Add settings for API key and error handling.

contact-form-7-email-validator.php

+<?php
 /*
 Plugin Name: Contact Form 7 Email Validator
 Plugin URI: https://wordpress.org/plugins/contact-form-7-email-validator
@@ -8,23 +9,200 @@ Author URI: https://ant.sr
 License: MIT
 */
 
+define('API_LINK', '<a href="https://mailboxlayer.com" target="_blank">mailboxlayer</a>');
+define('API_KEY_LINK', '<a href="https://mailboxlayer.com/documentation#access_keys" target="_blank">mailboxlayer API key</a>');
+
 add_filter('wpcf7_validate_email*', 'wpcf7ev_validate_email', 20, 2);
 
 function wpcf7ev_validate_email($result, $tag) {
     $tag = new WPCF7_FormTag($tag);
     $email = isset($_POST[$tag->name]) ? trim($_POST[$tag->name]) : '';
 
-    $mailboxlayer_access_key = 'YOUR_ACCESS_KEY';
+    $options = get_option('wpcf7ev_options');
+
+    $mailboxlayer_access_key = $options['wpcf7ev_field_api_key'];
 
     $ch = curl_init('http://apilayer.net/api/check?access_key='.$mailboxlayer_access_key.'&email='.$email.'');
     curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
     $json = curl_exec($ch);
     curl_close($ch);
-    $validationResult = json_decode($json, true);
+    $response = json_decode($json, true);
 
-    if (!$validationResult['smtp_check']) {
-        $result->invalidate($tag, "This email address could not be verified!");
+    if ($response['error']) {
+        $error = $response['error']['info'];
+        switch ($options['wpcf7ev_field_on_error']) {
+            case 'email':
+                $body = "The mailboxlayer API returned an error.\n\nEmail: $email\n\nError: $error";
+                wp_mail(get_option('admin_email'), 'CF7 Email Validation Error', $body);
+                error_log("Sent mail to " . get_option('admin_email') . " about mailboxlayer API error.");
+                error_log("mailboxlayer API error when validating '" . $email . "': " . $error);
+                break;
+            case 'fail':
+                $result->invalidate($tag, "The email validation service returned an error.<br><small>Error: " . $error . "</small>");
+                error_log("mailboxlayer API error when validating '" . $email . "': " . $error);
+                break;
+            default:    
+                error_log("mailboxlayer API error when validating '" . $email . "': " . $error);
+        }
+    } else {
+        if (!$response['smtp_check']) {
+            $result->invalidate($tag, "This email address could not be verified!");
+        }
     }
 
