From c68fab6c3137ddfd88fbad987f119e30e2550981 Mon Sep 17 00:00:00 2001
From: Shahbaz Nazir <shahbazn@users.noreply.github.com>
Date: Thu, 13 Sep 2018 16:03:22 +0200
Subject: [PATCH] Problem: A duplicate tx may result in HTTP 500.

* Improve parsing of errors received from Tendermint RPC.
---
 bigchaindb/lib.py | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/bigchaindb/lib.py b/bigchaindb/lib.py
index f6761aa6..2dadcb90 100644
--- a/bigchaindb/lib.py
+++ b/bigchaindb/lib.py
@@ -100,7 +100,14 @@ class BigchainDB(object):
 
         error = response.get('error')
         if error:
-            return (500, error)
+            status_code = 500
+            message = error.get('message', 'Internal Error')
+            data = error.get('data', '')
+
+            if 'Tx already exists in cache' in data:
+                status_code = 400
+
+            return (status_code, message + ' - ' + data)
 
         result = response['result']
         if mode == self.mode_commit: