Appery.io API Express comes with a visual service editor which allows to create advanced service logic. For example, you can create a REST API where you invoke a SOAP service, and connect to an external SQL database. Combining the result from both services in a logic way and making it the service response. This video shows how to connect to an external REST API.
API used in this video: http://services.faa.gov/docs/services/airport/
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