Send Emails Developer Reference — Hooks, Filters & REST API

Send Emails is built to be extended: PSR-4 classes under the SendEmails namespace, custom indexed tables for all data (nothing in wp_posts/wp_postmeta), a REST API that the admin itself runs on, and hooks at every meaningful point. The Send Emails Pro add-on is built entirely on the extension points below — anything Pro can do, your code can too.

Sending emails programmatically

sende_send_email( array(
    'to'      => 'someone@example.com',
    'subject' => 'Hello from code',
    'message' => '<p>HTML body</p>',
) );

Every send — yours, compose, campaigns, automations — flows through one mailer, gets logged, and respects the tracking settings.

Email filters

Modify any outgoing email just before it sends:

Filter	Filters
`sende_email_to`	Recipient address(es)
`sende_email_subject`	Subject line
`sende_email_body`	Body content
`sende_email_headers`	Header array
`sende_email_attachments`	Attachments array

After the result is logged, sende_email_sent or sende_email_failed fires with the log model. The pre-2.6 sendemails_email_*, sendemails_merge_tags and sendemails_form_submitted hook names still fire but are deprecated since 2.6.0.

Merge tags

Add custom tags via sende_merge_tags — see the example on the Merge Tags page. Related: sende_unsubscribe_footer filters the auto-appended footer.

Model lifecycle hooks

Every entity (contact, tag, email, campaign, automation) fires lifecycle actions:

sende_pre_insert_{type} / sende_inserted_{type}
sende_pre_update_{type} / sende_updated_{type}
sende_pre_delete_{type} / sende_deleted_{type}
Status transition hooks such as sende_contact_status_transition — the automation engine itself listens to these, e.g. for the contact subscribed trigger.

add_action( 'sende_inserted_contact', function ( $contact ) {
    error_log( 'New contact: ' . $contact->email );
} );

Form integrations

sende_form_submitted — action fired for every captured form submission (contact, mapped data, integration).
sende_form_integrations — register your own integration class for an unsupported form plugin; extend the abstract FormIntegration, which provides field auto-mapping, opt-in handling, dedupe-by-email, and tag assignment for free.

Automations & commerce

sende_automation_triggers — register custom automation triggers.
sende_fire_automation_trigger — fire a trigger from your own code (this is exactly how Pro’s birthday trigger works).
sende_purchase — fired by the WooCommerce/EDD integrations on paid orders; sende_attribution_window filters the revenue-attribution window (default 7 days).
sende_queue_batch_size — campaign queue batch size per cron tick.

Admin & settings extension points

These are the seams the Pro plugin plugs into:

PHP: sende_rest_controllers (add REST controllers to sende/v1), sende_settings_fields (register settings keys + sanitizers), sende_admin_app_data (extend the React app’s boot data), sende_admin_screen_ids, sende_manager_capability (change the required capability), and the send_emails_init action.
JS: sende.admin.pages (register admin app pages), sende.admin.settingsPanels (add settings panels), sende.admin.contactFormFields (inject contact form fields) — all via @wordpress/hooks.

Settings are read with sende_get_settings( $key, $default ).

REST API

Namespace: sende/v1. The React admin uses these endpoints exclusively, so they’re first-class and stable. Authenticated routes require the manager capability (cookie + nonce, or application passwords):

Route	Purpose
`/sende/v1/contacts`	Contacts CRUD, search/filter/pagination, bulk delete, CSV import/export endpoints
`/sende/v1/tags`	Tags CRUD
`/sende/v1/campaigns`	Campaigns CRUD + send/test/pause/resume/recipient-count
`/sende/v1/emails`	Send, logs collection/detail, resend, delete, `/emails/stats`
`/sende/v1/settings`	Read/update settings
`/sende/v1/track/open/{token}`	Public — open-tracking pixel
`/sende/v1/track/click/{token}`	Public — signed click redirect
`/sende/v1/unsubscribe/{uuid}`	Public — unsubscribe page (GET) and RFC 8058 one-click (POST)

curl -u user:app-password "https://example.com/wp-json/sende/v1/contacts?per_page=10&status=subscribed"

Data storage

Tables (all with the WordPress prefix): sende_contacts, sende_contactmeta, sende_tags, sende_contact_tags, sende_emails, sende_emailmeta, sende_campaigns, sende_automations, sende_automation_runs. Settings live in the sende_settings option. Prefer the models/REST API over raw SQL — the model layer maintains its own object cache.