Booknetic includes a broad set of WordPress-compatible actions and filters that let developers extend, customize, and integrate the plugin without modifying core files. The hook system follows the familiar WordPress do_action() and apply_filters() pattern, so if you already work with WordPress plugin development, the structure will feel natural.

Backend hooks are the main extension layer for reacting to lifecycle events, modifying data before it is saved or rendered, registering addons, controlling permissions, and integrating with external systems such as CRMs, calendars, payment tools, and custom admin interfaces.

How Hooks Work

Booknetic uses two hook types:

• Actions let you run custom logic when a specific event happens, such as when an appointment is created, a payment is confirmed, or a customer is deleted.
• Filters let you modify a value before Booknetic uses or returns it, such as appointment insert data, calendar event data, booking panel assets, or capability checks.

Registering a Hook Listener

// Listen to an action
add_action('bkntc_appointment_created', function ($appointmentData) {
    // Your custom logic here
}, 10, 1);

// Listen to a filter
add_filter('bkntc_appointment_insert_data', function ($data) {
    $data['notes'] = 'Auto-generated note';
    return $data; // Always return the modified value
}, 10, 1);

Filters must always return a value. If you forget to return the modified value, the data will be lost and may cause errors.

Hook Naming Convention

All Booknetic hooks follow a consistent prefix-based naming pattern:

Actions

Actions are used when you want to react to something that has happened inside Booknetic.

Initialization & Bootstrap

bkntc_init

Fired after Booknetic is fully loaded and initialized. Use this hook when your custom code depends on Booknetic being available.

Parameters: None

add_action('bkntc_init', function () {
    // Booknetic is ready, register your custom logic
});

bkntc_frontend

Fired when a frontend page containing the booking panel is loaded.

Parameters: None

add_action('bkntc_frontend', function () {
    // Enqueue custom frontend scripts or styles
    wp_enqueue_script('my-custom-script', plugins_url('assets/custom.js', __FILE__));
});

bkntc_backend

Fired when the Booknetic admin panel is loaded.

Parameters: None

add_action('bkntc_backend', function () {
    // Add custom admin functionality
});

bkntc_cronjob

Fired during Booknetic cron job execution.

Parameters: None

Customer Actions

bkntc_customer_created

Fired when a new customer is created.

Parameters:

add_action('bkntc_customer_created', function ($customerId, $wpPassword) {
    // Send a welcome email, sync to CRM, etc.
    error_log("New customer created: #$customerId");
}, 10, 2);

bkntc_customer_saved

Fired after customer data is saved, both on create and update.

Parameters:

add_action('bkntc_customer_saved', function ($customerId) {
    // Sync updated customer data to external system
}, 10, 1);

bkntc_customer_before_edit

Fired before a customer record is updated. This is useful when you need to capture the old state before changes are applied.

Parameters:

bkntc_customer_deleted

Fired when a customer is deleted.

Parameters:

add_action('bkntc_customer_deleted', function ($customerId) {
    // Clean up related data in external systems
}, 10, 1);

bkntc_customer_sign_up_confirm

Fired when a customer confirms signup through email verification.

Parameters:

bkntc_customer_forgot_password

Fired when a customer requests a password reset.

Parameters:

bkntc_customer_reset_password

Fired after a customer password has been successfully reset.

Parameters:

Appointment Actions

bkntc_appointment_created

Fired when a new appointment is created, whether from the frontend booking panel or the backend admin side.

Parameters:

AppointmentRequestData (BookneticApp\Backend\Appointments\Helpers\AppointmentRequestData) provides access to:

add_action('bkntc_appointment_created', function (AppointmentRequestData $appointmentData) {
    $appointmentId = $appointmentData->appointmentId;
    $serviceId = $appointmentData->serviceId;
    $customerId = $appointmentData->customerId;
    $serviceName = $appointmentData->serviceInf->name;

    // Send notification, sync to external calendar, etc.
}, 10, 1);

bkntc_backend_appointment_created

Fired specifically when an appointment is created from the admin panel, not from the frontend booking panel.

Parameters:

bkntc_appointment_before_edit

Fired before an existing appointment is updated. Use this when you need to inspect or capture the current state before changes are applied.

