitterException: Output has been emitted previously; cannot emit response in /var/www/html/vendor/laminas/laminas-httphandlerrunner/src/Exception/EmitterException.php:20
Stack trace:
#0 /var/www/html/vendor/laminas/laminas-httphandlerrunner/src/Emitter/SapiEmitterTrait.php(42): Laminas\HttpHandlerRunner\Exception\EmitterException::forOutputSent()
#1 /var/www/html/vendor/laminas/laminas-httphandlerrunner/src/Emitter/SapiEmitter.php(21): Laminas\HttpHandlerRunner\Emitter\SapiEmitter->assertNoPreviousOutput()
#2 /var/www/html/public/index.php(134): Laminas\HttpHandlerRunner\Emitter\SapiEmitter->emit()
#3 {main}
  thrown in /var/www/html/vendor/laminas/laminas-httphandlerrunner/src/Exception/EmitterException.php on line 20
(bas

Running PHP 8.4

[oscarotero]

I see. Unfortunately, I can't have php 8.4 in my computer (I'm using PHP 7.4, it's a long story).

Many packages in this middlewares organization were updated to avoid deprecation warnings from PHP 8.4 thanks to PRs from the community (last one).

You're welcome to fix this package and remove the warning.
Thanks!

[filisko]

Closed by #14