I'm using Mandrill to send emails from my Rails 3 application. In production, I use the API key I set up in their admin console. To prevent dev and test SNAFUs that might email all our users, I've put garbage keys in the development and test environment config and I only put the real key in the production config. Mandrill allows you to create multiple API keys. Does anyone know if there's a way to configure Mandrill such that an API call to send an email using the development or test key will fail unless a certain precondition is met (e.g. email domain matches mycompany.com)?
Mandrill API keys all function the same and have full access for all API calls in the account. There's not currently a concept of a development, sandbox or test key, or scoping API keys. However, test mode/functionality is on the development roadmap. I don't currently have an ETA, but it's definitely something we're working on.
EDITED TO ADD: As of the time of this answer originally, this wasn't possible. Mandrill does now have a test mode.