Parameters:

add_action('bkntc_appointment_before_edit', function (AppointmentRequestData $appointmentObj) {
    // Store old state for comparison
    $oldStatus = $appointmentObj->appointmentInf->status;
    $oldStaffId = $appointmentObj->staffId;
}, 10, 1);

bkntc_appointment_after_edit

Fired after an appointment has been updated.

Parameters:

bkntc_appointment_before_mutation

Fired before an appointment undergoes any change. This includes status changes, edits, rescheduling, payment confirmation, and deletion. This is a general-purpose “before change” hook.

Parameters:

This hook fires in these contexts:

• Status changes such as approve, cancel, reject, and similar transitions
• Appointment edits such as date, time, staff, or service changes
• Appointment rescheduling
• Payment confirmation when status is updated after payment
• Appointment deletion, before bkntc_appointment_deleted

add_action('bkntc_appointment_before_mutation', function ($appointmentId) {
    if ($appointmentId === null) return;

    // Capture the current state before it changes
    $appointment = \BookneticApp\Models\Appointment::get($appointmentId);
    // Store old status, sync with external systems, etc.
}, 10, 1);

bkntc_appointment_after_mutation

Fired after an appointment has undergone a change. Like bkntc_appointment_before_mutation, this hook fires for status changes, edits, rescheduling, payment confirmation, and deletion. This is one of the most frequently used hooks in Booknetic. Calendar sync addons, video meeting addons, and logging addons commonly rely on it.

Parameters:

When this hook fires during deletion, $appointment_id is null because the record is about to be removed. If you need the real appointment ID before deletion, use bkntc_appointment_before_mutation. If you need deletion-specific logic, use bkntc_appointment_deleted.

add_action('bkntc_appointment_after_mutation', function ($appointmentId) {
    if ($appointmentId === null) {
        // Appointment was deleted — handle cleanup
        return;
    }

    // Sync with Google Calendar, create Zoom meeting, log changes, etc.
    $appointment = \BookneticApp\Models\Appointment::get($appointmentId);
}, 10, 1);

bkntc_appointment_deleted

Fired when an appointment is deleted. This hook runs after bkntc_appointment_before_mutation and bkntc_appointment_after_mutation have already been called for the deletion.

Parameters:

add_action('bkntc_appointment_deleted', function ($appointmentId) {
    // Clean up related data in external systems
    // Note: the appointment record may already be deleted from the database at this point
}, 10, 1);

bkntc_validate_appointment_reschedule

Fired during the validation phase of an appointment reschedule.

Parameters:

Appointment Request Actions

These hooks run during the booking flow while appointment request data is loaded, processed, and validated.

bkntc_appointment_request_data_load

Fired when appointment request data is loaded for a single booking request.

Parameters:

bkntc_appointment_requests_load

Fired after all appointment requests have been loaded, such as when a cart contains multiple bookings.

Parameters: None

bkntc_appointment_requests_validate

Fired during validation of the full appointment request collection.

Parameters:

bkntc_after_appointment_requests_validate

Fired after appointment request validation is completed.

Parameters:

bkntc_appointment_request_before_data_validate

Fired before a single appointment request data entry is validated.

Parameters:

bkntc_appointment_request_data_validate

Fired during validation of a single appointment request data entry.

Parameters:

bkntc_handle_any_staff_on_step

Fired when “Any staff” is selected during the booking flow, allowing you to customize staff assignment behavior.

Parameters:

bkntc_booking_step_confirmation_validation

Fired during confirmation step validation in the booking panel.

Parameters: None

Payment Actions

bkntc_payment_confirmed

Fired when payment is confirmed for an appointment.

Parameters:

add_action('bkntc_payment_confirmed', function ($appointmentId, $method = null) {
    // Generate invoice, send receipt, etc.
}, 10, 2);

bkntc_payment_completed

Fired when a payment flow is fully completed, including gateway confirmation.

Parameters:

bkntc_payment_confirmed_backend

Fired when payment is confirmed from the admin panel.

Parameters:

bkntc_payment_canceled

Fired when a payment is canceled.

Parameters:

Staff Actions

bkntc_staff_created

Fired when a new staff member is created.

Parameters:

add_action('bkntc_staff_created', function ($staffId) {
    // Assign a WordPress user role, send welcome email, etc.
}, 10, 1);

bkntc_after_request_staff_save_staff

Fired after a staff member has been saved through the admin panel.

