Problems getting a new Idp talking to testshib

[Brad Larson]

I apologize if the answer here is obvious, I can't find anything.

I'm trying to set up an Idp and test it with testshib.  I haven't
configured any user authentication yet.

My Idp is giving me an error:

WARN [edu.internet2.middleware.shibboleth.idp.profile.saml2.SSOProfileHandler:373]
- Error decoding authentication request message
org.opensaml.ws.message.decoder.MessageDecodingException: No
SAMLRequest or SAMLResponse query path parameter, invalid SAML 2 HTTP
Redirect message

One possible issue I'm not sure about - I might not have the SOAP
endpoints configured correctly
(https://wiki.shibboleth.net/confluence/display/SHIB2/IdPApacheTomcatPrepare).
 Could that be related?  I couldn't determine from the docs if I
should have my user-facing Idp without clientAuth and the SOAP portion
with clientAuth on the same port (or how that would even be
possible...), but I assume they both must be on 443?

Many thanks for any and all help,
Brad