Allow setting the value of saml2:Issuer

[candrews]

I'd like to have a way to set the value of the saml2:Issuer in saml2p:AuthnRequest (the IdP I'm using requires it to have a specific value). However, it is currently being set the entityId and there is no way (at least, that I can see, to change it.)

[ulisesbocchio]

alright, let me dig into this and will come back to you with either an existing way for you to set it, or expose a way if it's not there.

[candrews]

Looks like the IdP I'm using isn't the only one that requires a specific value for the Issuer - Azure AD also has a requirement on it: https://docs.microsoft.com/en-us/azure/active-directory/develop/active-directory-single-sign-on-protocol-reference

[candrews]

A workaround is to define a bean like this:

    @Bean
    public WebSSOProfile myWebSSOProfile(){
	   return new DSLWebSSOProfileImpl() {

	    	@Override
	    	protected Issuer getIssuer(String localEntityId) {
	    		return super.getIssuer("SOME VALUE HERE");
	    	}

			@Override
			public void afterPropertiesSet() throws Exception {
				// this override can be removed after https://github.com/ulisesbocchio/spring-boot-security-saml/pull/58
			}

	    };
    }