Use more efficient lookup by index

Author: stephen-palmer

lib/cache/cache_ram.js

@@ -97,7 +97,11 @@ class CacheRAM extends CacheBase {
 
     _reserveBlock(key, size) {
         // Free any existing block for this key
-        this._index.findAndUpdate({'fileId' : key}, doc => doc['fileId'] = undefined);
+        let doc = this._index.by('fileId', key);
+        if(doc) {
+            doc.fileId = undefined;
+            this._index.update(doc);
+        }
 
         // Find the best free block to use
         let freeBlock;
@@ -187,7 +191,10 @@ class CacheRAM extends CacheBase {
             helpers.log(consts.LOG_INFO, `Writing ${pagePath}`);
 
             await fs.writeFile(pagePath, this._pages[page.index]);
-            this._pageMeta.findAndUpdate({'index': page.index}, doc => doc.dirty = false);
+
+            let doc = this._pageMeta.by('index', page.index);
+            doc.dirty = false;
+            this._pageMeta.update(doc);
         });
 
         return Promise.all(promises);