Guests register for your events with free or paid tickets, and you check them in at the door by their code.
For an organiser of workshops, meetups or a wedding.
Start the event registration and tickets blueprint on Typestate
Asked you for your website's address and the address your emails come from.
Started Event registration and tickets: 3 record types, 6 web endpoints.
9 actions are compiling.
Deployed to Sandbox. Try it at your Sandbox address.
Each step has 3 parts: who starts it, how it reaches your backend, and the action that answers.
The rule you will want to change first
A paid ticket cancelled more than 48 hours before the start is refunded in full, and the seat goes back.
It lives in the action Cancel a Registration. Tell your agent how you want it instead: one sentence changes, and you read the change before it goes Live.
The map shows the records it keeps, the actions it runs and the services it calls.
What it keeps
What it does
What it reaches
One event, with its start and its place.
Everyone sees the events. Only your key adds and changes them.
One kind of ticket for an event, free or paid, with its seats.
Everyone sees the ticket types. Only your key adds and changes them.
One guest's seat, with the code they show at the door.
A guest registers and cancels through the actions, the payment confirms, and your key checks in. Only your key deletes one.
Open an action to read its steps: each sentence, with the calls that do it under it.
From the webPOST /events
Titletext, needed
Starts ata date and time, needed
Placetext, needed
Descriptiontext, optional
TicketsList, needed
When the given start is now or earlier, refuse with "An event starts in the future".When fewer than 1 or more than 10 ticket types are given, refuse with "Give between 1 and 10 ticket types".
When input.starts_at is on or before now
Refuse "An event starts in the future"
When number of input.tickets is less than 1
or number of input.tickets is more than 10
Refuse "Give between 1 and 10 ticket types"
Create an Event with the given title, starts_at, place and description, and slug set to the title written for a web address.
Add an Event
set description to input.description
set place to input.place
set slug to the slug of the given title, for a web address
set starts_at to input.starts_at
set title to input.title
For each given ticket type, create a TicketType with event_id set to that Event's id, and name, paid and seats set to the given name, paid and seats.
For each ticket in input.tickets
Add a TicketType
set event_id to event.id
set name to ticket.name
set paid to ticket.paid
set seats to ticket.seats
Answer with that Event's slug.
Answer
slug is event.slug
From the webGET /events
Nothing. It needs no input.
List the Events whose state is open and whose starts_at is after now, earliest first.
events is
Find Events where
starts_at is after now
state is "open"
sorted by starts_at, lowest first
For each Event, list the TicketTypes whose event_id is its id, and answer its title, slug, starts_at, place and description, with the id, name, paid and seats of each TicketType.
rows is an empty list
For each event in events
types is
Find TicketTypes where
event_id is event.id
Adds an object with (description = the event's description, place = the event's place, slug = the event's slug, starts at = the event's starts at, tickets = for each item of the value named types, as type, an object with (name = the type's name, paid = the type's paid, seats = the type's seats, ticket = the type's id), title = the event's title) to rows.
Answer
events is rows
From the webPOST /events/register
Tickettext, needed
Nametext, needed
EmailEmail, needed
Find the TicketType whose id is the given ticket.When none matches, refuse with "No such ticket".
type is
Find the first TicketType where
id is input.ticket
when none refuse "No such ticket"
Find the Event whose id is that TicketType's event_id.When none matches, or its state is not open, or its starts_at is now or earlier, refuse with "Registration for this event is closed".
event is
Find the first Event where
id is type.event_id
when none refuse "Registration for this event is closed"
When event.state is not "open"
or event.starts_at is on or before now
Refuse "Registration for this event is closed"
The seats taken are the count of Registrations for that TicketType whose state is confirmed or checked_in, plus those whose state is pending and that were made in the last hour.When the seats taken are that TicketType's seats or more, refuse with "These tickets are sold out".
A payment page left open for an hour gives its seat back, so a guest who walks away does not keep a seat.
held is
Count Registrations where
state is one of "confirmed" or "checked_in"
ticket_type_id is type.id
paying is
Count Registrations where
created_at is after now - 1 hour
state is "pending"
ticket_type_id is type.id
When held + paying is at least type.seats
Refuse "These tickets are sold out"
Create a Registration with event_id and ticket_type_id set to that Event's and that TicketType's ids, name and email set to the given name and email, starts_at set to that Event's starts_at, a new code of 10 random letters and digits, and state set to pending when that TicketType is paid, and to confirmed when it is free.
Add a Registration
set code to a random code of 10 letters and digits
set email to input.email
set event_id to event.id
set name to input.name
set starts_at to event.starts_at
set state to "pending" when the type's paid is true, otherwise "confirmed"
set ticket_type_id to type.id
When that TicketType is paid, open a payment page for the Ticket product, with the registration's code as the reference and the given email as the payer's email, and answer with the code and the address of that payment page.
When type.paid
page is
Open a payment page for Ticket
for is input.email
reference is registration.code
Answer
code is registration.code
payment_url is page.url
Otherwise email the given email with the subject "You are registered", saying that Event's title, its start, its place and the registration's code.
Send an email
to input.email
template "Registration Email"
code registration.code
place event.place
starts_at date and time of event.starts_at
title event.title
Answer with the registration's code.
Answer
code is registration.code
Referencetext, needed
Paymenttext, needed
A payment for a ticket succeeded.Find the Registration whose code is the payment's reference.When none matches, refuse with "No registration matches this payment".
registration is
Find the first Registration where
code is input.reference
when none refuse "No registration matches this payment"
Change that Registration's state to confirmed and its payment to the payment's id.
