add a hack to send fpm children logs to docker-captured stderr

app/Dockerfile

@@ -9,9 +9,13 @@ RUN apk add --no-cache dcron php8 php8-fpm \
 	php8-session php8-tokenizer php8-dom php8-fileinfo \
 	php8-json php8-iconv php8-pcntl php8-posix php8-zip \
 	php8-openssl git postgresql-client sudo php8-pecl-xdebug rsync && \
-	sed -i.bak 's/^listen = 127.0.0.1:9000/listen = 9000/' /etc/php8/php-fpm.d/www.conf && \
-	sed -i.bak 's/\(memory_limit =\) 128M/\1 256M/' /etc/php8/php.ini && \
-	sed -i.bak 's/;clear_env = .*/clear_env = no/i' /etc/php8/php-fpm.d/www.conf && \
+	sed -i 's/\(memory_limit =\) 128M/\1 256M/' /etc/php8/php.ini && \
+	sed -i -e 's/^listen = 127.0.0.1:9000/listen = 9000/' \
+		-e 's/;\(clear_env\) = .*/\1 = no/i' \
+		-e 's/^\(user\|group\) = .*/\1 = app/i' \
+		-e 's/;\(php_admin_value\[error_log\]\) = .*/\1 = \/tmp\/error.log/' \
+		-e 's/;\(php_admin_flag\[log_errors\]\) = .*/\1 = on/' \
+			/etc/php8/php-fpm.d/www.conf && \
 	mkdir -p /var/www ${SCRIPT_ROOT}/config.d
 
 ADD startup.sh ${SCRIPT_ROOT}

app/startup.sh

@@ -96,5 +96,8 @@ cd $DST_DIR && sudo -E -u app php8 ./update.php --update-schema=force-yes
 
 touch $DST_DIR/.app_is_ready
 
-sudo -E -u app /usr/sbin/php-fpm8 -F
+rm -f /tmp/error.log && mkfifo /tmp/error.log && chown app:app /tmp/error.log
 
+(tail -q -f /tmp/error.log >> /proc/1/fd/2) &
+
+exec /usr/sbin/php-fpm8 --nodaemonize --force-stderr