Use string key if getRangeBuffer is available (#4)

Author: heri16

lib/redis-rstream.js

@@ -14,7 +14,7 @@ function RedisRStream(client, key, options) {
   if (!(this instanceof RedisRStream)) return new RedisRStream(client, key, options);
   Readable.call(this, options);
   this._redisClient = client;
-  this._redisKey = new Buffer(key); // using Buffer key so redis returns buffers
+  this._redisKey = !!client.getrangeBuffer ? key : new Buffer(key); // using Buffer key so redis returns buffers
   this._redisChunkSize = (options && options.chunkSize) ? options.chunkSize : 64 * 1024;  // default 64KB
   this._redisMaxPendingReads = (options && options.maxPendingReads) ? options.maxPendingReads : 2;
   this._redisOffset = (options && options.startOffset) ? options.startOffset : 0;
@@ -23,7 +23,6 @@ function RedisRStream(client, key, options) {
   this._redisLength = 0;
   this._redisEnded = false;
   this._redisPendingReads = 0;
-  this._redisHasSuffixBufferAPI = !!client.getrangeBuffer
 }
 
 util.inherits(RedisRStream, Readable);
@@ -70,7 +69,7 @@ RedisRStream.prototype._read = function _read(size) {
       return;
     }
   };
-  if (this._redisHasSuffixBufferAPI) {
+  if (self._redisClient.getrangeBuffer) {
     self._redisClient.getrangeBuffer(self._redisKey, startOffset, endOffset, getrangeCallback)
   } else {
     self._redisClient.getrange(self._redisKey, startOffset, endOffset, getrangeCallback)