implement CiviCRM's double opt-in feature for newsletter

CRM/Twingle/Form/Profile.php

@@ -327,11 +327,19 @@ class CRM_Twingle_Form_Profile extends CRM_Core_Form {
       );
     }
 
+    $this->add(
+      'checkbox', // field type
+      'double_opt_in', // field name
+      E::ts('Use Double-Opt-In for newsletter'), // field label
+      FALSE, // is not required
+      array()
+      );
+
     $this->add(
       'select', // field type
       'newsletter_groups', // field name
       E::ts('Sign up for newsletter groups'), // field label
-      static::getNewsletterGroups(), // list of options
+      static::getNewsletterGroups($this->profile->getAttribute('double_opt_in')), // list of options
       FALSE, // is not required
       array('class' => 'crm-select2 huge', 'multiple' => 'multiple')
     );
@@ -548,6 +556,7 @@ class CRM_Twingle_Form_Profile extends CRM_Core_Form {
         $values['name'] = 'default';
       }
       $this->profile->setName($values['name']);
+      $this->profile->setAttribute('double_opt_in', isset($values['double_opt_in']));
       foreach ($this->profile->getData() as $element_name => $value) {
         if (isset($values[$element_name])) {
           $this->profile->setAttribute($element_name, $values[$element_name]);
@@ -795,11 +804,12 @@ class CRM_Twingle_Form_Profile extends CRM_Core_Form {
      * Retrieves active groups used as mailing lists within the system as options
      * for select form elements.
      *
+     * @param $double_opt_in
+     *
      * @return array
      *
-   * @throws \CiviCRM_API3_Exception
      */
-  public static function getNewsletterGroups() {
+  public static function getNewsletterGroups($double_opt_in) {
     if (!isset(static::$_newsletterGroups)) {
       static::$_newsletterGroups = array();
       $group_types = civicrm_api3('OptionValue', 'get', array(
@@ -807,7 +817,18 @@ class CRM_Twingle_Form_Profile extends CRM_Core_Form {
         'option_group_id' => 'group_type',
         'name' => CRM_Twingle_Submission::GROUP_TYPE_NEWSLETTER,
       ));
-      if ($group_types['count'] > 0) {
+        if ($group_types['count'] > 0 && $double_opt_in) {
+            $query = civicrm_api3('Group', 'get', array(
+                'is_active' => 1,
+                'group_type' => "Mailing List",
+                'option.limit'   => 0,
+                'visibility' => 'Public Pages',
+                'return'     => 'id,name'
+            ));
+            foreach ($query['values'] as $group) {
+                static::$_newsletterGroups[$group['id']] = $group['name'];
+            }
+        } elseif ($group_types['count'] > 0) {
         $group_type = reset($group_types['values']);
         $query = civicrm_api3('Group', 'get', array(
           'is_active' => 1,

CRM/Twingle/Profile.php

@@ -221,6 +221,7 @@ class CRM_Twingle_Profile {
         'membership_type_id',
         'membership_type_id_recur',
         'membership_postprocess_call',
+        'double_opt_in'
       ),
       // Add payment methods.
       array_keys(static::paymentInstruments()),
@@ -293,6 +294,7 @@ class CRM_Twingle_Profile {
       'custom_field_mapping' => NULL,
       'membership_type_id' => NULL,
       'membership_type_id_recur' => NULL,
+      'double_opt_in' => NULL,
     )
       // Add contribution status for all payment methods.
       + array_fill_keys(array_map(function($attribute) {

README.md

@@ -54,6 +54,7 @@ for all newly created Twingle projects.
 | CiviSEPA creditor                     | When enabled to integrate with CiviSEPA, specify the CiviSEPA creditor to use.                                                                                                           |
 | Gender options                        | Specify which CiviCRM gender option the incoming Twingle gender value should be mapped to. The list is based on your CiviCRM configuration.                                              |
 | Record *Payment method* as            | Specifiy the payment methods mapping for incoming donations for each Twingle payment method.                                                                                             |
+| Double opt-In                         | Let CiviCRM handle the double opt-in. Group memberships for newsletter mailing lists will be pending until receivement of double opt-in confirmataion.                                   |
 | Sign up for groups                    | Whenever the donor checked the newsletter/postal mailing/donation receipt checkbox on the Twingle form, the contact will be added to the groups listed here.                             |
 | Assign donation to campaign           | The donation will be assigned to the selected campaign. If a campaign ID is being submitted using the `campaign_id` parameter, this setting will be overridden with the submitted value. |
 | Create membership of type             | A membership of the selected type will be created for the Individual contact for incoming one-time donations. If no membership type is selected, no membership will be created.          |

api/v3/TwingleDonation/Submit.php

@@ -484,8 +484,29 @@ function civicrm_api3_twingle_donation_Submit($params) {
       $result_values['organization'] = $organisation_id;
     }
 
+      // If usage of double opt-in is selected, use MailingEventSubscribe.create to add contact to newsletter groups
+      // defined in the profile
+      $result_values['newsletter']['double_opt_in'] = ($profile->getAttribute('double_opt_in')) ? 'true' : 'false';
+      if ($profile->getAttribute('double_opt_in') &&
+          !empty($params['newsletter']) &&
+          !empty($groups = $profile->getAttribute('newsletter_groups'))) {
+          $group_memberships = array_column(civicrm_api3('GroupContact', 'get', array (
+              'sequential' => 1,
+              'contact_id' => $contact_id
+          ))['values'], 'group_id');
+          foreach ($groups as $group_id) {
+              if (!in_array($group_id, $group_memberships)) {
+                  $result_values['newsletter'][][$group_id] = civicrm_api3('MailingEventSubscribe', 'create', array(
+                      'email' => $params['user_email'],
+                      'group_id' => (int) $group_id,
+                      'contact_id' => $contact_id,
+                  ));
+              } else {
+                  $result_values['newsletter'][] = $group_id;
+              }
+          }
     // If requested, add contact to newsletter groups defined in the profile.
-    if (!empty($params['newsletter']) && !empty($groups = $profile->getAttribute('newsletter_groups'))) {
+    } elseif (!empty($params['newsletter']) && !empty($groups = $profile->getAttribute('newsletter_groups'))) {
       foreach ($groups as $group_id) {
         civicrm_api3('GroupContact', 'create', array(
           'group_id' => $group_id,

l10n/de_DE/LC_MESSAGES/twingle.po

@@ -306,3 +306,7 @@ msgstr "Profil %1 zurücksetzen"
 #: templates/CRM/Twingle/Page/Profiles.tpl
 msgid "Delete profile %1"
 msgstr "Profil % 1 löschen"
+
+#: templates/CRM/Twingle/Page/Profiles.tpl
+msgid "Use Double-Opt-In for newsletter"
+msgstr "Nutze Double-Opt-In für Newsletter"

templates/CRM/Twingle/Form/Profile.tpl

@@ -208,6 +208,11 @@
 
       <table class="form-layout-compressed">
 
+        <tr class="crm-section">
+          <td class="label">{$form.double_opt_in.label}</td>
+          <td class="content">{$form.double_opt_in.html}</td>
+        </tr>
+
         <tr class="crm-section">
           <td class="label">{$form.newsletter_groups.label}</td>
           <td class="content">{$form.newsletter_groups.html}</td>