seahaven-door-unlock-api/README.md

Sea Haven Door Unlock API

AWS Lambda middleware that allows a Yealink T54W desk phone to unlock the front door controlled by LenelS2 Elements. Press a DSS key on the phone, and the door unlocks.

Yealink T54W → HTTPS GET → API Gateway → Lambda → LenelS2 Elements API → Door Unlocks

Architecture

• API Gateway (HTTP API) — single GET /unlock endpoint with throttling (5 burst / 2 sustained req/sec)
• Lambda (Node.js 20.x) — validates a shared auth token, calls the Elements TemporaryUnlock command
• SSM Parameter Store — stores the Elements API key, auth token, and door device ID
• Custom Domain — doorunlock.seahaven.com via Route 53 + ACM wildcard cert

SSM Parameters

Parameter	Type	Description
/seahaven/door-unlock/elements-api-key	SecureString	LenelS2 Elements API key
/seahaven/door-unlock/auth-token	SecureString	Shared secret embedded in the Yealink DSS key URL
/seahaven/door-unlock/door-id	String	Elements device ID for the front door reader

Deployment

npm install
npx cdk deploy

Phone Configuration

Configure a DSS key on the Yealink T54W (via phone web UI or 3CX):

• Type: URL
• Label: Unlock Door
• Value: https://doorunlock.seahaven.com/unlock?token=<auth-token-value>

3CX Provisioning Templates

Two custom 3CX templates for the Yealink T54W are included. Both have the door unlock URL hardcoded on line key 2.

Template	Line Key 2	Keys 3-5	Display
yealinkT54W-door-unlock.ph.xml	Unlock Door	Managed by 3CX BLF	Dim after 5 min, never sleep
yealinkT54W-door-unlock-with-sp.ph.xml	Unlock Door	Shared Parking SP1-3	Dim after 5 min, never sleep