tweaks and docs on cacheKeyFn

Author: Brian Detering

README.md

@@ -90,6 +90,7 @@ All the options available to Facebook Dataloader can be passed in here. An
 additional option called **expire** is also available, and will set a ttl in seconds
 on all keys set in redis if this option is passed.
 
+By default, the "cacheKeyFn" will serialize objects and arrays using [json-stable-stringify](https://github.com/substack/json-stable-stringify) and allow all other values to pass through unchanged.
 
 ### Caching
 

index.js

@@ -92,16 +92,7 @@ module.exports = fig => {
       this.opt = _.pick(opt, customOptions) || {};
 
       this.opt.cacheKeyFn =
-        this.opt.cacheKeyFn ||
-        (k => {
-          if (_.isString(k)) {
-            return k;
-          } else if (_.isObject(k)) {
-            return stringify(k);
-          } else {
-            throw new TypeError('Key must be a string or a json object');
-          }
-        });
+        this.opt.cacheKeyFn || (k => (_.isObject(k) ? stringify(k) : k));
 
       this.keySpace = ks;
       this.loader = new DataLoader(

package.json

@@ -1,6 +1,6 @@
 {
   "name": "redis-dataloader",
-  "version": "0.4.0",
+  "version": "0.4.1",
   "description": "DataLoader Using Redis as a Cache",
   "main": "index.js",
   "scripts": {