White-label your customer's email domain
In addition to white-labeling the branding of their emails, some Courier customers want to white-label the email sender domain for their users.
Courier allows you to do this by sending emails using your customer's Email Service Provider. This is accomplished by overriding the API key of your email provider integration with your customer's provider API key.
Overriding the email integration API key
To send with your customer's email service provider, you'll need your customer's Email Service Provider API Key.
Add an integration in your Courier Tenant for each Email Service Provider you'd like to support*
Add those integrations to the email channel of the notification template you want to white-label
Use provider-level conditions to determine which provider gets used (e.g. send over a data field named "esp" with the value "mailgun" and set a rule that only enables that provider if that value has been set).
Provide your customer's API key using the override** section of the send command.
*Note: the initial API key you put into the Courier email integrations don't need to be valid as long as you're always going to override the API Key via the Send API.
**See the Override section of your provider's Courier integration doc for details.
Sending with your Customer's From: email address
To programmatically set the From: address on an email template, you'll use a variable in the email channel settings as detailed in this help doc: Setting the from, reply to, cc and bcc names and address fields.