Adding Redis store example

Makefile

@@ -20,6 +20,7 @@ test-cov: cover check-coverage
 lint:
 	./node_modules/.bin/jshint ./lib --config $(BASE)/.jshintrc && \
 	./node_modules/.bin/jshint ./test --config $(BASE)/.jshintrc
+	./node_modules/.bin/jshint ./examples --config $(BASE)/.jshintrc
 
 
 .PHONY: test

README.md

@@ -44,6 +44,9 @@ node-cache-manager handles easily and transparently.
 
 ## Usage Examples
 
+See examples below and in the examples directory.  See ``examples/redis_example`` for an example of how to implement a
+Redis cache store with connection pooling.
+
 ### Single Store
 
 ```javascript

examples/redis_example/example.js

@@ -0,0 +1,47 @@
+// Setup:
+// npm install redis
+// npm install sol-redis-pool
+
+var cache_manager = require('../../');
+var redis_store = require('./redis_store');
+var redis_cache = cache_manager.caching({store: redis_store, db: 0, ttl: 100/*seconds*/});
+
+redis_cache.set('foo', 'bar', function (err) {
+    if (err) { throw err; }
+
+    redis_cache.get('foo', function (err, result) {
+        console.log(result);
+        // >> 'bar'
+        redis_cache.del('foo', function (err) { console.log(err); });
+    });
+});
+
+function get_user(id, cb) {
+    setTimeout(function () {
+        console.log("Returning user from slow database.");
+        cb(null, {id: id, name: 'Bob'});
+    }, 100);
+}
+
+var user_id = 123;
+var key = 'user_' + user_id;
+
+redis_cache.wrap(key, function (cb) {
+    get_user(user_id, cb);
+}, function (err, user) {
+    console.log(user);
+
+    // Second time fetches user from redis_cache 
+    redis_cache.wrap(key, function (cb) {
+        get_user(user_id, cb);
+    }, function (err, user) {
+        console.log(user);
+    });
+});
+
+// Outputs:
+// Returning user from slow database.
+// { id: 123, name: 'Bob' }
+// { id: 123, name: 'Bob' }
+
+process.exit();

examples/redis_example/redis_client.js → examples/redis_example/redis_store.js

@@ -3,9 +3,6 @@
  * cache store with connection pooling.
  */
 
-// npm install redis
-// npm install sol-redis-pool
-
 var RedisPool = require('sol-redis-pool');
 
 function redis_store(args) {
@@ -29,7 +26,7 @@ function redis_store(args) {
                 return cb(err);
             }
 
-            if (args.db) {
+            if (args.db || args.db === 0) {
                 conn.select(args.db);
             }
 
@@ -87,5 +84,3 @@ var methods = {
 };
 
 module.exports = methods;
-
-process.exit();