chore: update readme

README.md

@@ -1,33 +1,47 @@
 # promise-cache-memorize #
 
 [![Build Status](https://travis-ci.org/sdvcrx/promise-cache.svg?branch=master)](https://travis-ci.org/sdvcrx/promise-cache)
-
 [![npm package](https://img.shields.io/npm/v/promise-cache-memorize.svg)](https://www.npmjs.com/package/promise-cache-memorize)
 
 Memoize promise-returning functions.
 
 ## Usage ##
 
-#### promiseMemorize.remember(key, fn, maxAge) -> memorizedFn ####
+```javascript
+const Cache = require('promise-cache-memorize')('redis')
+
+const requestWithCache = Cache.remember('request', request)
+```
+
+### cacheFactory(type, options) -> Cache ###
+
+Factory function that configuring and returning actual `Cache` object.
+
+* **type** - cache backend. Current support `simple` , `lru` or `redis`
+
+* **options** - cache backend configuration.
+
+  * **timeout** - (default: 3600) cache expire timeout, 1 hour by default
+
+
+  * if it is [redis](https://github.com/luin/ioredis) backend, see [ioredis document](https://github.com/luin/ioredis/blob/master/API.md#new-redisport-host-options)
+  * if it is [lru](https://github.com/isaacs/node-lru-cache) backend, see [lru document](https://github.com/isaacs/node-lru-cache#options)
+
+#### Cache.remember(key, fn, maxAge) -> memorizedFn ####
 
 Memorize promise-returning functions `fn` with `key`.
 
 * **fn** - function that returning promise.
 * **key** - string using as cache key.
-* **maxAge** - (default: 0) cache expired after `maxAge` seconds.
-
-```javascript
-const promiseMemorize = require('promise-cache-memorize')
-const requestWithCache = promiseMemorize.remember('request', request)
-```
+* **maxAge** - (default: options.timeout) cache expired after `maxAge` seconds.
 
 ## Example ##
 
 ```javascript
 const request = require('request-promise')
-const promiseMemorize = require('promise-cache-memorize')
+const Cache = require('promise-cache-memorize')('redis')
 
-const requestWithCache = promiseMemorize.remember('request', request)
+const requestWithCache = Cache.remember('request', request)
 
 function sendRequest () {
   return requestWithCache('http://httpbin.org/get')
@@ -45,9 +59,9 @@ sendRequest().then((res) => {
 
 ## TODO ##
 
-- [ ] Provide options for cache type
-- [ ] Multiple cache backend support
+- [x] Provide options for cache type
+- [x] Multiple cache backend support
 
 ## License ##
 
-MIT
+MIT