I have to build a little conference-site with a registration-form.
The conference is 1 day and has different sessions in the morning and different sessions in the afternoon. Those sessions have limited spaces available.
Users should be able to register for the conference by the registration-form and if there are no more spaces available for a specific session, they should get a message that this is no longer available, so that they have to choose another session.
What is the best solution for this, knowing that my client wants 1 registration form for the entire day. Otherwise I was considering entity_registration. With the "1 registration form" in mind, I was considering to use webform and webform_validation or webform_rules, but there is no standard solution for the limited spaces available.
Is there a good solution for this problem?
Can someone help me?