Parameters:

Service & UI Actions

bkntc_service_model_scopes

Fired when service model query scopes are being applied.

Parameters:

bkntc_service_defaults_serviceInf

Fired when default service information is being loaded.

Parameters:

bkntc_enqueue_assets

Fired when Booknetic admin panel assets are being enqueued. Use this to load addon scripts and styles only on the admin pages where they are needed.

Parameters:

add_action('bkntc_enqueue_assets', function ($module, $action, $viewPath) {
    if ($module === 'appointments') {
        wp_enqueue_script('my-addon-script', plugins_url('assets/script.js', __FILE__));
    }
}, 10, 3);

bkntc_module_calendar_loaded

Fired when the calendar module view is loaded.

Parameters: None

Booking Panel View Actions

These hooks let you inject custom HTML and UI fragments into specific parts of the booking panel.

bkntc_after_booking_panel_shortcode

Fired after the booking panel shortcode output.

Parameters: None

bkntc_after_information_inputs

Fired after the standard fields in the Information step of the booking panel. This is commonly used to add custom input fields.

Parameters:

add_action('bkntc_after_information_inputs', function ($serviceObj) {
    echo '<div class="form-group">';
    echo '<label>Special Request</label>';
    echo '<textarea name="special_request" class="form-control"></textarea>';
    echo '</div>';
}, 10, 1);

bkntc_service_step_footer

Fired at the bottom of the Services step.

Parameters:

bkntc_service_extras_step_footer

Fired at the bottom of the Service Extras step.

Parameters:

Dynamic Tab Item Actions

bkntc_tabitem_{tabSlug}_{slug}_{section}

This is a dynamic hook pattern for injecting content into admin panel tab items.

The hook name is built from:

• {tabSlug} — the tab group identifier such as appointments
• {slug} — the specific tab slug such as edit_details
• {section} — the section inside the tab such as duration_after

Parameters:

Example:

add_action('bkntc_tabitem_appointments_edit_details_duration_after', function ($tabItem, $args) {
    echo '<div class="my-custom-section">Custom content here</div>';
}, 10, 2);

Filters

Filters are used when you need to change data before Booknetic saves it, renders it, returns it, or passes it into another layer.

Query & Data Filters

bkntc_appointment_insert_data

Modify appointment data before it is inserted into the database.

Parameters:

Returns: array — The modified data array

add_filter('bkntc_appointment_insert_data', function ($data) {
    // Add a custom note to every new appointment
    $data['note'] = 'Created via custom integration';
    return $data;
}, 10, 1);

bkntc_appointment_update_data

Modify appointment data before it is updated in the database.

Parameters:

Returns: array

bkntc_appointment_reschedule

Modify appointment data during a reschedule operation.

Parameters:

Returns: array

bkntc_appointment_data_service_extras

Modify service extras data for an appointment.

Parameters:

Returns: array

bkntc_selected_time_slot_info

Modify selected time slot information during the booking flow.

Parameters:

Returns: object

bkntc_set_service_duration_frontend

Override the service duration displayed in the frontend booking panel.

Parameters:

Returns: Service\|Collection

bkntc_query_builder_global_scope

Control whether the global query scope should be applied, such as tenant filtering or staff-based filtering.

Parameters:

Returns: bool

add_filter('bkntc_query_builder_global_scope', function ($applyScope) {
    // Bypass global scope for specific operations
    return false;
}, 10, 1);

Booking Panel Rendering Filters

bkntc_booking_panel_render_staff_info

Modify staff information displayed in the staff selection step of the booking panel.

Parameters:

Returns: array

add_filter('bkntc_booking_panel_render_staff_info', function ($staffInfo) {
    // Add a custom badge or modify display data
    foreach ($staffInfo as &$staff) {
        $staff['name'] .= ' (Available)';
    }
    return $staffInfo;
}, 10, 1);

bkntc_booking_panel_render_services_info

Modify service information displayed in the service selection step of the booking panel.

Parameters:

Returns: array

bkntc_booking_panel_render_service_extras_info

Modify service extras information displayed in the booking panel.

Parameters:

Returns: array

bkntc_booking_panel_information_step_parameters

Modify the parameters passed to the Information step view.

Parameters:

Returns: array

bkntc_extras_step_components

Modify the components rendered in the Extras step.

