Virtual Services (REST)
Use this editor to create and modify REST-based virtual services. Virtual services handle requests in the inbound processing scenario. When a SaaS application sends a service request, a virtual service performs security checks and other user-defined processing before sending the request to the on-premise application.
A virtual service runs on CloudStreams and acts as the consumer-facing proxy for a native service running in an on-premise application. A virtual service provides a layer of abstraction between the service consumer and the service provider, and promotes loose coupling by providing independence (of location, protocol and format) between the consuming application and the provider service. You should create a virtual service for each native service you want to expose to consumers.
When you create a virtual service, you can configure the following processing steps for the service:
The
In Sequence step, which you configure to manipulate the request messages. This step can include the following sub-steps:
The
Entry step (provided by default), which specifies the protocol (HTTP or HTTPS) of the requests that the virtual service will accept. You also specify the REST resource that the service will access and the HTTP methods (GET, POST, PUT and DELETE) that the virtual service should be allowed to perform on the REST resource.
The
Transform step (optional), which performs an XSLT message transformation on the request message before the virtual service submits it to the native service.
The
Invoke IS Service step (optional), which pre-processes the request message before the virtual service submits it to the native service.
The
Routing Rule step (provided by default), which specifies how the virtual service will route the requests to the native service endpoint. There are four ways to route HTTP or HTTPS requests:
Straight Through routing (to route requests directly to the native service endpoint).
Context-Based routing (to route specific types of messages to specific endpoints according to context-based routing rules).
Content-Based routing (to route specific types of messages to specific endpoints based on specific values that appear in the request message).
Load Balancing routing (to distribute requests among multiple endpoints).
The service's
Out Sequence step, which you configure to manipulate the response messages. This step can include the following sub-steps:
The
Transform step (optional), which specifies how the response message from the native service provider is to be transformed before the virtual service returns it to the consuming application.
The
Invoke IS Service step step (optional), which pre-processes the response message before the virtual service returns it to the consuming application.
The service's
Error Sequence step (provided by default).
CloudStreams returns a default fault response to the consuming application, which you can customize with context variables. This fault response is used for faults returned by the native service provider as well as faults returned by internal
CloudStreams exceptions (policy violation errors, cloud connection errors and cloud connector service errors). In addition, you can:
Choose whether or not to send the native service provider's service fault content, or just send the response message.
Invoke IS services to pre-process or post-process the error messages.