better logging in failure scenarios

Signed-off-by: Travis Glenn Hansen <travisghansen@yahoo.com>

bin/democratic-csi

@@ -194,6 +194,9 @@ async function requestHandlerProxy(call, callback, serviceMethodName) {
     let message;
     if (e instanceof Error) {
       message = e.toString();
+      if (e.stack) {
+        message += ` ${e.stack}`;
+      }
     } else {
       message = JSON.stringify(e);
     }

src/driver/controller-zfs-generic/index.js

@@ -406,7 +406,7 @@ delete ${iscsiName}
       options
     );
     if (response.code != 0) {
-      throw new Error(response.stderr);
+      throw new Error(JSON.stringify(response));
     }
     driver.ctx.logger.verbose(
       "TargetCLI response: " + JSON.stringify(response)