The strata server can indicate an error to the client either as HTTP error codes and/or STRATA_CODE headers, and both of these can additionally have either a STRATA_MESSAGE header and/or a response body containing the error message.  The response body can be XML or HTML (or potentially Text), the STRATA_MESSAGE will be XML.

Additionally, responses from the strata client library are not exclusively either success or failure, a response can indicate some combination of success and failure.  A single 'action' on the part of the client, for example creating a case, can involve multiple interactions with the server, POST to create the case, and one or more POSTs to attach files.  If for example, the case creation POST succeeds, but one of the attach POSTs fails, then the response must clearly indicate both.

Whatever the response(s) from the strata server, theses need to be converted to a single 'text' (optionally with an additional URL) response message for display by the report library.  The HTML and XML need to be converted to text, either by 'formatting' it, or by ignoring it, and mapping the codes to error messages.

Advice from the Strata Server developer, Tim Walsh was:
For the time being just read the STRATA_CODE and STRATA_MESSAGE headers and if there is an error condition then skip the body.