MySMSAPio — SMS Gateway API

Getting Started

The MySMSAPio API is a JSON REST API. There are two classes of consumer:

Client applications — send SMS, generate/verify OTPs, read inbound messages, and query admin stats. Authenticated with a api_live_… key.
Gateway devices — Android phones that register, send heartbeats, report inbound SMS and delivery receipts. Authenticated with a gw_live_… key.

Base URL

https://your-host/api/v1

Content-Type

application/json

Authentication

All authenticated endpoints expect an API key in the Authorization header as a Bearer token. Keys are SHA-256 hashed at rest — the raw key is only shown once at creation.

Client key

api_live_<64 hex chars>

Permissions-based (send_sms, receive_sms…). Can expire.

Gateway key

gw_live_<64 hex chars>

Bound to a single gateway device. Must be active.

# Bearer token in the Authorization header

curl https://your-host/api/v1/sms/received \

  -H "Authorization: Bearer api_live_..."

Rate Limits

Limits are enforced via Redis and return 429 Too Many Requests with a retry_after hint.

Resource	Limit	Window
Send SMS	100	per minute / API key
Send OTP	3	per hour / phone number
OTP verify attempts	3	per code

Error Codes

Errors are returned as JSON with an error field. Validation errors also include details.

Status	Meaning
400	Bad Request — missing required parameter
401	Unauthorized — missing or invalid API key
403	Forbidden — insufficient permissions
404	Not Found — resource does not exist
409	Conflict — e.g. gateway already registered
422	Unprocessable Entity — validation failure
429	Too Many Requests — rate limit exceeded
500	Internal Server Error

POST /sms/send

Send an SMS

Queues an outbound message. The API returns immediately with a message_id; delivery happens asynchronously via an available gateway. Rate limited to 100/min per API key.

Request body

Parameter	Type	Required	Description
to	string	yes	E.164 phone number (validated via Phonelib)
message	string	yes	Message body (max 1600 chars)

Example request

curl -X POST https://your-host/api/v1/sms/send \

  -H "Authorization: Bearer api_live_..." \

  -H "Content-Type: application/json" \

  -d '{"to":"+14155551234","message":"Your code is 482915"}'

Response · 202 Accepted

{

  "success": true,

  "message_id": "msg_3f8a9c1b2e7d4f60",

  "status": "queued"

}

GET /sms/status/:message_id

Check SMS Status

Returns the current lifecycle state of a message, including timestamps.

Path parameters

Parameter	Type	Description
message_id	string	The ID returned when the message was created

Response · 200 OK

{

  "message_id": "msg_3f8a9c1b2e7d4f60",

  "status": "delivered",

  "sent_at": "2026-08-01T12:00:00Z",

  "delivered_at": "2026-08-01T12:00:03Z",

  "failed_at": null,

  "error_message": null

}

Statuses: queued → pending → sent → delivered | failed

GET /sms/received

List Received SMS

Paginated list of inbound messages, newest first. Optional filters by phone number or date.

Query parameters

Parameter	Type	Default	Description
phone_number	string	—	Filter by sender phone
since	datetime	—	Only messages after this time
limit	integer	50	Items per page

Response · 200 OK

{

  "messages": [

    {

      "message_id": "msg_7a2f...",

      "from": "+14155559999",

      "message": "STOP",

      "received_at": "2026-08-01T12:05:00Z"

    }

  ],

  "total": 1,

  "page": 1,

  "pages": 1

}

POST /otp/send

Send an OTP

Generates a 6-digit code, sends it via SMS, and returns the expiry time. Max 3 codes per phone per hour.

Request body

Parameter	Type	Required	Default
phone_number	string	yes	—
purpose	string	no	authentication
expiry_minutes	integer	no	5

Response · 200 OK

{

  "success": true,

  "expires_at": "2026-08-01T12:10:00Z",

  "message_id": "msg_9b1c..."

}

POST /otp/verify

Verify an OTP

Validates the 6-digit code. After 3 failed attempts the code is expired. On success the code is marked verified and cannot be reused.

Request body

Parameter	Type	Required
phone_number	string	yes
code	string	yes

Success · 200

{

  "success": true,

  "verified": true

}

Failure · 200

{

  "success": false,

  "verified": false,

  "error": "Invalid or expired OTP",

  "attempts_remaining": 2

}

GET /admin/stats

Admin Statistics

Aggregate system metrics: gateway counts, message throughput, pending/failed counts, and OTP performance for today.

