added cached execution statistics (#54)

* added cached execution statistics

* Update label.js

* Update redisGraphAPITest.js

* Update redisGraphAPITest.js

Co-authored-by: Guy Korland <gkorland@gmail.com>

Author: DvirDukhan

src/label.js

@@ -11,6 +11,7 @@ var Label = Object.freeze({
 	RELATIONSHIPS_CREATED: "Relationships created",
 	INDICES_CREATED: "Indices created",
 	INDICES_DELETED: "Indices deleted",
+	CACHED_EXECUTION: "Cached execution",
 	QUERY_INTERNAL_EXECUTION_TIME: "Query internal execution time"
 });
 

src/statistics.js

@@ -108,7 +108,14 @@ class Statistics {
      */
 	indicesDeleted() {
 		return this.getIntValue(Label.INDICES_DELETED);
-	}
+    }
+
+    /**
+     * @returns {boolean} The execution plan was cached on RedisGraph.
+     */
+    cachedExecution() {
+        return  this.getIntValue(Label.CACHED_EXECUTION) == 1;
+    }
 
     /**
      * @returns {float} The query execution time in ms.

test/redisGraphAPITest.js

@@ -508,5 +508,33 @@ describe("RedisGraphAPI Test", () => {
 		record = resultSet.next();
 		assert.equal(record.size(), 1);
 		assert.equal(record.get(0), null);
-	});
+    });
+    
+    it("testCachedExecution", async () => {
+        await api.query("CREATE (:N {val:1}), (:N {val:2})");
+	    
+        // First time should not be loaded from execution cache
+        let resultSet = await api.query(
+	        "MATCH (n:N {val:$val}) RETURN n.val ", {'val':1}
+        );
+        assert.equal(resultSet.size(), 1)
+        assert.equal(false, resultSet.getStatistics().cachedExecution())
+
+        let record = resultSet.next();
+        assert.equal(record.size(), 1);
+        assert.equal(record.get(0), 1);
+        
+	// Run in loop many times to make sure the query will be loaded
+	// from cache at least once
+        for (var i = 0; i < 64; i++) {
+            resultSet = await api.query(
+                "MATCH (n:N {val:$val}) RETURN n.val ", {'val':1}
+            );
+        }	
+        assert.equal(resultSet.size(), 1)
+        record = resultSet.next();
+        assert.equal(record.size(), 1);
+        assert.equal(record.get(0), 1);
+        assert.equal(true, resultSet.getStatistics().cachedExecution())
+    });
 });