October CMS – How To Fix Broken Thumbnails

October CMS Logo

I recently started setting up a dockerized October CMS environment based on Alpine Linux, MariaDB and PHP-FPM which was actually a very straightforward process. However, for some reason the integrated image resizer didn’t create thumbnails of uploaded images.

October CMS - Broken Thumbnail Image

Unfortunately there was nothing in the log files which could help me to identify the cause of the problem. After checking the file permissions, I decided to trace back the issue and found the reason in file vendor/october/rain/src/Database/Attach/Resizer.php.

The method getMimeType() returned always null, which broke the entire image manipulation process.

After a quick research I found out that getMimeType requires php_fileinfo which I simply forgot to set in my Dockerfile. After adding php7-fileinfo and rebuilding the container, the issue was finally fixed.


Notice: Use of undefined constant T_CURLY_OPEN – assumed ‘T_CURLY_OPEN’ in /var/www/src/setup/src/ Magento/Setup/Module/ Di/Code/Reader/FileClassScanner.php on line 72

Today I finally had some time to cleaned up my Dockerfile for Magento 2. I am using Alpine Linux for most of my Magento 2 projects which usually includes NGINX, PHP-FPM and MariaDB.

While testing my updated Dockerfile I came across the following PHP notice which prevented the deployment scripts from finishing the Magento 2 setup.

The problem was simply a missing PHP extension php7.1-tokenizer which has resolved the issue after re-creating the container with –build.


PHP message: PHP Fatal error: Interface ‘SessionHandlerInterface’ not found in /var/www/src/vendor/ laravel/framework/src/Illuminate/Session/FileSessionHandler.php on line 10

Today I successfully installed my first October CMS project locally via composer / command line. The installation was pretty straightforward and worked surprisingly well on my Alpine Linux docker container which includes NGINXPHP-FPM and MariaDB.

However, when I tried to open the front-end I got the following error.

After a quick research I found the solution on Stackoverflow. I basically forgot to install the PHP extension php7-session inside my docker container. I manually installed the missing extension, but also updated my Dockerfile in case I have to rebuild my container.

After that I manually killed all PHP processes to make sure php-fpm loads the new extension with the next page reload.


Nginx Docker Container and getpwnam(“www-data”) problem

I am using nginx:1.10.1-alpine to run Nginx as a docker container. Today I have replaced the Nginx container and always got the status Restarting (1) Less than a second ago after starting the container.

With the command docker logs nginx I got the following error logs.

The error message basically means that the user www-data which I have defined in /etc/nginx/nginx.conf doesn’t exists in /etc/passwd. That makes sense, because nginx:1.10.1-alpine comes with a minimal setup. I my case I need the user www-data for other linked php-fpm containers. To fix the problem I just added the missing user during the container build.


Reload Nginx Inside Docker Container

I am using docker for Nginx which is running with multiple virtual hosts. Sometimes I have to reload my updated nginx configurations, but I don’t want restart the container each time. Here is how you can reload your nginx without any downtime and without interrupting any connections.

1. Find your container name

Use docker ps to find your nginx container.

2. Reload Nginx

With docker exec -it {container_name} {command} you can directly access your container and execute commands. In my case the name of the container is nginx-server.