Change the Registration where
id is registration.id
set payment to input.payment
set state to "confirmed"
Find the Event whose id is that Registration's event_id.When none matches, refuse with "No such event".
event is
Find the first Event where
id is registration.event_id
when none refuse "No such event"
Email that Registration's email with the subject "You are registered", saying that Event's title, its start, its place and the registration's code.
Send an email
to registration.email
template "Registration Email"
code registration.code
place event.place
starts_at date and time of event.starts_at
title event.title
Registrationtext, needed
Find the Registration whose id is the given registration.When none matches, refuse with "No such registration".
registration is
Find the first Registration where
id is input.registration
when none refuse "No such registration"
When that Registration's state is not cancelled, or it has no payment, refuse with "Only a cancelled paid ticket is refunded".
When registration.state is not "cancelled"
or registration.payment holds no value
Refuse "Only a cancelled paid ticket is refunded"
Refund that Registration's payment in full, as requested by the guest.
Refund
payment registration.payment
amount all of it
From the webPOST /events/cancel
Codetext, needed
EmailEmail, needed
Find the Registration whose code is the given code and whose email is the given email.When none matches, refuse with "No registration matches this link".
registration is
Find the first Registration where
code is input.code
email is input.email
when none refuse "No registration matches this link"
When that Registration's state is cancelled or checked_in, refuse with "This registration cannot be cancelled".
When registration.state is one of "cancelled" or "checked_in"
Refuse "This registration cannot be cancelled"
When that Registration's starts_at is now or earlier, refuse with "This event has started, so the registration cannot be cancelled".
When registration.starts_at is on or before now
Refuse "This event has started, so the registration cannot be cancelled"
Change that Registration's state to cancelled.
Change the Registration where
id is registration.id
set state to "cancelled"
When that Registration has a payment and its starts_at is more than 48 hours from now, refund that payment in full in the background, with Refund a Cancelled Ticket.
Up to 48 hours before the start, a freed seat can still go to another guest.
refunded is
registration.payment holds a value
and hours from now to registration.starts_at is more than 48
When refunded
Run Refund a Cancelled Ticket in the background
registration is registration.id
Email that Registration's email with the subject "Your registration is cancelled", saying whether the payment is refunded.
Send an email
to registration.email
template "Cancel a Registration Email"
value "Your payment is being refunded in full." when the value named refunded is true, otherwise "No payment is refunded."
Answer with cancelled as the state, and whether the payment is refunded.
Answer
refunded is refunded
state is "cancelled"
From the webPOST /events/check-in
Codetext, needed
Find the Registration whose code is the given code in capital letters.When none matches, refuse with "No such ticket code".
registration is
Find the first Registration where
code is the given code in capital letters
when none refuse "No such ticket code"
When that Registration's state is checked_in, refuse with "This ticket was checked in already".When its state is not confirmed, refuse with "This ticket is not confirmed".
When registration.state is "checked_in"
Refuse "This ticket was checked in already"
When registration.state is not "confirmed"
Refuse "This ticket is not confirmed"
Change that Registration's state to checked_in.
Change the Registration where
id is registration.id
set state to "checked_in"
Answer with that Registration's name, and checked_in as the state.
Answer
name is registration.name
state is "checked_in"
From the webGET /events/attendees
Eventtext, needed
Find the Event whose slug is the given event.When none matches, refuse with "No such event".
event is
Find the first Event where
slug is input.event
when none refuse "No such event"
List the Registrations whose event_id is that Event's id and whose state is confirmed or checked_in, first registered first.
guests is
Find Registrations where
event_id is event.id
state is one of "confirmed" or "checked_in"
sorted by created_at, lowest first
For each Registration, answer its name, email, code and state, and answer the count of those that are checked_in.
rows is
each guest of guests as
code is guest.code
email is guest.email
name is guest.name
state is guest.state
Answer
checked_in is the number of the items of the value named guests, each as guest, where the guest's state is "checked_in"
guests is rows
A timer, every hour at 00 past
Nothing. It needs no input.
List the Registrations whose state is confirmed, whose reminded is false, and whose starts_at is from now up to 24 hours from now.
guests is
Find Registrations where
reminded is false
starts_at {"after":{"context":"now"},"on_or_before":{"add_hours":[{"context":"now"},24]}}
state is "confirmed"
For each of those Registrations, email its email with the subject "See you tomorrow", saying its starts_at and its code, and change its reminded to true.
For each guest in guests, at most 50
Send an email
to guest.email
template "Remind Tomorrow's Guests Email"
code guest.code
starts_at date and time of guest.starts_at
Change the Registration where
id is guest.id
set reminded to true
People sign up and sign in with an email address and a password, or with a provider you add, such as Google.
| What it does | Who may call | Address |
|---|---|---|
| Your site lists the coming events. | anyone | GET /events |
| Your site posts each registration here. | anyone | POST /events/register |
| A guest cancels with their code and email. | anyone | POST /events/cancel |
| Only you, with your key, add an event. | you, with your key | POST /events |
| Only your team, with your key, checks a guest in. | you, with your key | POST /events/check-in |
| Only you, with your key, read the guests. | you, with your key | GET /events/attendees |
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7 actionsEach sale and delivery moves the stock, and the owner gets one email when a product runs low.
5 actionsPeople join a waiting list from your page, and each friend they bring moves them up.
4 actions