1 files changed, 77 insertions, 0 deletions
diff --git a/container-search/src/main/java/com/yahoo/prelude/searcher/CachingSearcher.java b/container-search/src/main/java/com/yahoo/prelude/searcher/CachingSearcher.java
new file mode 100644
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+++ b/container-search/src/main/java/com/yahoo/prelude/searcher/CachingSearcher.java
@@ -0,0 +1,77 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.prelude.searcher;
+
+import com.yahoo.component.chain.dependencies.After;
+import com.yahoo.component.chain.dependencies.Before;
+import com.yahoo.container.QrSearchersConfig;
+import com.yahoo.search.Query;
+import com.yahoo.search.Result;
+import com.yahoo.prelude.cache.Cache;
+import com.yahoo.prelude.cache.QueryCacheKey;
+import com.yahoo.search.Searcher;
+import com.yahoo.processing.request.CompoundName;
+import com.yahoo.search.searchchain.Execution;
+import com.yahoo.statistics.Statistics;
+import com.yahoo.statistics.Value;
+
+/**
+ * A generic caching searcher which caches all passing results.
+ *
+ * @author vegardh
+ */
+@After("rawQuery")
+@Before("transformedQuery")
+public class CachingSearcher extends Searcher {
+
+    private static final CompoundName nocachewrite=new CompoundName("nocachewrite");
+
+    private Cache<QueryCacheKey, Result> cache;
+    private Value cacheHitRatio = null;
+
+    public CachingSearcher(QrSearchersConfig config, Statistics manager) {
+        long maxSizeBytes = config.com().yahoo().prelude().searcher().CachingSearcher().cachesizemegabytes()*1024*1024;
+        long timeToLiveMillis = config.com().yahoo().prelude().searcher().CachingSearcher().timetoliveseconds()*1000;
+        long maxEntrySizeBytes = config.com().yahoo().prelude().searcher().CachingSearcher().maxentrysizebytes();
+        cache=new Cache<>(maxSizeBytes, timeToLiveMillis, maxEntrySizeBytes, manager);
+        initRatio(manager);
+    }
+
+    private void initRatio(Statistics manager) {
+        cacheHitRatio = new Value("querycache_hit_ratio", manager,
+                new Value.Parameters().setNameExtension(false).setLogRaw(false).setLogMean(true));
+    }
+
+    private synchronized void cacheHit() {
+        cacheHitRatio.put(1.0d);
+    }
+
+    private synchronized void cacheMiss() {
+        cacheHitRatio.put(0.0d);
+    }
+
+    private boolean noCacheWrite(Query query) {
+        return query.properties().getBoolean(nocachewrite);
+    }
+
+    public Result search(com.yahoo.search.Query query, Execution execution) {
+        if (query.getNoCache()) {
+            return execution.search(query);
+        }
+        QueryCacheKey queryKey = new QueryCacheKey(query);
+        Result cachedResult=cache.get(queryKey);
+        if (cachedResult!=null) {
+            cacheHit();
+            return cachedResult;
+        }
+        cacheMiss();
+        Query originalQuery = query.clone(); // Need a copy, as cache hash key later on, maybe.
+        Result result = execution.search(query);
+        execution.fill(result);
+        if (!noCacheWrite(query)) {
+            queryKey.setQuery(originalQuery); // Because the query member has changed state
+            cache.put(queryKey,result);
+        }
+        return result;
+    }
+
+}