AJAX & webhooks

Easy Invoice does not register custom REST routes. There are no /wp-json/easy-invoice/v1/... endpoints. Instead, the plugin uses two transports:

1. admin-ajax.php for in-page AJAX (search, save, send, mark paid, generate PDF).
2. Gateway webhooks for asynchronous payment notifications (Stripe, Mollie, Square, Authorize.Net) — also routed through admin-ajax.php.

If you're integrating Easy Invoice with another system, work via hooks & filters plus wp_remote_post against admin-ajax.php, or skip the HTTP layer entirely and call PHP services in-process.

admin-ajax actions

Each wp_ajax_<action> is the logged-in version; wp_ajax_nopriv_<action> is for non-logged-in (mostly gateway webhooks).

Invoice & quote management (logged-in only)

Action	Method	Caps	Purpose
easy_invoice_save_invoice	POST	manage_options	Save the invoice builder state.
easy_invoice_save_quote	POST	manage_options	Save the quote builder state.
easy_invoice_send_invoice	POST	manage_options	Trigger the invoice email.
easy_invoice_send_quote	POST	manage_options	Trigger the quote email.
easy_invoice_delete_invoice	POST	manage_options	Soft-delete (trash) an invoice.
easy_invoice_duplicate_invoice	POST	manage_options	PRO Clone an invoice.
easy_invoice_search_clients	POST	edit_posts	Autocomplete in the client field.
easy_invoice_search_invoices	POST	manage_options	Autocomplete on the payment form.
easy_invoice_search_items	POST	manage_options	PRO Autocomplete from Item Library.

All of the above are nonce-protected — pass _wpnonce (the admin script localizes one for you).

Reports

Action	Method	Purpose
easy_invoice_reports_data	GET	Returns Chart.js-ready data for a date range.

Quote accept / decline (visitor-facing)

Action	Method	Auth	Purpose
easy_invoice_quote_accept	POST	Public (token-gated)	Visitor accepts a quote.
easy_invoice_quote_decline	POST	Public (token-gated)	Visitor declines a quote.

These accept a one-time token in the URL — you should call them via the Accept / Decline buttons on the public quote page, not directly.

Gateway webhooks

Each Pro gateway registers a webhook hook so the gateway can call back when a payment status changes asynchronously.

Stripe

POST https://yoursite.com/wp-admin/admin-ajax.php?action=easy_invoice_stripe_webhook

• Configure in Stripe dashboard → Developers → Webhooks → Add endpoint.
• Events to subscribe: payment_intent.succeeded, payment_intent.payment_failed, charge.refunded.
• Stripe sends a Stripe-Signature header; Easy Invoice verifies it against your Signing secret.

Mollie

POST https://yoursite.com/wp-admin/admin-ajax.php?action=easy_invoice_mollie_webhook

• Mollie posts a payment_id; Easy Invoice fetches the payment via Mollie's API to verify status.

Square

POST https://yoursite.com/wp-admin/admin-ajax.php?action=easy_invoice_square_webhook

• Configure in Square dashboard → Apps → Webhook subscriptions.
• Events: payment.created, payment.updated, refund.created.
• A 15-minute reconcile cron (easy_invoice_check_pending_square_payments) fills in any webhook the listener missed.

Authorize.Net

POST https://yoursite.com/wp-admin/admin-ajax.php?action=easy_invoice_authorizenet_response

• This is the Relay Response URL you set in Authorize.Net's Silent Post.
• Easy Invoice verifies the MD5 hash if you've set one in the gateway settings.

Bank Transfer / Cheque / Cash / Manual

These have no webhooks — the admin marks the Payment record as completed manually after the funds arrive (see Payments).

Authentication notes

• admin-ajax logged-in actions: WordPress cookie + nonce. Use wp_create_nonce('easy_invoice_admin') and pass as _wpnonce POST field.
• Gateway webhooks: each gateway uses its own signature scheme (Stripe header, Mollie API check, Authorize.Net hash). Easy Invoice handles verification.

Programmatic alternative: in-process PHP

If you're inside the same WordPress install (custom plugin / theme code), skip HTTP entirely:

// Get an invoice
$invoice = new \EasyInvoice\Models\Invoice( $invoice_id );

// Mark as paid
$invoice->set_payment_status( 'completed' );
$invoice->save();

// Trigger the receipt email
do_action( 'easy_invoice_payment_completed', $payment_id );

This is faster, doesn't need nonces, and respects every filter/hook automatically.

What about a "real" REST API?

If you need a true /wp-json/easy-invoice/v1/invoices endpoint, you can add one yourself in a small mu-plugin that wraps the existing services:

add_action( 'rest_api_init', function () {
    register_rest_route( 'easy-invoice/v1', '/invoices/(?P<id>\d+)', [
        'methods'             => 'GET',
        'callback'            => function ( $request ) {
            $invoice = new \EasyInvoice\Models\Invoice( $request['id'] );
            return rest_ensure_response( $invoice->to_array() );
        },
        'permission_callback' => function () {
            return current_user_can( 'manage_options' );
        },
    ] );
} );

Apply the easy_invoice_model_to_array filter to control what's returned.

Rate limits & caching

• admin-ajax.php is uncached by default (most caching plugins exclude it).
• No built-in rate limit — protect with Cloudflare / WP Hide / Login Lockdown if you expose webhooks publicly.

Where to go next

• 🪝 Hooks & filters — extend behaviour in-process.
• 💳 Payment gateways — gateway-specific webhook URLs.
• 🛠️ Troubleshooting → Webhooks.