code: function update(req, res, next) {
    var submission = req.body || {};
    submission.submissionId = req.params.id;
    //note this is a work around for submissions which exist in beta before the update to widg guids was done
    if (!submission.appClientId) {
      submission.appClientId = submission.appId;
    }
    var params = {
      submission: submission,
      skipValidation: true
    };
  
    logger.debug("Middleware Submissions Update ", {params: params});
  
    forms.updateSubmission(_.extend(req.connectionOptions, params), submissionsHandler(constants.resultTypes.submissions, req, next));
  }
docs: Get A Single Submission
  @param req
  @param res
  @param next