From 22678e38385abcaf6948287eea4e7eb791002fa7 Mon Sep 17 00:00:00 2001
From: Chris Kleeschulte <chrisk@bitpay.com>
Date: Tue, 17 Oct 2017 14:23:51 -0400
Subject: [PATCH] Added tx cache.

---
 errors.txt                        | 16 ++++++++++++++++
 lib/services/transaction/index.js | 19 ++++++++++++++++++-
 2 files changed, 34 insertions(+), 1 deletion(-)
 create mode 100644 errors.txt

diff --git a/errors.txt b/errors.txt
new file mode 100644
index 00000000..3f7ba46c
--- /dev/null
+++ b/errors.txt
@@ -0,0 +1,16 @@
+17-10-16T23:06:28.131Z] error: Error: Block hash or address expected
+Oct 16 23:06:28 rs-iad-insight-04 bitcored[23072]:     at TxController.list (/home/bitcore/.npm-packages/lib/node_modules/bitcore/node_modules/insight-api/lib/transactions.js:321:37)
+Oct 16 23:06:28 rs-iad-insight-04 bitcored[23072]:     at Layer.handle [as handle_request] (/home/bitcore/.npm-packages/lib/node_modules/bitcore/node_modules/express/lib/router/layer.js:95:5)
+Oct 16 23:06:28 rs-iad-insight-04 bitcored[23072]:     at next (/home/bitcore/.npm-packages/lib/node_modules/bitcore/node_modules/express/lib/router/route.js:137:13)
+Oct 16 23:06:28 rs-iad-insight-04 bitcored[23072]:     at /home/bitcore/.npm-packages/lib/node_modules/bitcore/node_modules/insight-api/lib/index.js:73:5
+Oct 16 23:06:28 rs-iad-insight-04 bitcored[23072]:     at Layer.handle [as handle_request] (/home/bitcore/.npm-packages/lib/node_modules/bitcore/node_modules/express/lib/router/layer.js:95:5)
+Oct 16 23:06:28 rs-iad-insight-04 bitcored[23072]:     at next (/home/bitcore/.npm-packages/lib/node_modules/bitcore/node_modules/express/lib/router/route.js:137:13)
+Oct 16 23:06:28 rs-iad-insight-04 bitcored[23072]:     at Route.dispatch (/home/bitcore/.npm-packages/lib/node_modules/bitcore/node_modules/express/lib/router/route.js:112:3)
+Oct 16 23:06:28 rs-iad-insight-04 bitcored[23072]:     at Layer.handle [as handle_request] (/home/bitcore/.npm-packages/lib/node_modules/bitcore/node_modules/express/lib/router/layer.js:95:5)
+Oct 16 23:06:28 rs-iad-insight-04 bitcored[23072]:     at /home/bitcore/.npm-packages/lib/node_modules/bitcore/node_modules/express/lib/router/index.js:281:22
+Oct 16 23:06:28 rs-iad-insight-04 bitcored[23072]:     at
+
+
+
+17
+
diff --git a/lib/services/transaction/index.js b/lib/services/transaction/index.js
index 19d0fdec..a6ef3551 100644
--- a/lib/services/transaction/index.js
+++ b/lib/services/transaction/index.js
@@ -6,6 +6,7 @@ var Encoding = require('./encoding');
 var _ = require('lodash');
 var async = require('async');
 var assert = require('assert');
+var LRU = require('lru-cache');
 
 function TransactionService(options) {
   BaseService.call(this, options);
@@ -24,6 +25,9 @@ function TransactionService(options) {
   if (this._network === 'regtest') {
     this._network = 'testnet';
   }
+
+  // caches
+  this._cacheTx = LRU(1000);
 }
 
 inherits(TransactionService, BaseService);
@@ -113,12 +117,25 @@ TransactionService.prototype.getTransaction = function(txid, options, callback)
     callback = options;
   }
 
+  var cacheTx = self._cacheTx.get(txid);
+  if (cacheTx) {
+    return callback(null, cacheTx);
+  }
+
   async.waterfall([
     self._getTransaction.bind(self, txid, options),
     self._getSupplementaryTransactionInfo.bind(self),
     self._getMempoolTransaction.bind(self),
     self.setTxMetaInfo.bind(self)
-  ], callback);
+  ], function(err, tx) {
+    if (err) {
+      return callback(err);
+    }
+    if (tx) {
+      self._cacheTx.set(txid, tx);
+    }
+    callback(err, tx);
+  });
 
 };