Parameters:

Returns: array

Calendar & Slot Filters

bkntc_busy_slots

Modify the list of busy or unavailable time slots. Calendar sync addons commonly use this to inject external calendar events into Booknetic availability.

Parameters:

Returns: array

add_filter('bkntc_busy_slots', function ($busySlots, CalendarService $calendarService) {
    // Add external calendar events as busy slots
    $busySlots[] = [
        'start_time' => '09:00',
        'end_time'   => '10:00',
        'date'       => '2025-01-15',
        'staff_id'   => 1,
    ];
    return $busySlots;
}, 10, 2);

bkntc_show_busy_time_slot

Control whether fully booked time slots should still be visible in the booking panel.

Parameters:

Returns: bool

bkntc_calendar_service_disable_slot

Control whether a specific time slot should be disabled and unselectable in the booking panel.

Parameters:

Returns: bool

bkntc_calendar_events

Modify events displayed on the admin calendar. Calendar sync addons use this to display external events alongside native Booknetic appointments.

Parameters:

Returns: array

add_filter('bkntc_calendar_events', function ($events, $startTime, $endTime, $staffFilter) {
    // Add events from an external source
    $events[] = [
        'id'        => 'external_1',
        'title'     => 'External Event',
        'start'     => '2025-01-15T09:00:00',
        'end'       => '2025-01-15T10:00:00',
        'color'     => '#ff9800',
    ];
    return $events;
}, 10, 4);

bkntc_filter_calendar_event_object

Modify a single calendar event object before it is rendered.

Parameters:

Returns: array

Step Verification Filters

bkntc_post_step_verification

Add custom verification logic after a booking step is submitted. Return false to block step progression.

Parameters:

Returns: bool

bkntc_pre_step_verification

Add custom verification logic before a booking step is loaded.

Parameters:

Returns: bool

bkntc_hide_method_selecting

Control whether payment method selection should be hidden in the booking panel.

Parameters:

Returns: bool

Capability & Permission Filters

bkntc_user_capability_filter

Override user capability checks. This is used by addons such as User Role Manager to implement custom permission logic.

Parameters:

Returns: bool

add_filter('bkntc_user_capability_filter', function ($can, $capability) {
    // Restrict a specific capability for non-admin users
    if ($capability === 'appointments_delete' && !current_user_can('administrator')) {
        return false;
    }
    return $can;
}, 10, 2);

bkntc_capability_limit_filter

Override capability limits such as the maximum number of appointments or staff members.

Parameters:

Returns: int

bkntc_tenant_capability_filter

Override tenant-level capability checks. In SaaS mode, this is used to control access to features based on plan capabilities.

Parameters:

Returns: bool

Appointment Status Filters

bkntc_appointment_statuses

Modify the list of available appointment statuses. This hook is used when you want to register custom appointment states.

Parameters:

Returns: array

Each status item should follow this structure:

add_filter('bkntc_appointment_statuses', function ($statuses) {
    $statuses[] = [
        'slug'  => 'in_progress',
        'title' => 'In Progress',
        'color' => '#2196F3',
        'icon'  => 'fa fa-spinner',
        'busy'  => true,
    ];
    return $statuses;
}, 10, 1);

bkntc_price_name

Modify how a price label is displayed.

Parameters:

Returns: string

Settings & Export Filters

bkntc_whitelist_translation_tables

Add database tables to the translation whitelist so addon data can participate in multi-language functionality.

Parameters:

Returns: array

bkntc_add_tables_for_export

Add custom database tables to the backup and export process.

Parameters:

Returns: array

add_filter('bkntc_add_tables_for_export', function ($tables) {
    $tables[] = 'my_addon_table';
    return $tables;
}, 10, 1);

bkntc_labels_settings_translates

Modify translatable booking label settings.

Parameters:

Returns: array

bkntc_save_booking_labels_settings

Modify label data before it is saved.

Parameters:

Returns: array

Localization & Response Filters

bkntc_localization

Add or modify localization strings passed into admin panel JavaScript. Use this hook to expose your addon strings to the frontend interface.

Parameters:

Returns: array

add_filter('bkntc_localization', function ($strings) {
    $strings['my_addon_label'] = __('My Custom Label', 'my-addon');
    $strings['my_addon_confirm'] = __('Are you sure?', 'my-addon');
    return $strings;
}, 10, 1);

bkntc_frontend_localization

Works like bkntc_localization, but for frontend booking panel JavaScript.

Parameters:

Returns: array

bkntc_response

Modify AJAX response data before it is returned to the client.

Parameters:

Returns: array

bkntc_after_frontend_request_{method}

A dynamic filter that fires after a frontend AJAX request is processed. {method} is replaced with the actual AJAX method name.

Parameters:

Returns: mixed

Asset & Addon Filters

bkntc_booking_panel_assets

Modify the list of JavaScript and CSS assets loaded on the booking panel.

Parameters:

Returns: array

add_filter('bkntc_booking_panel_assets', function ($assets) {
    $assets[] = [
        'type' => 'js',
        'url'  => plugins_url('assets/my-booking-addon.js', __FILE__),
    ];
    $assets[] = [
        'type' => 'css',
        'url'  => plugins_url('assets/my-booking-addon.css', __FILE__),
    ];
    return $assets;
}, 10, 1);

bkntc_addons_load

Register your addon with Booknetic. This is the primary integration hook used by every addon loader.

Parameters:

Returns: array

add_filter('bkntc_addons_load', function ($addons) {
    $addons[] = \BookneticAddon\MyAddon\MyAddonLoader::class;
    return $addons;
}, 10, 1);

bkntc_short_code_before_replace

Modify shortcode content before shortcode placeholders are replaced with actual values.

Parameters:

Returns: string

bkntc_short_code_after_replace

Modify shortcode content after all placeholders have been replaced.

Parameters:

Returns: string

UI Filters

bkntc_datatable_after_render

Add custom content after a DataTable is rendered in the admin panel. This is useful for custom columns, summary rows, or extra interface fragments.

Parameters:

Returns: string

bkntc_tabitem_{tabSlug}_{slug}_{section}_before

Inject HTML before a specific section in a tab item.

Returns: string

bkntc_tabitem_{tabSlug}_{slug}_{section}_end

Inject HTML at the end of a specific section in a tab item.

Returns: string

SaaS Module Actions

These hooks are available when the Booknetic SaaS module is active. They use the bkntcsaas_ prefix.

Initialization

bkntcsaas_init

Fired after the SaaS module is fully initialized.

Parameters: None

bkntcsaas_frontend

Fired when the SaaS frontend, such as signup and login pages, is loaded.

Parameters: None

bkntcsaas_backend

Fired when the SaaS admin panel is loaded.

Parameters: None

Tenant Lifecycle

bkntcsaas_tenant_created

Fired when a new tenant is created.

Parameters:

add_action('bkntcsaas_tenant_created', function ($tenantId) {
    // Set up default data for the new tenant
    // Send onboarding email, etc.
}, 10, 1);

bkntcsaas_tenant_deleted

Fired when a tenant is deleted.

Parameters:

bkntcsaas_tenant_subscribed

Fired when a tenant subscribes to a plan.

Parameters:

bkntcsaas_tenant_unsubscribed

Fired when a tenant subscription is canceled or expires.

Parameters:

bkntcsaas_tenant_paid

Fired when a tenant makes a payment.

Parameters:

Tenant Authentication

bkntcsaas_tenant_sign_up_confirm

Fired when a signup confirmation email is sent to a tenant.

Parameters:

bkntcsaas_tenant_sign_up_confirm_resend

Fired when a signup confirmation email is resent.

Parameters:

bkntcsaas_tenant_sign_up_completed

Fired when a tenant completes signup, meaning the email is verified and the account is active.

Parameters:

bkntcsaas_tenant_reset_password

Fired when a tenant requests a password reset.

Parameters:

bkntcsaas_tenant_reset_password_completed

Fired after a tenant password has been successfully reset.

Parameters:

Billing

bkntcsaas_tenant_deposit_paid

Fired when a tenant deposit payment is processed.

Parameters:

bkntcsaas_tenant_deposit_added

Fired when a deposit is added to a tenant account.

Parameters:

Summary

Booknetic backend hooks provide a complete extension layer for core lifecycle events, booking flow processing, calendar integration, permissions, assets, UI injection, addon loading, and SaaS tenant workflows.

Quick Reference: Most Used Hooks