RedisShardingClient: initial skeleton, updated readme

Author: Ben Buckman

README.md

@@ -3,21 +3,24 @@ redis - a node.js redis client
 
 This is a fork of [node_redis](https://github.com/mranney/node_redis), the complete Redis client for node.js.
 
-The purpose of this fork is to implement support for [Redis Sentinel](http://redis.io/topics/sentinel).
+The purpose of this fork is to:
 
+1. Implement support for [Redis Sentinel](http://redis.io/topics/sentinel) via a `RedisSentinalClient`.
+  - See related thread: https://github.com/mranney/node_redis/issues/302
+2. Implement support for Redis sharding via a `RedisShardingClient`.
+  - See related thread: https://github.com/mranney/node_redis/issues/116
 
-See related thread: https://github.com/mranney/node_redis/issues/302
 
+# `RedisSentinelClient`
 
-# Concept
+### Concepts
 
-- `RedisSentinelClient`
-    - connects to a single sentinel, which is watching a single master/slave(s) cluster
-    - maintains an activeMasterClient in the background, automatically updates on failover (using psub)
-    - behaves exactly like a single RedisClient
-    - passes thru all client commands, behaves transparently like a `RedisClient`
+- connects to a single sentinel, which is watching a single master/slave(s) cluster
+- maintains an activeMasterClient in the background, automatically updates on failover (using psub)
+- behaves exactly like a single RedisClient
+- passes thru all client commands, behaves transparently like a `RedisClient`
 
-# Usage
+### Usage
 
 ```
 var redis = require('redis');
@@ -26,20 +29,21 @@ var sentinelClient = redis.createClient(PORT, HOST, { sentinel: true });
 
 Now use `sentinelClient` as a regular client: `set`, `get`, `hmset`, etc.
 
-## Options
+### RedisSentinelClient Options
+
 - `masterName`: Which master the sentinel is listening to. Defaults to 'mymaster'. (If a sentinel is listening to multiple masters, create multiple `RedisSentinelClients`.)
 - `logger`: pass in [winston](https://github.com/flatiron/winston) or another custom logger, otherwises uses console. (Expects a `log` method.)
 - `debug`: verbose output (to `logger` about internal ops)
 
 
-## RedisSentinelClient Methods
+### RedisSentinelClient Methods
 
 - `getMaster()`: returns a reference to the sentinel client's `activeMasterClient` (also available directly)
 - `reconnect()`: used on instantiation and on psub events, this checks if the master has changed and connects to the new master.
 - `send_command()` (and any other `RedisClient` command): command is passed to the master client.
 
 
-## RedisSentinelClient Events
+### RedisSentinelClient Events
 
 - `sentinel message` (`msg`): passed up from the sentinel's channel listener. Note, messages can be about other masters, does not differentiate.
 - `failover-start`: corresponds to sentinel's `+failover-triggered` message.
@@ -50,7 +54,7 @@ Now use `sentinelClient` as a regular client: `set`, `get`, `hmset`, etc.
 - `error` (`error`): An error occured. (Currently does not differentiate errors in different components.) Will fire errors during a failover, before new master is connected.
 
 
-# Limitations
+### RedisSentinelClient Limitations
 
 - Unlike `RedisClient`, `RedisSentinelClient` is not / does not need to be a stream
 - Sentinel docs don't specify a default host+port, so option-less implementations of `createClient()` won't be compatible
@@ -59,8 +63,12 @@ Now use `sentinelClient` as a regular client: `set`, `get`, `hmset`, etc.
 - With non-atomic operations like pub/sub, your code needs to listen to `reconnect` events and reload its client.
 
 
-# Possible roadmap
+### Possible roadmap
 
 - Multiple master/slave(s) clusters per sentinel
   - But thinking not: Just create multiple sentinel clients, one per cluster.
 
+
+# `RedisShardingClient`
+
+To be continued...

index.js

@@ -1113,6 +1113,12 @@ var Sentinel = require('./lib/sentinel');
 exports.RedisSentinelClient = Sentinel.RedisSentinelClient;
 
 
+// sharding client. instantiate separately.
+var Sharding = require('./lib/sharding');
+exports.RedisShardingClient = Sharding.RedisShardingClient;
+
+
+
 exports.createClient = function (port_arg, host_arg, options) {
     var redis_client;
     var net_client;

lib/sharding.js

@@ -0,0 +1,22 @@
+/**
+[Ben Buckman @ DocuSign]
+
+Adds Redis sharding support, via RedisShardingClient.
+Modeled on the RedisSentinelClient (also added in our fork).
+
+(see readme for notes)
+*/
+
+var RedisSingleClient = require('../index'),
+    events = require('events'),
+    util = require('util'),
+    reply_to_object = require('./utils').reply_to_object,
+    commands = RedisSingleClient.commands,
+    to_array = require('./to_array');
+
+
+function RedisShardingClient(options) {
+}
+
+
+exports.RedisShardingClient = RedisShardingClient;