Hook into Web-Form POST to send another POST request to 3rd Party Server?

Question

The site I am working on has multiple Contact us type forms that are using a web-form plugin. They have a contact form that is on every page, 1 to 2 times per page. This contact form saves to the back-end and database when submitted.

Below is the basic form without the form elements.

<form action="/" accept-charset="UTF-8" method="post" id="webform-client-form-9" class="webform-client-form" enctype="multipart/form-data" _lpchecked="1">
  <input type="hidden" name="Provider" value="YourLeadSource">
  <input type="hidden" name="Client" value="L360">
  Fname: <input type="text"  name="fname" value="John"><br />
</form>

Now I have been tasked with keeping the current functionality, posting and saving to the database, but also adding new functionality to make it also POST or GET the same form submission to a third party site called leads360.

I need to have it also send a POST or GET request with the form data to https://secure.leads360.com/Import.aspx?Provider=TeledirectBusinessName&Client=CompanyName&CampaignId=12345.

In theory this should be really easy, if I can hook into the system and send a POST or even a GET request to that URL which will then post data into the third-party system.

The problem is my limited knowledge of Drupal. I know its plugin/hook system is nothing like WordPress or Magento.

Would you use some sort of hook in the backend, or intercept the post with JavaScript the way the Stripe API does for payments?

Answer 1

There's the Webform Remote Post module that does exactly this.

Answer 2

Yes you'd use a hook in the backend, in a custom module. Just to confuse things a little bit more, the type of hook you need to implement (an 'alter' hook) can also be implemented in a custom theme. But I'd advise sticking with the custom module for this, as the functionality you need is beyond what a theme should really be responsible for.

For the low down on Drupal hooks in general, see What is the basic concept behind hooks?.

In your specific case hook_form_alter() will do the trick; as the name suggests it's used to alter a form. There's even a more specific version, hook_form_FORM_ID_alter(), which lets you alter a form with a specific ID.

To run custom code on form submission, you need to add a submit handler to the form like in the following example:

function MYMODULE_form_webform_client_form_9_alter(&$form, &$form_state, $form_id) {
  $form['#submit'][] = 'MYMODULE_send_3rd_party_data';
}

The handler is just the name of a standard PHP function that you'll write, by convention prefixed with the name of your module. When the form is submitted, the function will run. In that function, you'll need to inspect the $form_state['values]` array, which contains the user-submitted values from the form.

function MYMODULE_send_3rd_party_data($form, &$form_state) {
  // Examples...
  $name = $form_state['values']['name'];
  $age = $form_state['values']['age'];
}

From there it's just a matter of submitting the data to the 3rd party service with the method of your choice. cURL is an obvious option, but Drupal also provides the drupal_http_request() function if you'd prefer to stay within the API.