TOSCA – Heat ideas and standards
Topology and Orchestration Specification for Cloud Applications (TOSCA) has emerged as a standard orchestration and deployment framework for cloud systems. This standard has been adopted by OpenStack for their orchestration project named Heat. Heat fully supports TOSCA and offers features for materializing the design topology and dynamically scales resources according to the requirements of the applications.
Heat supports text files called templates for describing cloud infrastructure or the applications composing the cloud. The cloud infrastructure or bundle of components composing the cloud is called stack in the Heat terminology. The template format supported by Heat is the same as the AWS CloudFormation template. Heat supports the OpenStack native REST API (HOT) as well as the CloudFormation compatible query API.
Using Heat templates, resource types can be defined, which include instances, floating IPs, volumes...