Added pagination.

lib/services/wallet-api/index.js

@@ -17,6 +17,7 @@ var validators = require('./validators');
 var utils = require('./utils');
 var _ = require('lodash');
 var bodyParser = require('body-parser');
+var LRU = require('lru-cache');
 
 var WalletService = function(options) {
   BaseService.call(this, options);
@@ -25,6 +26,13 @@ var WalletService = function(options) {
     valueEncoding: 'json'
   };
   this._db = levelup(options.dbPath, this._dbOptions);
+  this._cache = LRU({
+    max: 500 * 1024 * 1024,
+    length: function(n, key) {
+      return Buffer.byteLength(n, 'utf8');
+    },
+    maxAge: 30 * 60 * 1000
+  });
 };
 
 inherits(WalletService, BaseService);
@@ -241,31 +249,54 @@ WalletService.prototype._chunkAdresses = function(addresses) {
 
 WalletService.prototype._getTransactions = function(walletId, options, callback) {
   var self = this;
-  self._getAddresses(walletId, function(err, addresses) {
-    if(err) {
-      return callback(err);
-    }
-    if (!addresses) {
-      return callback(new Error('wallet not found'));
-    }
-    var addressGroups = self._chunkAdresses(addresses);
-    var transactions = [];
-    async.eachSeries(addressGroups, function(addresses, next) {
-      self.node.services.bitcoind.getAddressHistory(addresses, options, function(err, history) {
+  var transactions = [];
+  var opts = {
+    start: options.start,
+    end: options.end
+  };
+  var key = walletId + opts.start + opts.end;
+  if (!self._cache.peek(key)) {
+    self._getAddresses(walletId, function(err, addresses) {
+      if(err) {
+        return callback(err);
+      }
+      if (!addresses) {
+        return callback(new Error('wallet not found'));
+      }
+      var addressGroups = self._chunkAdresses(addresses);
+      async.eachSeries(addressGroups, function(addresses, next) {
+        self.node.services.bitcoind.getAddressHistory(addresses, opts, function(err, history) {
+          if(err) {
+            return next(err);
+          }
+          var groupTransactions = history.items.map(function(item) {
+            return item.tx;
+          });
+          transactions = _.union(transactions, groupTransactions);
+          next();
+        });
+      }, function(err) {
         if(err) {
           return callback(err);
         }
-        var groupTransactions = history.items.map(function(item) {
-          return item.tx;
-        });
-        transactions = _.union(transactions, groupTransactions);
-        next();
+        self._cache.set(key, JSON.stringify(transactions));
+        finish();
       });
-
-    }, function(err) {
-        callback(null, transactions, transactions.length);
     });
-  });
+  } else {
+    try {
+      transactions = JSON.parse(self._cache.get(key));
+      finish();
+    } catch(e) {
+      self._cache.del(key);
+      return callback(e);
+    }
+  }
+  function finish() {
+    var from = options.from || 0;
+    var to = options.to || transactions.length;
+    callback(null, transactions.slice(from, to), transactions.length);
+  }
 };
 
 WalletService.prototype._getAddresses = function(walletId, callback) {

package.json

@@ -56,7 +56,7 @@
     "levelup": "^1.3.3",
     "liftoff": "^2.2.0",
     "lodash": "^4.17.4",
-    "lru-cache": "^4.0.1",
+    "lru-cache": "^4.0.2",
     "mkdirp": "0.5.0",
     "multer": "^1.2.1",
     "path-is-absolute": "^1.0.0",