Drupal.

[FIXED]: Error: Call to a member function transformDimensions() on null in core/modules/ image/image.module

The issue stems from the preview being in an undefined style.

1. Go to configuration -> image styles and review the styles available. I have a style called "200x200 thumb".

2. After adding an image field to a content type, go to manage form display, expand the display of the image, and specify an existing style from step 1 as the preview style.

After taking these steps, the page for adding/editing this content type should render correctly.

Default Drupal file attachment types

I have the following list of extensions that I usually permit in drupal attachments:

  txt pdf doc docx html csv xlsx xlsm sh json
  cer pem pub key
  png jpg jpeg gif
  mkv sfv avi mp3 mp4 webm mov
  zip tar gz

How to program Drupal Cron

From drupalsun.

Implementing Cron tasks in Drupal

Cron tasks are defined by implementing the hook_cron hook in your module, just like in previous Drupal versions.

/** 
 * Implements hook_cron(). 
**/ 
function example_cron() { 
  // Do something here. 
}

And that's pretty much it. Rebuild cache and next time cron runs your hook will be called and executed.

An example of a bug report and the technical conversation around it to resolve it

I recently had to justify the amount of effort that software development takes. Someone unfamiliar with the process thought that software development is easy, or that it doesnt take much time. They thought, for example, that an advanced reporting app can get pdf export capability if they just said to the development team, "implement pdf export." Literally, they thought that writing a single line of text like that in a specification document would result in the organization gaining that functionality.