I've been trying to integrate SAML with WSO2 cloud.
I have some successful experience with other vendors like onelogin, okta, ping one.

But I get a obscure 500 error with wso2.
I get a 500 error with every request I try.

I don't need much - just a SAMLRequest format that will work for WSO2.
For example, now I'm passing:

```
<?xml version="1.0" encoding="UTF-8"?>
<saml2p:AuthnRequest ID="z9dac5520-d4a4-4da9-b71a-483948c1655c" IssueInstant="2017-04-29T08:40:39.677Z" ProtocolBinding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST" Version="2.0" xmlns:saml2p="urn:oasis:names:tc:SAML:2.0:protocol">
<saml2:Issuer xmlns:saml2="urn:oasis:names:tc:SAML:2.0:assertion"/>
<saml2p:NameIDPolicy Format="urn:oasis:names:tc:SAML:1.1:nameid-format:unspecified"/>
</saml2p:AuthnRequest>

```

I defalate, base 64 encode and url encode it.

I tried different variations but nothing works

thanks