RelyingPartyConfigurationManager creation failed: IllegalArgumentException: Host name may not be null

[Cantor, Scott]

> Attached is my SP metadata file. Note this file was generated by the
> spring-security-saml2-core codebase.

Has nothing to do with the metadata.

> What could be causing this problem? Is it because of localhost being
> used in the file instead of FQDN?

No, it's an error in a URL parameter supplied to the metadata provider in the IdP.

-- Scott