DX: Implement hook_block_* (insert/update/prepare/delete) functionality for modules

Solved this in the following way. Maybe someone else search for hook_blockapi and may find this helpful...

function MYMODULE_form_alter(&$form, &$form_state, $form_id) {
  switch ($form_id) {
    // Catch the block add/configure form and add custom submit handler.
    case 'block_add_block_form':
      // Add custom submit handler to block add form.
      $form['#submit'][] = 'MYMODULE_add_form_submit';
      break;

    case 'block_admin_configure':
      // Add custom submit handler to block configuration form.
      $form['#submit'][] = 'MYMODULE_configure_form_submit';
      break;

    case 'block_admin_display_form':
      // Add submit handler into admin/build/block for e.g. to catch "status"
      $form['#submit'][] = 'MYMODULE_admin_display_form_submit';
      break;

    default:
      break;
  }
}

function MYMODULE_add_form_submit($form, &$form_state) {
  // Get last inserted block id.
  $bid = db_last_insert_id('boxes', 'bid');
  // Execute your functions.
  _MYMODULE_foo($form_state['values'], $bid);
}

function MYMODULE_configure_form_submit($form, &$form_state) {
  // $form_state['values']['delta'] is the block id.
  // Execute your functions.
}

function MYMODULE_admin_display_form_submit($form, &$form_state) {
  // Execute your functions.
}

Mayor problem with above code is that $bid = db_last_insert_id('boxes', 'bid'); returns wrong values. See #369520: db_last_insert_id returns watchdog (wid) if comment (cid) is selected

This feature is to sync the not existing api with node and comment hooks. Form alter with submit hook cannot solve the problems for sure as you cannot be sure what bid you get. It could we a wrong bid and only the hook can provide the correct auto increment value to other modules for sure.

See linkchecker module...example in #1 is not 100% up to date... And the workaround i used IS NOT reliable.

Andypost: no. You have no chance to reliable get the correct bid. You may need to dig deeper or try to implement a blocks module that fire on block save as one example. If you compare to node orcomment api you may get the reasons why the current solutions are nothing else like unreliable buggy hacks.

Aha... Maybe something have changed in D7 I have not seen yet. But how does my module hook in here? I do not see that other modules are called before the block is saved (hook_prepare), after the block is saved (hook_insert) and what will happen on update or delete and how my module is hooked to delete other data from myblock module tables... Obove line looks like aform helper, but not like an api implementation that is working like the node api.

This is the bad way used in D6 + I really hope we can get rid of workarounds like below. They are really bad. Additional it's more worse that there is a need to have two different logics to hook into block forms. Linkchecker need to hook into custom and normal blocks.

I'm for cleaning up this workarounds and make the DX and API much cleaner and better - nevertheless it may work - it's much more complex and unreliable than the node and comment hooks that are really easy to understand.

function linkchecker_form_alter(&$form, $form_state, $form_id) {
  switch ($form_id) {
    // Catch the block add/configure form and add custom submit handler.
    case 'block_add_block_form':
      // Add custom submit handler to block add form.
      $form['#submit'][] = 'linkchecker_block_add_form_submit';
      break;

    case 'block_admin_configure':
      // Add custom submit handler to block configuration form.
      $form['#submit'][] = 'linkchecker_block_configure_form_submit';
      break;

    case 'block_box_delete':
      $form['#submit'][] = 'linkchecker_block_box_delete_form_submit';
      break;
  }
}


/**
 * Custom submit handler for block add page.
 */
function linkchecker_block_add_form_submit($form, &$form_state) {
  // UNRELIABLE WORKAROUND to get the $bid of the last added block.
  $bid = db_result(db_query("SELECT MAX(bid) FROM {boxes}"));
  _linkchecker_add_box_links($form_state['values'], $bid);
}

/**
 * Custom submit handler for block configure page.
 */
function linkchecker_block_configure_form_submit($form, &$form_state) {
  _linkchecker_add_box_links($form_state['values'], $form_state['values']['delta']);
}

/**
 * Custom submit handler for block delete page.
 */
function linkchecker_block_box_delete_form_submit($form, &$form_state) {
  _linkchecker_delete_box_links($form_state['values']['bid']);
}

As said i need hook_block_*: insert, delete, update. There is nothing fixed here. Still open.

Why is this so difficult to understand? Please try to read the public API documentation at these links. While you are reading, replace the words "hook_node_*" with "hook_block_*" and "node" with "block":
http://api.drupal.org/api/function/hook_node_insert/7
http://api.drupal.org/api/function/hook_node_delete/7
http://api.drupal.org/api/function/hook_node_update/7

Example results:
http://api.drupal.org/api/function/hook_block_insert/8

Respond to creation of a new block.

This hook is invoked from block_save() after the block is inserted into the block table in the database, after the type-specific hook_insert() is invoked, and after field_attach_insert() is called.

http://api.drupal.org/api/function/hook_block_delete/8

Respond to block deletion.

This hook is invoked from block_delete_multiple() after the block has been removed from the block table in the database, after the type-specific hook_delete() has been invoked, and before field_attach_delete() is called.

http://api.drupal.org/api/function/hook_block_update/8

Respond to updates to a block.

This hook is invoked from block_save() after the block is updated in the block table in the database, after the type-specific hook_update() is invoked, and after field_attach_update() is called.

You may get the idea. Moving to D8 as API changes need to wait for the next major version.