【WordPress】ウェブサイトのお問い合わせをSlackに通知する方法

function wp_slack_wpcf7_submit( $events ) {
  $events['wpcf7_submit'] = array(
    // Action in Gravity Forms to hook in to get the message.
    'action' => 'wpcf7_submit',
    // Description appears in integration setting.
    'description' => __( 'When someone sent message through Contact Form 7', 'slack' ),
    // Message to deliver to channel. Returns false will prevent
    // notification delivery.
    'message' => function( $form, $result ) {
      // @todo: Once attachment is supported in Slack
      // we can send payload with nicely formatted message
      // without relying on mail_sent result.
      $sent = (
        ! empty( $result['mail_sent'] )
        ||
        ( ! empty( $result['status'] ) && 'mail_sent' === $result['status'] )
      );
      if ( $sent ) {
        return apply_filters( 'slack_wpcf7_submit_message',
          sprintf(
            __( 'Someone just sent a message through *%s* _Contact Form 7_. Check your email!', 'slack' ),
            is_callable( array( $form, 'title' ) ) ? $form->title() : $form->title
          ),
          $form,
          $result
        );
      }
      return false;
    }
  );
  return $events;
}
add_filter( 'slack_get_events', 'wp_slack_wpcf7_submit' );

上記の強調されている場所を以下のように書き換えます。

if ( $sent ) {
  $submission = WPCF7_Submission::get_instance();
  $formdata = $submission->get_posted_data();
  $contents = "新しいお問い合わせが提出されました。\n\n";

  $fields = array(
    'your-name' => '名前',
    'your-email' => 'メールアドレス',
    'your-subject' => '題名',
    'your-message' => '本文',
  );

  foreach ($fields as $key => $label) {
    $val = isset($formdata[$key]) ? $formdata[$key] : '';
    $contents .= $label . ":\n" . $val . "\n\n";
  }

  return apply_filters(
    'slack_wpcf7_submit_message',
    $contents,
    $form,
    $result
  );
}

なお「your-name」「your-email」などは、Contact Form 7でフォームを設定するときに入力した値がそのまま反映されているので適宜編集してください。