think like a drupal developer

Drupalcamp Atlanta 2011

Think Like a Drupal Developer

Erik WebbTechnical Consultant, Acquia



Who am I?

• Joined Acquia in April 2010

• 30+ clients in almost 2 dozen states

• Systems administrator background (RHCE)

• LAMP development (10+ years PHP)

• Go Jackets!


Who are you?


Drupal is hard. It's not just a CMS, it's not just a framework, it has the power of both and the simplicity of neither. So where do you get started?


How Drupal works

1. Lookup URL in aliases, menu router

2. Check for cached page

3. Check permissions for page

4. Run page callback

5. Process render array


What Drupal Can Do

• Managing lots of structured data

• Strictly manage access to content and functionality

• Providing an organized administration section

• Allowing themers great flexibility

• Using common page layouts


Coders vs. Builders

• We’re all developers

• Good Drupal developers are “lazy”• Efficiency beats all

• Enjoy your weekends!

• Trust the community

• Rethink problems, not solutions


Building vs. Coding

• Building• Flatter learning curve

• Easier transition for “web developers”

• More maintainable*

• Dependent on community

• Book learnin’

• Faster development

• Reusable solutions

• Coding• Steep learning curve

• Easier transition for programmers

• Less maintainable*

• Customized to client

• Blood, sweat, & tears

• Faster performance*

• One-off advantages


What to code


Modifying Forms

• hook_form_alter(), hook_form_FORM_ID_alter()

• Administrative and user-facing forms

• Examples• Making individual fields required

• Changing order of fields

• Adding help text

• Additional validation or submission handlers


Changing Nodes

• Structure• hook_node_view()

• Add new data

• Modify existing data

• Change data in all places

• Presentation• template_preprocess_nod

e()

• Reformat data

• Combine into pseudo-fields

• NEVER alter data, treat as read-only


Menu Manipulation

• hook_menu_alter()

• Change menu properties• Hide links globally

• Change title

• Change permissions

• Override callbacks

• Efficient, runs only on cache clear


When to code or build


Content Aggregation

• Views• Graphical setup

• Community-driven

• Built-in caching

• Many display options

• Efficient prototyping

• EntityFieldQuery• Full control*

• Low overhead

• Extremely Drupal-specific

• No SQL!

• Combine with Entity Load Cache*


Contextual Changes

• Context module• Flexible API

• Easily exportable to code

• Extendable by non-coders

• hook_boot(), hook_init()

• Completely custom

• Performance-focused

• Handling condition and reactions


Examples


Client: Anytime an anonymous user visits a news article, I want to show them a modal with a subscription link.


Use Context

• Wrong way• template_preprocess_node() to add JS in a theme

• Right way• Create a modal reaction for Context

• Why not use hook_boot()?

• Right way• Use pure JavaScript to check for body.logged-in CSS class


Client: I don’t want anonymous users seeing any content tagged with the “Internal” keyword.


Nodes are everywhere!

• Wrong way• hook_node_access() doesn’t affect the menu

• Wrong way• Override ‘access callback’ for URL ‘node/%’

• Wrong way• hook_node_view() returns drupal_access_denied()

• Right way• hook_node_access_records() changes all node accessing


Client: I want all checkboxes to be those cool image buttons instead of the normal checks.


Form altering isn’t always the right way

• Wrong way• Use CSS/JS to change input[type=”checkbox”]

• Wrong way• Use hook_form_alter() to change the ‘#theme’ property for

all checkboxes to your theme function

• Right way• Simply create modulename_checkbox() to override all uses

of the form element


Client: I want to incorporate my company-‐wide header/masthead into my Drupal site.


iframe? What is this, 1999?

• Wrong way• Hard code into an include file in your theme

• Wrong way• Recreate the header using Drupal’s menu system and CSS

• Right way• Create a JS include somewhere else

• Right way• Use a web service to retrieve the HTML (and cache it!)


Questions?

Ask me - @erikwebb on Twitter

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