     return $result;
 }
+
+/* Settings Page */
+
+function wpcf7ev_settings_init() {
+ // register a new setting for "wpcf7ev" page
+ register_setting( 'wpcf7ev', 'wpcf7ev_options' );
+ 
+ // register a new section in the "wpcf7ev" page
+ add_settings_section(
+ 'wpcf7ev_section_api',
+ __( 'Set up email validation for Contact Form 7 email fields here.', 'wpcf7ev' ),
+ 'wpcf7ev_section_api_cb',
+ 'wpcf7ev'
+ );
+ 
+ // register a new field in the "wpcf7ev_section_api" section, inside the "wpcf7ev" page
+ add_settings_field(
+ 'wpcf7ev_field_api_key',
+ __( 'API Key', 'wpcf7ev' ),
+ 'wpcf7ev_field_api_key_cb',
+ 'wpcf7ev',
+ 'wpcf7ev_section_api',
+ [
+ 'label_for' => 'wpcf7ev_field_api_key',
+ 'class' => 'wpcf7ev_row',
+ ]
+ );
+ 
+ // register a new field in the "wpcf7ev_section_api" section, inside the "wpcf7ev" page
+ add_settings_field(
+ 'wpcf7ev_field_on_error',
+ __( 'On Error', 'wpcf7ev' ),
+ 'wpcf7ev_field_on_error_cb',
+ 'wpcf7ev',
+ 'wpcf7ev_section_api',
+ [
+ 'label_for' => 'wpcf7ev_field_on_error',
+ 'class' => 'wpcf7ev_row',
+ ]
+ );
+}
+ 
+/**
+ * register our wpcf7ev_settings_init to the admin_init action hook
+ */
+add_action( 'admin_init', 'wpcf7ev_settings_init' );
+ 
+/**
+ * callback functions
+ */
+ 
+// api section cb
+ 
+// section callbacks can accept an $args parameter, which is an array.
+// $args have the following keys defined: title, id, callback.
+// the values are defined at the add_settings_section() function.
+function wpcf7ev_section_api_cb( $args ) {
+ ?>
+ <p id="<?php echo esc_attr( $args['id'] ); ?>"><?php _e( 'This plugin requires a ' . API_LINK . ' account.', 'wpcf7ev' ); ?></p>
+ <?php
+}
+ 
+ 
+// api_key field cb
+function wpcf7ev_field_api_key_cb( $args ) {
+ $options = get_option( 'wpcf7ev_options' );
+ ?>
+ <input id="<?php echo esc_attr( $args['label_for'] ); ?>"
+ type="text"
+ size=36
+ value="<?php echo esc_attr( $options[$args['label_for']] ); ?>"
+ name="wpcf7ev_options[<?php echo esc_attr( $args['label_for'] ); ?>]"
+ >
+ <p class="description">
+ <?php _e( 'Enter your ' . API_KEY_LINK . '.', 'wpcf7ev' ); ?>
+ </p>
+ <?php
+}
+
+// on_error field cb
+function wpcf7ev_field_on_error_cb( $args ) {
+ $options = get_option( 'wpcf7ev_options' );
+ $selected = $options['wpcf7ev_field_on_error'];
+ ?>
+ <select id="<?php echo esc_attr( $args['label_for'] ); ?>"
+ value="<?php echo esc_attr( $options[$args['label_for']] ); ?>"
+ name="wpcf7ev_options[<?php echo esc_attr( $args['label_for'] ); ?>]"
+ >
+<option value="email" <?php if ($selected == 'email') echo 'selected=selected'; ?>>Send email to site admin</option>
+<option value="fail" <?php if ($selected == 'fail') echo 'selected=selected'; ?>>Fail validation</option>
+<option value="log" <?php if ($selected == 'log') echo 'selected=selected'; ?>>Only generate a PHP error</option>
+</select>
+ <p class="description">
+ <?php _e( 'What to do when the API returns an error.', 'wpcf7ev' ); ?>
+ </p>
+ <?php
+}
+ 
+/**
+ * top level menu
+ */
+function wpcf7ev_options_page() {
+ // add top level menu page
+ add_menu_page(
+ 'Email Validation',
+ 'Email Validation Options',
+ 'manage_options',
+ 'wpcf7ev',
+ 'wpcf7ev_options_page_html'
+ );
+}
+ 
+/**
+ * register our wpcf7ev_options_page to the admin_menu action hook
+ */
+add_action( 'admin_menu', 'wpcf7ev_options_page' );
+ 
+/**
+ * top level menu:
+ * callback functions
+ */
+function wpcf7ev_options_page_html() {
+    // check user capabilities
+    if ( ! current_user_can( 'manage_options' ) ) {
+    return;
+    }
+    
+    // add error/update messages
+    
+    // check if the user have submitted the settings
+    // wordpress will add the "settings-updated" $_GET parameter to the url
+    if ( isset( $_GET['settings-updated'] ) ) {
+    // add settings saved message with the class of "updated"
+    add_settings_error( 'wpcf7ev_messages', 'wpcf7ev_message', __( 'Settings Saved', 'wpcf7ev' ), 'updated' );
+    }
+    
+    // show error/update messages
+    settings_errors( 'wpcf7ev_messages' );
+    ?>
+    <div class="wrap">
+    <h1><?php echo esc_html( get_admin_page_title() ); ?></h1>
+    <form action="options.php" method="post">
+    <?php
+    settings_fields( 'wpcf7ev' );
+    do_settings_sections( 'wpcf7ev' );
+    submit_button( 'Save Settings' );
+    ?>
+    </form>
+    </div>
+    <?php
+}
+
+
+?>