Webhooks

Callbacks

A callback is an HTTP POST request with a notification made by the Sinch SMS REST API to a URI of your choosing.

The REST API expects the receiving server to respond with a response code within the 2xx success range. For 5xx the callback will be retried. For 429 the callback will be retried and the throughput will be lowered. For other status codes in the 4xx range the callback will not be retried. The first initial retry will happen 5 seconds after the first try. The next attempt is after 10 seconds, then after 20 seconds, after 40 seconds, after 80 seconds, doubling on every attempt. The last retry will be at 81920 seconds (or 22 hours 45 minutes) after the initial failed attempt.

Note that, with these callbacks, the Sinch SMS REST API will make a request to the URI of your choosing. This means that Sinch will be authenticating against your system. By making a request to your account manager, SMS REST API callbacks may be configured with the following options:

Basic authentication is the simplest form of authentication. It enables access to the SMS API via a username and password. Basic Auth can be utilised in a callback by provisioning the callback URL with the appropriate username and password. Note that, because callbacks are made by Sinch to a URI of your choosing (rather than a call made by your system to Sinch's endpoints), the username and password must be accepted by your system.
OAuth 2.0 is a standard form of authentication that provides enhanced security when compared to Basic Authentication. It uses access tokens to reduce the risk of credentials being intercepted. OAuth 2.0 can be utilised in a callback by provisioning the callback URL with username, password and the URL to fetch OAuth access token. Note that, because callbacks are made by Sinch to a URI of your choosing (rather than a call made by your system to Sinch's endpoints), the username, password, and and access token URL must be accepted by your system.
HMAC Hash-based message authentication code. It is a cryptographic authentication technique that uses a hash function and a secret key. HMAC can also be configured alongside Basic Auth and OAuth.
AWS SNS is a managed service that provides message delivery from publishers to subscribers by routing messages through SNS topics. Users can utilise AWS SNS in a callback by provisioning the callback URL with an Access Key ID, Secret Key and Region.

Incoming SMSWebhook

An inbound message is a message sent to one of your short codes or long numbers from a mobile phone. To receive inbound message callbacks, a URL needs to be added to your REST API. This URL can be specified in your Dashboard.

Request

Request Body schema: application/json

The incoming message to your sinch number

One of:

The page of inbounds matching the given filters.

body required	string [ 0 .. 2000 ] characters
from required	string The phone number that sent the message. More info
id required	string The ID of this inbound message.
received_at required	string <date-time> When the system received the message. Formatted as ISO-8601: `YYYY-MM-DDThh:mm:ss.SSSZ`.
to required	string The Sinch phone number or short code to which the message was sent.
type required	string Regular SMS Value: "mo_text"
client_reference	string If this inbound message is in response to a previously sent message that contained a client reference, then this field contains that client reference. Utilizing this feature requires additional setup on your account. Contact your account manager to enable this feature.
operator_id	string The MCC/MNC of the sender's operator if known.
sent_at	string <date-time> When the message left the originating device. Only available if provided by operator. Formatted as ISO-8601: `YYYY-MM-DDThh:mm:ss.SSSZ`.

Responses

200

A 2xx status code indicates that the data was received successfully.

400

A 4xx status counts as a permanent failure and will not trigger any retries, except for 429.

429

The callback will be retried and the callback throughput will be lowered.

500

A 5xx status code will trigger a retry.

Request samples

Payload

application/json

{"body": "This is a test message.",
"from": "16051234567",
"id": "01XXXXX21XXXXX119Z8P1XXXXX",
"operator_id": "string",
"received_at": "2022-08-24T14:15:22Z",
"sent_at": "2022-08-24T14:15:22Z",
"to": "13185551234",
"type": "mo_text"
}

Delivery ReportWebhook

A delivery report contains the status and status code for each recipient of a batch. To get a delivery report callback for a message or batch of messages, set the delivery_report field accordingly when creating a batch.

The following is provided so you can better understand our webhooks/callbacks. Configuration of both webhooks and the type of delivery report requested happens when sending a batch.

Callback URL

The callback URL can either be provided for each batch or provisioned globally for your account in your Sinch Customer Dashboard. Learn how to configure a webhook/callback here.

Type

The type is the type of delivery report webhook. The response will vary depending on the webhook delivery report you selected when the batch was sent, so choose the appropriate selection under "One of".

The delivery_report_sms and delivery_report_mms types are documented under Delivery report. These are reports containing either a full report or summary report, depending on your selection at the time the batch was sent.
The recipient_delivery_report_sms and recipient_delivery_report_mms delivery report types are documented under Recipient delivery report. These are delivery reports for recipient phone numbers. If you set per_recipient for the delivery_report parameter when sending the batch, a recipient report gets sent to you for each status change for each recipient in your batch. If you set per_recipient_final, a recipient report gets sent to you for the final status of each recipient in your batch.