initial load.

Author: Ryan

src/test/com/mongodb/SecondaryReadTest.java

@@ -0,0 +1,176 @@
+/**
+ * Copyright (C) 2008 10gen Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.mongodb;
+
+// Mongo
+import com.mongodb.*;
+import org.bson.types.*;
+import com.mongodb.util.*;
+
+import org.testng.annotations.Test;
+
+
+// Java
+import java.util.*;
+import java.util.concurrent.*;
+
+public class SecondaryReadTest extends TestCase {
+
+
+    private static final int INSERT_COUNT = 1000;
+
+    private static final int ITERATION_COUNT = 100;
+
+    private static final int TOTAL_COUNT = INSERT_COUNT * ITERATION_COUNT;
+
+    private static final double MAX_DEVIATION_PERCENT = 1.0;
+
+    @Test(groups = {"basic"})
+    @SuppressWarnings({"unchecked"})
+    public void testSecondaryReads() throws Exception {
+
+        final Mongo mongo = new Mongo(new MongoURI("mongodb://127.0.0.1:27017,127.0.0.1:27018"));
+
+        // Check to see if this is a replica set... if not, get out of here.
+        final CommandResult result = mongo.getDB("admin").command(new BasicDBObject("replSetGetStatus", 1));
+
+        final String errorMsg = result.getErrorMessage();
+
+        if (errorMsg != null && errorMsg.indexOf("--replSet") != -1) {
+            System.err.println("---- SecondaryReadTest: This is not a replica set - not testing secondary reads");
+            return;
+        }
+
+        String primaryHostnameAndPort = null;
+
+        // Extract the repl set members.
+        final List<TestHost> testHosts = new ArrayList<TestHost>();
+        for (final BasicDBObject member : (List<BasicDBObject>)result.get("members")) {
+            String hostnameAndPort = member.getString("name");
+            if (hostnameAndPort.indexOf(":") == -1) hostnameAndPort = hostnameAndPort + ":27017";
+
+            final String stateStr = member.getString("stateStr");
+
+            if (stateStr.equals("PRIMARY")) primaryHostnameAndPort = hostnameAndPort;
+
+            testHosts.add(new TestHost(hostnameAndPort, stateStr));
+        }
+
+        if (primaryHostnameAndPort == null) throw new IllegalStateException("No primary defined");
+
+        mongo.getDB("com_mongodb_unittest_SecondaryReadTest").dropDatabase();
+        final DB db = mongo.getDB("com_mongodb_unittest_SecondaryReadTest");
+        final DBCollection col = db.getCollection("testBalance");
+
+        final ArrayList<ObjectId> insertedIds = new ArrayList<ObjectId>();
+
+        // Insert some test data.
+        for (int idx=0; idx < INSERT_COUNT; idx++) {
+            final ObjectId id = ObjectId.get();
+            WriteResult writeResult = col.insert(new BasicDBObject("_id", id), WriteConcern.REPLICAS_SAFE);
+            writeResult.getLastError().throwOnError();
+            insertedIds.add(id);
+        }
+
+        // Make sure everything is inserted.
+        while (true) {
+            final long count = col.count();
+            if (count == INSERT_COUNT) break;
+            Thread.sleep(1000);
+        }
+
+        // Get the opcounter/query data for the hosts.
+        loadQueryCount(testHosts, true);
+
+        int secondaryCount = 0;
+
+        for (final TestHost testHost : testHosts) if (testHost.stateStr.equals("SECONDARY")) secondaryCount++;
+
+        // Perform some reads on the secondaries
+        col.setReadPreference(ReadPreference.SECONDARY);
+
+        for (int idx=0; idx < ITERATION_COUNT; idx++) {
+            for (ObjectId id : insertedIds) {
+                final BasicDBObject doc = (BasicDBObject)col.findOne(new BasicDBObject("_id", id));
+                if (doc == null) throw new IllegalStateException("Doc not found");
+                if (!doc.getObjectId("_id").equals(id)) throw new IllegalStateException("Ids are off");
+            }
+        }
+
+        loadQueryCount(testHosts, false);
+
+        /*
+        for (final TestHost testHost : testHosts) {
+            System.out.println("--- host: " + testHost.hostnameAndPort + " - queries: " + testHost.queriesBefore + " - after: " + testHost.queriesAfter);
+        }
+        */
+
+        // Verify the counts.
+        final int expectedPerSecondary = TOTAL_COUNT / secondaryCount;
+
+        for (final TestHost testHost : testHosts) {
+
+            if (!testHost.stateStr.equals("SECONDARY")) continue;
+
+            final long queriesExecuted = testHost.getQueriesExecuted();
+
+            if (expectedPerSecondary == queriesExecuted) continue;
+
+            if (queriesExecuted > expectedPerSecondary) {
+                final double deviation = (double)100 - (((double)expectedPerSecondary / (double)queriesExecuted) * (double)100);
+                //System.out.println("------ deviation: " + deviation);
+                assertEquals(true, (deviation <= MAX_DEVIATION_PERCENT));
+            } else {
+                final double deviation = (double)100 - (((double)queriesExecuted / (double)expectedPerSecondary) * (double)100);
+                //System.out.println("------ deviation: " + deviation);
+                assertEquals(true, (deviation <= MAX_DEVIATION_PERCENT));
+            }
+        }
+   }
+
+    private static void loadQueryCount(final List<TestHost> pHosts, final boolean pBefore) throws Exception {
+        for (final TestHost testHost : pHosts) {
+            final Mongo mongoHost = new Mongo(new MongoURI("mongodb://"+testHost.hostnameAndPort));
+            try {
+                final CommandResult serverStatusResult
+                = mongoHost.getDB("com_mongodb_unittest_SecondaryReadTest").command(new BasicDBObject("serverStatus", 1));
+
+                final BasicDBObject opcounters = (BasicDBObject)serverStatusResult.get("opcounters");
+
+                if (pBefore) testHost.queriesBefore = opcounters.getLong("query");
+                else testHost.queriesAfter = opcounters.getLong("query");
+
+            } finally { mongoHost.close(); }
+        }
+    }
+
+    private static class TestHost {
+        private final String hostnameAndPort;
+        private final String stateStr;
+
+        private long queriesBefore;
+        private long queriesAfter;
+
+        public long getQueriesExecuted() { return queriesAfter - queriesBefore; }
+
+        private TestHost(final String pHostnameAndPort, final String pStateStr) {
+            hostnameAndPort = pHostnameAndPort;
+            stateStr = pStateStr;
+        }
+    }
+}
+