eck.install

<?php

/**
 * @file
 * This install file creates a table for the this module to store information
 * about entities. Well, the only information that it needs to store is a name
 * and a label for each entity created, the rest of the information is generated
 * by the functions.
 *
 * eck__entity_info
 * efacoty__entity_schema
 * eck__entity_menu
 *
 * in eck.module
 */

/**
 * TODO: Currently when the module is uninstalled, the tables of Entities that
 * were left behind are still around, can we warn the user when they are trying
 * to uninstall about the left over entities that are being managed?
 */

/**
 * Implements hook_schema().
 *
 * Create the database table that will store the entities information.
 * All that we need for each entity is a name and a label
 */
function eck_schema() {
  module_load_include('inc', 'eck', 'eck.entity_type');

  $schema = array();

  // Schema for the eck table.
  $schema['eck'] = array(
    'description' => "The base table for entities information",
    'fields' => array(
      'id' => array(
        'description' => "The primary identifier for a(n) entity",
        'type' => 'serial',
        'unsigned' => TRUE,
        'not null' => TRUE,
      ),
      'name' => array(
        'description' => "The machine name of the entity",
        'type' => 'varchar',
        'type' => 'varchar',
        'length' => 128,
        'not null' => TRUE
      ),
      'label' => array(
        'description' => "The entity's Label",
        'type' => 'varchar',
        'type' => 'varchar',
        'length' => 128,
        'not null' => TRUE
      )
    ),
    'primary key' => array('id'),
  );

  $schema['eck_types'] = array(
    'description' => "The base table for entities types information",
    'fields' => array(
      'id' => array(
        'description' => "The primary identifier for a(n) entity type",
        'type' => 'serial',
        'unsigned' => TRUE,
        'not null' => TRUE,
      ),
      'entity' => array(
        'description' => "The entity this type belongs to",
        'type' => 'varchar',
        'type' => 'varchar',
        'length' => 128,
        'not null' => TRUE
      ),
      'type' => array(
        'description' => "The type (bundle) name that will be used",
        'type' => 'varchar',
        'type' => 'varchar',
        'length' => 128,
        'not null' => TRUE
      ),
      'label' => array(
        'description' => "A human readable name for the bundle (not that the type is not human readable)",
        'type' => 'varchar',
        'type' => 'varchar',
        'length' => 128,
        'not null' => TRUE
      )
    ),
    'primary key' => array('id'),
    'indexes' => array(
      'entity_type'      => array('entity', 'type'),
    ),
  );

  // At the installation stage, eck has not been created, so what is this for?
  if (db_table_exists('eck')) {
    // When something requests an entity's info, the hook_schema is called to
    // get the information about the entity's table, so we need to provide that
    // information in the hook.

    // Get all the entities that have been create (all the rows in eck table).
    $results = db_select('eck', 'e')->fields('e', array('name', 'label'))->execute();
    foreach ($results as $result) {
      // The function entity_basic_schema defines a standard schema for each
      // entity created.
      $schema =
      array_merge($schema, array("eck_{$result->name}" => eck__entity_type__schema($result->name)));
    }
  }

  return $schema;
}

/**
 * Update 7000
 */
function eck_update_7000() {
  // To implement bundles (types), I have decided to have one table that will
  // hold all of the types information. So for this update we need to create the
  // table, and add all of the current entities with their types to the table,
  // so we can unify the implementations of bundles in code.

  $schema = array(
    'description' => "The base table for entities types information",
    'fields' => array(
      'id' => array(
        'description' => "The primary identifier for a(n) entity type",
        'type' => 'serial',
        'unsigned' => TRUE,
        'not null' => TRUE,
      ),
      'entity' => array(
        'description' => "The entity this type belongs to",
        'type' => 'varchar',
        'type' => 'varchar',
        'length' => 128,
        'not null' => TRUE
      ),
      'type' => array(
        'description' => "The type (bundle) name that will be used",
        'type' => 'varchar',
        'type' => 'varchar',
        'length' => 128,
        'not null' => TRUE
      ),
      'label' => array(
        'description' => "A human readable name for the bundle (not that the type is not human readable)",
        'type' => 'varchar',
        'type' => 'varchar',
        'length' => 128,
        'not null' => TRUE
      )
    ),
    'primary key' => array('id'),
    'indexes' => array(
      'entity_type'      => array('entity', 'type'),
    ),
  );

  db_create_table('eck_types', $schema);

  // Now we add a type (bundle) to the table for each entity in the eck table.

  $results = db_select('eck', 't')->fields('t')->execute();

  foreach ($results as $record) {
    $nid = db_insert('eck_types')
    ->fields(array(
        'entity' => $record->name,
        'type' => $record->name,
        'label' => $record->label,
    ))
    ->execute();

    // Also we want to add a field to all the enity tables for the type, and
    // populated with the current type.
    db_add_field("eck_{$record->name}", 'type', array(
      'description' => 'The type of the entity',
      'type' => 'varchar',
      'default' => '',
      'length' => 255,
      'not null' => TRUE,
      'initial' => $record->name
    ));

  }
}

/**
 * Update 7001
 */
function eck_update_7001() {
  // For importing and exporting things it is always good to have a uuid, so we
  // will add that colunm to the current entity types.

  // Now we add a type (bundle) to the table for each entity in the eck table.

  $results = db_select('eck', 't')->fields('t')->execute();

  foreach ($results as $record) {
    // Also we want to add a field to all the enity tables for the type, and
    // populated with the current type.
    db_add_field("eck_{$record->name}", 'uuid', array(
      'type' => 'char',
      'length' => 36,
      'not null' => TRUE,
      'default' => '',
      'description' => 'The Universally Unique Identifier.'
    ));

  }
}

function eck_update_7002() {
  // The more I think about it, the more it makes sense to replicate the
  // "status" property from nodes, this is just a flag that lets the system know
  // whether a piece of data should be seen by the public or not. Instead of a
  // boolean, I think that a int instead of boolean could be more useful, that
  // way more complicated workflows can be implemented. For example if a piece
  // of data needs to be reviewed before showing it to the public, and int can
  // campture those different states: 0- don't show 1 - show 3 - needs review 4
  // - revised by editor, etc. Also instead of status, I think that "state" is a
  // more appropiate name.

  $results = db_select('eck', 't')->fields('t')->execute();

  foreach ($results as $record) {
    db_add_field("eck_{$record->name}", 'state', array(
     'type' => 'int',
     'unsigned' => TRUE,
     'not null' => TRUE,
     'default' => 0,
     'description' => 'The state of the entity'
    ));
  }
}