It may be that the import of the YAML file fails or the REST service provides no description file at all. In this case, you can draw the REST interface definitions manually. On REST Import Rules you can find an overview on how OpenAPI entities are mapped to UML elements.

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Add a REST alias to your component diagram. How to manually create an alias is described on Backend Components > Creating an Alias. Apply stereotype <<RESTAlias>> and provide the necessary tagged values as described on REST Adapter Reference > <<RESTAlias>>. 

API Classes

Collect all parameter and type information from the REST API documentation, draw the necessary classes and their relations. If you have an XML Schema (XSD) of the classes, you can import the XSD. The E2E REST Importer would import the type information to a package <your API name>/Types and we recommend to do the same.

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Defining a REST interface to access a REST service with the REST Adapter resembles defining the interface of a REST service itself. You can find more information on that on Defining a REST Service Interface. You need to create all service elements that are listed as mandatory in the table below.
A REST interface consists of:

Element	Stereotype	Mandatory	Tagged Values Reference Link
a REST interface UML package	<<RESTInterface>>		<<RESTInterface>>
REST resource classes	<<RESTResource>>		<<RESTResource>>
REST operations	<<REST>>		<<REST>>
REST parameters	<<RESTParameter>>	()	<<RESTParameter>>
REST error class(es)	<<RESTError>>		<<RESTError>>
REST response definitions	<<RESTResponseDefinition>>		<<RESTResponseDefinition>>

REST interface documentation and tags as described on Defining a REST Service Interface are not relevant in this case and you can leave them out.

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