• Info file demo.info
• Module file demo.module

name = demo
description = Just a simple demo module
core = 7.x

// Hooking in to nodeapi
function demo_nodeapi(&$node, $op_) {
  global $user;
  if ($op == 'view') {
    if ($node->uid == $user->uid {
      $node->title . ' [YOUR ARTICLE]';
    }
  }
}

• Anytime someone says hook_something you replace hook with your module name
• You might also involve an install file
  • Where you hold logic that only runs during install or update

function tricky_install() {
  drupal_set_message('You just installed Tricky!');
}

• The .htaccess file routes all requests through index.php
  • index.php send the request through a bootstrap process and then looks for a menu.inc
• Your module can implement menu and then provide urls
  • function mymodule_menu()
  • return "Some text!" would just render some text to the screen
• Based on the request from the browser and what Drupal found it generates the best match
  • Is welcome.html an alias?
  • Is it a path?
  • Essentially use hook_menu to map paths to functions
  • The menu system is the router

• The hook system is an event listener pattern that utilizes specially named functions
• Create hooks with module_invoke_all('foo')
  • Ask all modules if they implement foo and then invoke it
  • yourmodule_foo() would use it
  • Namespace your hook with you module name to prevent collisions
• Hook Node View Examples

// Appends [YOUR ARTICLE] to the node title if the logged in user is the owner of the node
function demo_node_view($node, $view_node, $language) {
  global $user;
  if ($node->uid == $user->uid) {
    $node->title . ' [YOUR ARTICLE]';
  }
}

• The order of hooks getting called is based on weight and alphabetical order
• Objects are implictely passed by reference in PHP 5.2+ which is what Drupal 7 uses
• PHP tip: var .= ' TEXT' will concatenate and update the var

• Load in to d7/sites/all/modules/captain
  • Don’t load in to the d7/modules folder as it is for core only
• Enable through Module tab in Drupal UI
• t is a Drupal Core function for translating user facing text
  • t can also take placeholders so the strings can be dynamic
  • t runs text through check_plain which does some string escaping for security
• Nodes have url’s and Blocks do not
  • Nodes are primary content
  • Blocks are secondary content
    • They can contain content
    • They can be placed on many nodes
• $view_mode is the context in which a piece of content is being viewed
  • Viewing a full page vs a list or RSS feed
• $_SESSION is a super global for storing stuff related to session
• devel Module provides a number of functions for development
  • dsm or dpm will print out in a nicely formatted way the object
• A good tip is to prefix all data being added with your module name for debugging
• $account is the user viewing the page
• $user is the logged in user
• global pulls in a global variable to be used locally
• user_load will load a user object from the database

• Info files only require
  • name
  • description
  • core
• Info files can list dependencies with dependencies
• menu_magic_menu
  • The key ‘magic’ is the page path
  • The page callback is the function that will be called
  • The access callback is the function called when someone tries to view a page (permissions)
  • The file defines the file to include, a performance optimization
  • The type MENU_LOCAL_TASK is for the tabs at the top of a node
• Advanced Feature – 'user/%user/magic'
  • Drupal automatically calls user_load($wildcard) based on the special loader %user
  • You can also use %node and %file
  • It looks for a user_load or node_load or any function you define hooked to load
• Debug Tool – dsm(func_get_args())
  • Prints out the arguments passed to the function

• DB:TNG is a wrapper around PDO
• Static queries take an associative array of the values to sub in to the query
• Awesome Select Queries
  • Build an object up using function calls
  • $select = db_select('node', 'n')->fields('n', array('nid'))->condition('promote', 1)->orderBy('sticky', 'DESC')->execute();
  • hook_query_alter can be used by modules to alter the built up query object
  • Calling execute() is what returns results
  • addTag is used to add tags that core looks for when querying
• More Queries
  • db_insert
  • db_update
  • db_deleted

• Drupal 7 Database API
• Converting d6 queries to d7 SQL Tool
• Nodes have full and teaser $view_mode
• After you ->execute() you can call ->fetch() for one result or ->fetchAll() for all matches
• Merge Queries db_merge are the equivalent of insert or update

• Write forms in Drupal, not static HTML
• In the $form[] array any key that does start with a # is a form element
• drupal_map_assoc will turn an array of string in to an associative array with the string as the key and value
  • Caveat if you t() the values of the array in a drupal_map_assoc the keys would be translated also, which is likely wrong
• You can use form_name_form_validate to setup server side validations
• You can use form_name_form_submit to specify what happens when the form is going to be saved after validation
• Use hook_element_info to create a new type and then you could write validations that could always execute as a preprocess
• Use hook_form_alter to alter forms before they are displayed to the screen
  • You could use hook_form_alter to add a validator to user signup form that requires a long password
• The name of the function that defines the form is the form_id
• You can hook_form_id_alter to limit the scope of the hook to the specific form