Redirect only after inserting a new node?

Question

I had a rule of 'After saving new content' of type, redirect to url. I need to add second submit button to the content type so I decided to add the redirect to a custom module so I can have different actions depending on the button. The redirect works on the submit button but I only want this to happen when adding/inserting a new node. Right now it redirects every time the submit button is clicked.

In mymodule_form_alter:

$form['actions']['submit']['#submit'][] = 'submission_form_submit';

Then:

function mymodule_form_submit($form, &$form_state) {  
  $form_state['redirect'] = 'info-received';
}

Code suggestions needed. But if there is a way to have rules perform different actions based on which button is clicked I can use that advice also.

ETA: the code used for the second button

$form['actions']['submit_another'] = array(
  '#type' => 'submit',
  '#name' => 'save_another',
  '#value' => t('Save, and Add Another.'),
  '#submit' => array('node_form_submit','submission_form_create_duplicate_form_submit'),
  '#weight' => 40,  
);

ETA2: Trying is_new

function mymodule_form_submit($form, &$form_state) {  
  $node = $form_state['node'];

  if(isset($node->type) && $node->type == 'submission') {
    dsm('Reached Node Type Check!'); // <- this works

    if (isset($node->is_new)) {
    dsm('Reached New Node Check!'); // <- this does not work
    $form_state['redirect'] = 'info-received';
    }
  } 
}

Changed the if statement checking for new node to

if ($node->is_new) {    

Results in 'Notice: Undefined property: stdClass::$is_new in mymodule_form_submit()'

It seems the value for is_new is not set.

Answer 1

You could use hook_node_insert() under this hook should use drupal_goto() for redirect. The hook_node_insert() only trigger when a new node inserted. If you also want to update. You could use hook_node_update().

Answer 2

In your $form or in your $form_state, you have the node object, in which you can check if it's a new node by the key is_new, the value being a boolean.

You can base a condition for the redirection on this.