idpSSOInit.jsp initiates single sign-on from the identity provider side (also referred to as unsolicited response). For example, a user requests access to a resource. On receiving this request for access, idpSSOInit.jsp looks for a cached assertion which, if present, is sent to the service provider in an unsolicited <Response>. If no assertion is found, idpSSOInit.jsp verifies that the following required parameters are defined:
metaAlias: This parameter takes as a value the metaAlias set in the identity provider's extended metadata configuration file. If the metaAlias attribute is not present, an error is returned.
spEntityID: The entity identifier of the service provider to which the response is sent.
If defined, the unsolicited Response is created and sent to the service provider. If not, an error is returned. The endpoint for this JSP is protocol://host:port/service-deploy-uri/idpssoinit. The following optional parameters can also be passed to idpSSOInit.jsp: