cli: /payments: respond peer offline as E409

This was not catched because the SDK does minimal handling of PFS
errors, preferring passing them through directly as promise's rejection
error. We catch this specific error literally, and return a 409 response
now, in line with PC's behavior

Author: andrevmatos

raiden-cli/src/routes/payments.ts

@@ -47,7 +47,7 @@ function transformSdkTransferToApiPayment(transfer: RaidenTransfer): ApiPayment
   };
 }
 
-function isConflictError(error: unknown): error is RaidenError {
+function isTransferConflictError(error: unknown): error is RaidenError {
   return [
     ErrorCodes.PFS_INVALID_INFO,
     ErrorCodes.PFS_NO_ROUTES_FOUND,
@@ -59,6 +59,8 @@ function isConflictError(error: unknown): error is RaidenError {
     ErrorCodes.PFS_LAST_IOU_REQUEST_FAILED,
     ErrorCodes.PFS_IOU_SIGNATURE_MISMATCH,
     ErrorCodes.PFS_NO_ROUTES_BETWEEN_NODES,
+    // PFS errors are passed through by the SDK, so we need to test literally
+    'There is no user found online for given address.',
   ].includes((error as Error).message);
 }
 
@@ -102,10 +104,8 @@ async function doTransfer(this: Cli, request: Request, response: Response, next:
       response.status(402).send(error.message);
     } else if (isTransferFailedError(error)) {
       response.status(409).send(error.message);
-    } else if (isConflictError(error)) {
-      const errors = (error.details as { errors: string } | undefined)?.errors;
-      const pfsErrorDetail = errors ? ` (${errors})` : '';
-      response.status(409).json({ message: error.message, details: pfsErrorDetail });
+    } else if (isTransferConflictError(error)) {
+      response.status(409).json({ message: error.message, details: error.details });
     } else {
       next(error);
     }