Send transactional emails from Salesforce Marketing Cloud through its REST API, from any external tool such as SOAP UI or Postman.

Authenticate with the client credentials of an API Integration package to get an access token, then call the transactional messaging endpoint of your instance.

Preparation

Create client id & secret on Installed Packages>Components “API Integration” /cloud/#app/Setup/InstalledPackages.

Walkthrough

Get token

Create a request with the client id & secret from the preparation, endpoint https://xxx.auth.marketingcloudapis.com/v2/token and the following body:

{
  "grant_type": "client_credentials",
  "client_id": "[client id]",
  "client_secret": "[client secret]",
  "scope": "email_read email_write email_send",
  "account_id": "[account id]"
}

Response:

{
  "access_token": "eyJhbGciOiJIUzI1NiIsxxx",
  "token_type": "Bearer",
  "expires_in": 1079,
  "scope": "email_read email_write email_send",
  "soap_instance_url": "https://xxx.soap.marketingcloudapis.com/",
  "rest_instance_url": "https://xxx.rest.marketingcloudapis.com/"
}

REST Call

  1. Create another request with the endpoint set as the previous rest_instance_url
  2. Use below request with endpoint [rest_instance_url]messaging/v1/email/messages/ 
{
  "definitionKey": "[transactionalDefKey]",
  "recipients": [
    {
      "contactKey": "[contactId]",
      "to": "[contactEmail]",
      "attributes": {
        "FirstName": "John",
        "LastName": "Doe"
      }
    }
  ]
}

Response:

{
  "requestId": "xxx",
  "errorcode": 0,
  "responses": [
    {
      "messageKey": "xxx"
    }
  ]
}

Going further