How to get form fields in Facebook Lead Ads API?

Question

I'm using Facebook Lead Ads API. I need to retrieve all fields from a form by ID. I know I can:

• get all forms by calling /<PAGE_ID>/leadgen_forms, but it doesn't return the fields
• get a form by /<FORM_ID>, but it displays only the name and a few data, but not fields
• get all leads by /<FORM_ID>/leads - it gives me the fields in each lead, but only if I have leads; there's also another problem with this solution - the order of the fields is random

Is there any dedicated way to retrieve leadgen form fields, even when there are no leads yet?

I found out that I can download the CSV and in the first row, it gives me all fields IDs (and some other columns). I'm not sure though how I can read the content of this file in PHP, because it gives me some HTML when I try to use get_file_contents() on it.

Answer 1

You can get these by adding non-default field questions, so the url becomes /<form_id>?fields=id,name,questions.

The official docs don't describe the fields available for reading but the questions field and its nested fields are described in the params used for creating a lead form.

Example output

{
  "id": "1234567890000",
  "name": "test form",
  "questions": [
    {
      "key": "name",
      "label": "Full Name",
      "type": "FULL_NAME",
      "id": "777888999000111"
    },
    {
      "key": "email",
      "label": "Email Address",
      "type": "EMAIL",
      "id": "111222333444555"
    }
  ]
}