Sending PHP application logs to AWS App Runner container application log (stdout, stderr)

I have a container running in App Runner with a PHP application on it. It has no outbound internet access nor Endpoint to log directly to CloudWatch and so want to utilise the application logs provided by App Runner.

Nginx logs are posted there which include the request details etc however every way I've tried to post the PHP application logs to it it fails:

• Logging to /proc/1/fd/1 fails due to permission issues
• Logging directly fails due to network connectivity
• Running a background task via tail -f /var/log/file > /proc/1/fd/1 & in the startup script works locally however doesn't work in App Runner and I have no logging information why.

EDIT

Also tried supervisord and tailing the log as a process:

[program:logging]
command=/bin/tail -f /app/log/file.log
stdout_logfile=/proc/1/fd/1
stdout_logfile_maxbytes=0
stderr_logfile=/proc/1/fd/1
stderr_logfile_maxbytes=0
priority=300

Once again this works on local containers but not in App Runner

Is there a way to send the logs to the App Runner Application Logs for a PHP app?

I believe you can redirect your logs to /dev/stderr as mentioned in docker's official documentation.

Sample code:

$stderr = fopen( 'php://stderr', 'w' );
fwrite($stderr, "Written through the PHP error stream" );
fclose($stderr);

This will output in the docker logs like this:

2025-04-02 09:00:27 Written through the PHP error stream
2025-04-02 09:00:27 192.168.65.1 - - [02/Apr/2025:00:00:27 +0000] "GET /log.php HTTP/1.1" 200 68 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/134.0.0.0 Safari/537.36" "-"

And based from this Q&A, I was able to verify in my sample App Runner that the application logs are being written from PHP.

For my exact setup, I'm using serversideup/php:8.3-fpm-nginx as the base image and I've placed log.php to /var/www/html/public folder. My App Runner is configured to build the app from my private ECR.

Here is the code for log.php

<?php

echo '<h1>PHP: Hello World!</h1>';
error_log('Hello World from plain PHP');

$stderr = fopen( 'php://stderr', 'w' );
fwrite($stderr, "Written through the PHP error stream" );
fclose($stderr);

?>

<h1>Hello World HTML</h1>

Here is the full Dockerfile:

FROM --platform=linux/amd64 serversideup/php:8.3-fpm-nginx

# Copy Source Code
COPY --chown=www-data . /var/www/html

RUN composer install \
    --no-dev \
    --optimize-autoloader \
    --prefer-dist && \
    php artisan optimize

Take note, I'm using the laravel framework. But when I testing the logging, I'm using public/log.php which can be accessible by http://localhost:8080/log.php

Hope this helps,

Regards