Read information from CiviCRM step

Fill the following fields

- REST URL= (something like http://your-host-name-here/civicrm/sites/all/modules/civicrm/extern/rest.php),
- Site key
- API key.

Remember if your server supports the use of https instead of the use of http fill the REST URL with https protocol.

Then by clicking “Get entity list” the list of entity types will be filled with all the possible entities in your CiviCRM instance.
An entity, in case you don't know it, can be everything in CiviCRM: a contact, an activity, an event or a contribution, for instance.
Select “Contact” as Entity Type and add the fields id and email, then click Ok.
You can preview the results, clicking the CiviCRM input icon with the right button.