Transport Channels

PSAPLink Cloud supports 11 pluggable transport channels. All implement TransportHandlerInterface.

Available Transports

Slug	Provider	Inbound ACK
email	Symfony Mailer (SMTP / SES / Postmark)	✅ Yes
sms	Twilio REST API	✅ Yes
webhook	HMAC-signed JSON HTTP POST	✅ Yes
ntfy	ntfy.sh topic push	No
slack	Slack Incoming Webhooks	No
teams	Microsoft Teams Connector Cards	No
pagerduty	PagerDuty Events API v2	No
discord	Discord Webhooks	No
cap	CAP 1.2 XML	No
pager_snpp	SNPP pager (RFC 1861)	No
push	FCM / APNs	No

Transports that support Inbound ACK can receive replies from recipients and automatically mark notifications acknowledged.

Transport Interface

interface TransportHandlerInterface
{
    public function getSlug(): string;
    /** Send a notification. $config is already decrypted. */
    public function send(NotificationDelivery $delivery, array $config): DeliveryResult;
    /** Send a test message. $config is already decrypted. */
    public function test(array $config): DeliveryResult;
    /** Throw \InvalidArgumentException if config is invalid. */
    public function validateConfig(array $config): void;
    /** Parse inbound payload into AckResult. Return null if not applicable. */
    public function parseInboundAck(array $payload): ?AckResult;
}

Credential Storage

Credentials are stored in transport_channels.config as a JSON blob encrypted at rest using libsodium. The transport handler receives the decrypted config array at send time. Credentials are never logged or returned in API responses.

Three-Level Config Hierarchy

Level	Where stored	Who controls
Platform defaults	transport_types.platform_config	superadmin
Per-channel config	transport_channels.config	agency admin
Per-user overrides	user_transport_preferences.config_override	company user

All three levels are encrypted.

Adding a Custom Transport

1. Create a class in cloud/src/Transport/ implementing TransportHandlerInterface
2. Tag the service with psaplink.transport
3. Add credentials schema to the transport registry
4. Add a doc page in this section