Response · 200 OK

{

  "gateways": { "total": 4, "active": 3, "online": 2, "offline": 2 },

  "messages": {

    "total_sent": 10234, "total_received": 8821,

    "sent_today": 142, "received_today": 98,

    "total_today": 240, "pending": 3, "failed_today": 1

  },

  "otp": { "sent_today": 56, "verified_today": 49, "verification_rate": 87.5 },

  "timestamp": "2026-08-01T12:00:00Z"

}

GET /admin/gateways

List Gateways

Returns every registered gateway device with live status and counters.

POST /admin/gateways/:id/toggle

Activate or deactivate a gateway. Toggling off stops it from receiving outbound commands.

Toggle response · 200 OK

{

  "success": true,

  "gateway": { "id": 1, "device_id": "pixel-001", "active": false }

}

POST /gateway/register

Register a Gateway

No auth Registers an Android device and returns a fresh gateway API key. Returns 409 if the device_id already exists.

Request body

Parameter	Type	Required	Description
device_id	string	yes	Unique device identifier
name	string	no	Friendly name (defaults to device id prefix)

Response · 201 Created

{

  "success": true,

  "api_key": "gw_live_a1b2c3...",

  "device_id": "pixel-001",

  "websocket_url": "wss://your-host/cable"

}

Save api_key immediately — it is never shown again.

POST /gateway/heartbeat

Gateway Heartbeat

Refreshes the gateway's online status. A gateway is marked offline if no heartbeat arrives within 2 minutes (handled by CheckGatewayHealthJob).

Optional body

Parameter	Type	Description
battery_level	integer	0–100
signal_strength	integer	dBm
messages_in_queue	integer	Pending outbound count on device

Response · 200 OK

{ "success": true, "pending_messages": 3 }

POST /gateway/sms/received

Report Inbound SMS

Called by the gateway when a new SMS arrives on the device. Creates an inbound record and triggers ProcessInboundSmsJob (which fires webhooks).

Request body

Parameter	Type	Required
sender	string	yes
message	string	yes
timestamp	datetime	no

Response · 200 OK

{ "success": true, "message_id": "msg_7a2f..." }

POST /gateway/sms/status

Report Delivery Status

Updates an outbound message's status. On failed, RetryFailedSmsJob is enqueued if retries remain (< 3).

Request body

Parameter	Type	Required	Values
message_id	string	yes	—
status	string	yes	sent · delivered · failed
error_message	string	no	Reason for failure

Response · 200 OK

{ "success": true }

WS /cable

WebSocket Channel

Gateways maintain a persistent Action Cable connection for real-time command dispatch and status reporting. Connections authenticate with the gateway API key as a query param.

Connect

wscat -c "wss://your-host/cable?api_key=gw_live_..."

Server → Gateway commands

{

  "action": "send_sms",

  "message_id": "msg_3f8a...",

  "recipient": "+14155551234",

  "message": "Hello!"

}

Gateway → Server events

action	Payload
heartbeat	battery_level, signal_strength, messages_in_queue
delivery_report	message_id, status, error_message
message_received	sender, message, timestamp

WEBHOOK Outbound HTTP POST

Webhooks

When configured, the API delivers signed event payloads to your URL via TriggerWebhookJob. If a secret key is set, each request is signed with HMAC-SHA256.

sms_received

Inbound SMS arrived

sms_sent

Message dispatched to gateway

sms_failed

Delivery failed

Example payload (sms_received)

{

  "event": "sms_received",

  "message_id": "msg_7a2f...",

  "from": "+14155559999",

  "message": "Confirm",

  "received_at": "2026-08-01T12:05:00Z"

}

Verifying the signature

# Ruby

signature = OpenSSL::HMAC.hexdigest("SHA256", secret_key, payload.to_json)

# Compare with the X-Webhook-Signature header

API Documentation

Getting Started

Authentication

Rate Limits

Error Codes

Send an SMS

Check SMS Status

List Received SMS

Send an OTP

Verify an OTP

Admin Statistics

List Gateways

Register a Gateway

Gateway Heartbeat

Report Inbound SMS

Report Delivery Status

WebSocket Channel

Webhooks