Sending LIS Outcome to Desire2Learn

Question

I'm building an LTI tool that will allow users to be graded on content they create in my system. I want to accomplish this through LIS Outcomes, but I'm having trouble sending my grade to the D2L system.

I keep getting an "Exception Occurred while processing the request" message from D2L.

Am I sending the correct request body?

Here is the request body I am sending:

<?xml version="1.0" encoding="UTF-8"?>
<imsx_POXEnvelopeRequest xmlns="http://www.imsglobal.org/services/ltiv1p1/xsd/imsoms_v1p0">
  <imsx_POXHeader>
    <imsx_POXRequestHeaderInfo>
      <imsx_version>V1.0</imsx_version>
      <imsx_messageIdentifier>Inserted from My App</imsx_messageIdentifier>
    </imsx_POXRequestHeaderInfo>
  </imsx_POXHeader>
  <imsx_POXBody>
    <replaceResultRequest>
      <resultRecord>
        <sourcedGUID>
          <sourcedId>31e08aaa-157f-4f60-9b7f-65c4f6f8ae67</sourcedId>
        </sourcedGUID>
        <result>
          <resultScore>
            <language>en</language>
            <textString>0.65</textString>
          </resultScore>
        </result>
      </resultRecord>
    </replaceResultRequest>
  </imsx_POXBody>
</imsx_POXEnvelopeRequest>

And here is the response I get back from the D2L server:

<?xml version="1.0" encoding="UTF-8"?>
<imsx_POXEnvelopeRequest xmlns="http://www.imsglobal.org/services/ltiv1p1/xsd/imsoms_v1p0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <imsx_POXHeader>
    <imsx_POXResponseHeaderInfo>
      <imsx_version>V1.0</imsx_version>
      <imsx_messageIdentifier>Inserted from My App</imsx_messageIdentifier>
      <imsx_statusInfo>
        <imsx_codeMajor>failure</imsx_codeMajor>
        <imsx_severity>error</imsx_severity>
        <imsx_description>Exception occured while processing the request.</imsx_description>
        <imsx_messageRefIdentifier>11a1fe65-aacf-47d6-9062-072cb61cc5b4</imsx_messageRefIdentifier>
        <imsx_operationRefIdentifier>replaceResult</imsx_operationRefIdentifier>
      </imsx_statusInfo>
    </imsx_POXResponseHeaderInfo>
  </imsx_POXHeader>
  <imsx_POXBody />
</imsx_POXEnvelopeRequest>

Any help is greatly appreciated, thanks.

Edit: As a sidenote, I was at first sending the Oauth hash in the Authorization header with spaces in between values.

for example: Authorization: OAuth realm="{url}", oauth_signature="{sig}"...

but I kept getting a "authorizationfailure" message.

I took a look at the PHP example at: https://github.com/Desire2Learn-Valence/sample-LTI-WHMIS-quiz, and it looked like that was not inserting the spaces into the Authorization header, so i changed my headers to look like:

Authorization: OAuth realm="{url}",oauth_signature="{sig}"

And now D2L seems to accept it, but gives me the aforementioned Exception occured message