From fdb8285759bec264cca42337df240452568620fa Mon Sep 17 00:00:00 2001
From: Matias Alejo Garcia <ematiu@gmail.com>
Date: Sun, 5 Apr 2015 15:42:56 -0300
Subject: [PATCH] add multilevel support

---
 config.js           | 10 ++++----
 lib/storage.js      | 57 ++++++++++++++++++++++++++++-----------------
 multilevel/start.js | 14 +++++++++++
 package.json        |  2 ++
 4 files changed, 57 insertions(+), 26 deletions(-)
 create mode 100755 multilevel/start.js

diff --git a/config.js b/config.js
index d017e77..c13db93 100644
--- a/config.js
+++ b/config.js
@@ -14,10 +14,12 @@ var config = {
   WalletService: {
     storageOpts: {
       dbPath: './db',
-      /*
-      dbHost: 'http://db.host.org',
-      dbPort: '8188',
-       */
+      /*  To use multilevel, uncomment this:
+      multiLevel: {
+        host: 'localhost',
+        port: 3002,
+      },
+     */
     },
   },
 };
diff --git a/lib/storage.js b/lib/storage.js
index 37db926..32583c8 100644
--- a/lib/storage.js
+++ b/lib/storage.js
@@ -2,6 +2,8 @@
 
 var _ = require('lodash');
 var levelup = require('levelup');
+var multilevel = require('multilevel');
+var net = require('net');
 var async = require('async');
 var $ = require('preconditions').singleton();
 var log = require('npmlog');
@@ -16,9 +18,20 @@ var Notification = require('./model/notification');
 
 var Storage = function(opts) {
   opts = opts || {};
-  this.db = opts.db || levelup(opts.dbPath || './db/bws.db', {
-    valueEncoding: 'json'
-  });
+  this.db = opts.db;
+
+  if (!this.db) {
+    if (opts.multiLevel) {
+      this.db = multilevel.client();
+      var con = net.connect(opts.multiLevel);
+      con.pipe(this.db.createRpcStream()).pipe(con);
+      console.log('Connected to multilevel server at:', opts.multiLevel);
+    } else {
+      this.db = levelup(opts.dbPath || './db/bws.db', {
+        valueEncoding: 'json'
+      });
+    }
+  }
 };
 
 var zeroPad = function(x, length) {
@@ -134,9 +147,9 @@ Storage.prototype.fetchPendingTxs = function(walletId, cb) {
   var txs = [];
   var key = KEY.PENDING_TXP(walletId);
   this.db.createReadStream({
-    gte: key,
-    lt: key + '~'
-  })
+      gte: key,
+      lt: key + '~'
+    })
     .on('data', function(data) {
       txs.push(TxProposal.fromObj(data.value));
     })
@@ -170,11 +183,11 @@ Storage.prototype.fetchTxs = function(walletId, opts, cb) {
   var endkey = KEY.TXP(walletId, opts.maxTs);
 
   this.db.createReadStream({
-    gt: key,
-    lt: endkey + '~',
-    reverse: true,
-    limit: opts.limit,
-  })
+      gt: key,
+      lt: endkey + '~',
+      reverse: true,
+      limit: opts.limit,
+    })
     .on('data', function(data) {
       txs.push(TxProposal.fromObj(data.value));
     })
@@ -207,11 +220,11 @@ Storage.prototype.fetchNotifications = function(walletId, opts, cb) {
   var endkey = KEY.NOTIFICATION(walletId, opts.maxTs);
 
   this.db.createReadStream({
-    gt: key,
-    lt: endkey + '~',
-    reverse: opts.reverse,
-    limit: opts.limit,
-  })
+      gt: key,
+      lt: endkey + '~',
+      reverse: opts.reverse,
+      limit: opts.limit,
+    })
     .on('data', function(data) {
       txs.push(Notification.fromObj(data.value));
     })
@@ -271,9 +284,9 @@ Storage.prototype._delByKey = function(key, cb) {
   var self = this;
   var keys = [];
   this.db.createKeyStream({
-    gte: key,
-    lt: key + '~',
-  })
+      gte: key,
+      lt: key + '~',
+    })
     .on('data', function(key) {
       keys.push(key);
     })
@@ -328,9 +341,9 @@ Storage.prototype.fetchAddresses = function(walletId, cb) {
   var addresses = [];
   var key = KEY.ADDRESS(walletId);
   this.db.createReadStream({
-    gte: key,
-    lt: key + '~'
-  })
+      gte: key,
+      lt: key + '~'
+    })
     .on('data', function(data) {
       addresses.push(Address.fromObj(data.value));
     })
diff --git a/multilevel/start.js b/multilevel/start.js
new file mode 100755
index 0000000..591ccd2
--- /dev/null
+++ b/multilevel/start.js
@@ -0,0 +1,14 @@
+var multilevel = require('multilevel');
+var net = require('net');
+var level = require('levelup');
+
+var db = level('./db', {
+  valueEncoding: 'json'
+});
+var PORT = 3002;
+
+
+console.log('Server started at port ' + PORT + '...');
+net.createServer(function(con) {
+  con.pipe(multilevel.server(db)).pipe(con);
+}).listen(PORT);
diff --git a/package.json b/package.json
index 0f45b2d..1729ada 100644
--- a/package.json
+++ b/package.json
@@ -26,11 +26,13 @@
     "coveralls": "^2.11.2",
     "express": "^4.10.0",
     "inherits": "^2.0.1",
+    "level": "^0.18.0",
     "leveldown": "^0.10.0",
     "levelup": "^0.19.0",
     "lodash": "^3.3.1",
     "mocha-lcov-reporter": "0.0.1",
     "morgan": "*",
+    "multilevel": "^6.1.0",
     "npmlog": "^0.1.1",
     "preconditions": "^1.0.7",
     "read": "^1.0.5",