# Hooks and the REST API - Bookline 1.x documentation

> The actions, filters and REST endpoints for extending Bookline.

Bookline Pro is built entirely on these hooks, so they're stable.

## Loading

`bookline_loaded` fires once Bookline has loaded (on `plugins_loaded`). Start add-ons there; the `Extendiment\Bookline\*` classes and `BOOKLINE_*` constants are available.

## Bookings

```php
add_action( 'bookline_booking_created', function ( $booking, $data ) {
	// $booking is an Extendiment\Bookline\Booking: ->id, ->start, ->end, ->email, ->status…
}, 10, 2 );
```

| Hook | When |
|---|---|
| `bookline_booking_created` (`$booking, $data`) | A booking was made. |
| `bookline_booking_status_changed` (`$booking, $old_status, $by`) | Its status changed; `$by` is customer, admin or system. |
| `bookline_booking_rescheduled` (`$booking, $before, $by`) | It moved. |
| `bookline_booking_updated` (`$booking, $before`) | Its details changed. |
| `bookline_booking_delete` (`$booking`) | It's about to be deleted. |
| `bookline_booking_anonymised` (`$booking`) | Its personal data was erased. |

Filters: `bookline_validate_booking` (return a `WP_Error` to refuse a booking), `bookline_initial_status`, `bookline_statuses` (add a status), `bookline_freeing_statuses`, `bookline_changeable_statuses`, `bookline_booking_details` (rows shown in emails and on pages), `bookline_booking_public`.

## Availability

| Filter | Use |
|---|---|
| `bookline_busy_times` (`$busy, $staff, $from, $to`) | Add busy periods, e.g. from another calendar: return `[ [ $start, $end ], … ]` timestamps. |
| `bookline_slots` (`$slots, $service, $date, $args`) | Change a day's slots. |
| `bookline_slot_interval` | Minutes between start times for a service. |
| `bookline_service_staff`, `bookline_schedule`, `bookline_busy_staff`, `bookline_parallel_services`, `bookline_pick_staff` | Staff members with their own schedules (Bookline Pro). |

## The form

- `bookline_form_steps` adds steps; print a step on `bookline_form_step_{key}`.
- `bookline_form_details_fields` prints more fields in "Your details". Inputs with `data-bookline-field="key"` are sent along as `fields[key]`, and reach `bookline_validate_booking` and `bookline_booking_created` in `$data['params']['fields']`.
- `bookline_form_config` adds data for the form's script.
- `bookline_booking_response`: the answer to a new booking. Add `redirect` to send the customer to another page (for example to pay), or `error` to show a message.
- `bookline_booking_paid` (`$paid, $booking`): whether a booking was paid for online, so the customer's booking page confirms the payment after `?bookline_done=paid`.

The form's script has `wp.hooks` too: `bookline.form.init`, `bookline.form.step`, `bookline.form.skip`, `bookline.form.validate`, `bookline.availability.params`, `bookline.booking.payload`, `bookline.summary.rows` and `bookline.booked`.

## Emails

`bookline_emails` adds an email (editable on the Emails tab); send it with `Extendiment\Bookline\Emails::send( $key, $booking )`. Also `bookline_send_email`, `bookline_email_recipients`, `bookline_email_attachments`, `bookline_email_placeholders` and `bookline_ics_event`.

## Admin screens

`bookline_admin_menu`, `bookline_settings_tabs` with `bookline_settings_tab_{key}`, `bookline_service_fields` and `bookline_save_service`, `bookline_booking_screen_fields`, `bookline_booking_screen_main`, `bookline_booking_screen_side`, `bookline_bookings_columns`, `bookline_calendar_filters`, and who sees what: `bookline_can_view_bookings`, `bookline_bookings_query_args`, `bookline_edit_booking_caps`.

## REST API

Namespace `bookline/v1`:

| Endpoint | |
|---|---|
| `GET services` | Bookable services. |
| `GET availability/days?service=&month=YYYY-MM&seats=` | Each day of a month: open, full or closed. |
| `GET availability/slots?service=&date=YYYY-MM-DD&seats=` | The day's time slots. |
| `POST bookings` | Make a booking (`service`, `start` timestamp, `seats`, `name`, `email`, `phone`, `notes`, and the `nonce` from an availability answer). |
| `GET bookings/{key}`, `POST bookings/{key}/cancel`, `POST bookings/{key}/reschedule` | A customer's booking, by its key. |
| `GET bookings?from=&to=` | Bookings, for people who can view them. |

## Other filters

`bookline_now` (the current time, for tests), `bookline_lock_timeout`, `bookline_client_ip` (behind a proxy), `bookline_format_price`.

Source: https://extendiment.com/plugins/bookline/docs/1.x/hooks