Revert "Revert "Reapply "move ZooKeeperServer to another module"""

4 files changed, 283 insertions, 0 deletions

diff --git a/zookeeper-server/pom.xml b/zookeeper-server/pom.xml
index 54d73b8a702..3ccda41d1b9 100644
--- a/zookeeper-server/pom.xml
+++ b/zookeeper-server/pom.xml
@@ -45,6 +45,12 @@
       <groupId>org.apache.zookeeper</groupId>
       <artifactId>zookeeper</artifactId>
     </dependency>
+    <dependency>
+      <!-- Needed to have the same version as slf4j-api -->
+      <groupId>org.slf4j</groupId>
+      <artifactId>slf4j-log4j12</artifactId>
+      <version>1.7.5</version>
+    </dependency>
   </dependencies>
   <build>
     <plugins>
diff --git a/zookeeper-server/src/main/java/com/yahoo/vespa/zookeeper/ZooKeeperServer.java b/zookeeper-server/src/main/java/com/yahoo/vespa/zookeeper/ZooKeeperServer.java
new file mode 100644
index 00000000000..252dc6697b0
--- /dev/null
+++ b/zookeeper-server/src/main/java/com/yahoo/vespa/zookeeper/ZooKeeperServer.java
@@ -0,0 +1,132 @@
+// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.zookeeper;
+
+import com.google.inject.Inject;
+import com.yahoo.cloud.config.ZookeeperServerConfig;
+import com.yahoo.component.AbstractComponent;
+import com.yahoo.log.LogLevel;
+import static com.yahoo.vespa.defaults.Defaults.getDefaults;
+
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.util.List;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+/**
+ * Writes zookeeper config and starts zookeeper server.
+ *
+ * @author Ulf Lilleengen
+ */
+public class ZooKeeperServer extends AbstractComponent implements Runnable {
+
+    private static final java.util.logging.Logger log = java.util.logging.Logger.getLogger(ZooKeeperServer.class.getName());
+    private static final String ZOOKEEPER_JMX_LOG4J_DISABLE = "zookeeper.jmx.log4j.disable";
+    static final String ZOOKEEPER_JUTE_MAX_BUFFER = "jute.maxbuffer";
+    private final Thread zkServerThread;
+    private final ZookeeperServerConfig zookeeperServerConfig;
+
+    ZooKeeperServer(ZookeeperServerConfig zookeeperServerConfig, boolean startServer) {
+        this.zookeeperServerConfig = zookeeperServerConfig;
+        System.setProperty("zookeeper.jmx.log4j.disable", "true");
+        System.setProperty("zookeeper.snapshot.trust.empty", Boolean.valueOf(zookeeperServerConfig.trustEmptySnapshot()).toString());
+        System.setProperty(ZOOKEEPER_JUTE_MAX_BUFFER, Integer.valueOf(zookeeperServerConfig.juteMaxBuffer()).toString());
+
+        writeConfigToDisk(zookeeperServerConfig);
+        zkServerThread = new Thread(this, "zookeeper server");
+        if (startServer) {
+            zkServerThread.start();
+        }
+    }
+
+    @Inject
+    public ZooKeeperServer(ZookeeperServerConfig zookeeperServerConfig) {
+        this(zookeeperServerConfig, true);
+    }
+
+    private void writeConfigToDisk(ZookeeperServerConfig config) {
+       String configFilePath = getDefaults().underVespaHome(config.zooKeeperConfigFile());
+       new File(configFilePath).getParentFile().mkdirs();
+       try (FileWriter writer = new FileWriter(configFilePath)) {
+           writer.write(transformConfigToString(config));
+           writeMyIdFile(config);
+       } catch (IOException e) {
+           throw new RuntimeException("Error writing zookeeper config", e);
+       }
+   }
+
+    private String transformConfigToString(ZookeeperServerConfig config) {
+        StringBuilder sb = new StringBuilder();
+        sb.append("tickTime=").append(config.tickTime()).append("\n");
+        sb.append("initLimit=").append(config.initLimit()).append("\n");
+        sb.append("syncLimit=").append(config.syncLimit()).append("\n");
+        sb.append("maxClientCnxns=").append(config.maxClientConnections()).append("\n");
+        sb.append("snapCount=").append(config.snapshotCount()).append("\n");
+        sb.append("dataDir=").append(getDefaults().underVespaHome(config.dataDir())).append("\n");
+        sb.append("clientPort=").append(config.clientPort()).append("\n");
+        sb.append("autopurge.purgeInterval=").append(config.autopurge().purgeInterval()).append("\n");
+        sb.append("autopurge.snapRetainCount=").append(config.autopurge().snapRetainCount()).append("\n");
+        // See http://zookeeper.apache.org/doc/r3.4.13/zookeeperAdmin.html#sc_zkCommands
+        // Includes all available commands in 3.4, except 'wchc' and 'wchp'
+        // Mandatory when using ZooKeeper 3.5
+        sb.append("4lw.commands.whitelist=conf,cons,crst,dump,envi,mntr,ruok,srst,srvr,stat,wchs").append("\n");
+        ensureThisServerIsRepresented(config.myid(), config.server());
+        config.server().forEach(server -> addServerToCfg(sb, server));
+        return sb.toString();
+    }
+
+    private void writeMyIdFile(ZookeeperServerConfig config) throws IOException {
+        if (config.server().size() > 1) {
+            try (FileWriter writer = new FileWriter(getDefaults().underVespaHome(config.myidFile()))) {
+                writer.write(config.myid() + "\n");
+            }
+        }
+    }
+
+    private void ensureThisServerIsRepresented(int myid, List<ZookeeperServerConfig.Server> servers) {
+        boolean found = false;
+        for (ZookeeperServerConfig.Server server : servers) {
+            if (myid == server.id()) {
+                found = true;
+                break;
+            }
+        }
+        if (!found) {
+            throw new RuntimeException("No id in zookeeper server list that corresponds to my id(" + myid + ")");
+        }
+    }
+
+    private void addServerToCfg(StringBuilder sb, ZookeeperServerConfig.Server server) {
+        sb.append("server.").append(server.id()).append("=").append(server.hostname()).append(":").append(server.quorumPort()).append(":").append(server.electionPort()).append("\n");
+    }
+
+    private void shutdown() {
+        zkServerThread.interrupt();
+        try {
+            zkServerThread.join();
+        } catch (InterruptedException e) {
+            log.log(LogLevel.WARNING, "Error joining server thread on shutdown", e);
+        }
+    }
+
+    @Override
+    public void run() {
+        System.setProperty(ZOOKEEPER_JMX_LOG4J_DISABLE, "true");
+        String[] args = new String[]{getDefaults().underVespaHome(zookeeperServerConfig.zooKeeperConfigFile())};
+        log.log(LogLevel.DEBUG, "Starting ZooKeeper server with config file " + args[0]);
+        log.log(LogLevel.INFO, "Trying to establish ZooKeeper quorum (from " + zookeeperServerHostnames(zookeeperServerConfig) + ")");
+        org.apache.zookeeper.server.quorum.QuorumPeerMain.main(args);
+    }
+
+    @Override
+    public void deconstruct() {
+        shutdown();
+        super.deconstruct();
+    }
+
+    private static Set<String> zookeeperServerHostnames(ZookeeperServerConfig zookeeperServerConfig) {
+        return zookeeperServerConfig.server().stream().map(ZookeeperServerConfig.Server::hostname).collect(Collectors.toSet());
+    }
+
+}
diff --git a/zookeeper-server/src/main/java/com/yahoo/vespa/zookeeper/package-info.java b/zookeeper-server/src/main/java/com/yahoo/vespa/zookeeper/package-info.java
new file mode 100644
index 00000000000..470d1350f9c
--- /dev/null
+++ b/zookeeper-server/src/main/java/com/yahoo/vespa/zookeeper/package-info.java
@@ -0,0 +1,5 @@
+// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+@ExportPackage
+package com.yahoo.vespa.zookeeper;
+
+import com.yahoo.osgi.annotation.ExportPackage;
diff --git a/zookeeper-server/src/test/java/com/yahoo/vespa/zookeeper/ZooKeeperServerTest.java b/zookeeper-server/src/test/java/com/yahoo/vespa/zookeeper/ZooKeeperServerTest.java
new file mode 100644
index 00000000000..3f33892fd45
--- /dev/null
+++ b/zookeeper-server/src/test/java/com/yahoo/vespa/zookeeper/ZooKeeperServerTest.java
@@ -0,0 +1,140 @@
+// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.zookeeper;
+
+import com.yahoo.cloud.config.ZookeeperServerConfig;
+import com.yahoo.io.IOUtils;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.TemporaryFolder;
+
+import java.io.File;
+import java.io.IOException;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+import static com.yahoo.vespa.defaults.Defaults.getDefaults;
+
+/**
+ * Tests the zookeeper server.
+ */
+public class ZooKeeperServerTest {
+
+    @Rule
+    public TemporaryFolder folder = new TemporaryFolder();
+
+    @Test
+    public void config_is_written_correctly_when_one_server() throws IOException {
+        File cfgFile = folder.newFile();
+        File idFile = folder.newFile();
+        ZookeeperServerConfig.Builder builder = new ZookeeperServerConfig.Builder();
+        builder.zooKeeperConfigFile(cfgFile.getAbsolutePath());
+        builder.myidFile(idFile.getAbsolutePath());
+        builder.server(newServer(0, "foo", 123, 321));
+        builder.myid(0);
+        createServer(builder);
+        validateConfigFileSingleHost(cfgFile);
+        validateIdFile(idFile, "");
+    }
+
+    @Test
+    public void config_is_written_correctly_when_multiple_servers() throws IOException {
+        File cfgFile = folder.newFile();
+        File idFile = folder.newFile();
+        ZookeeperServerConfig.Builder builder = new ZookeeperServerConfig.Builder();
+        builder.zooKeeperConfigFile(cfgFile.getAbsolutePath());
+        builder.server(newServer(0, "foo", 123, 321));
+        builder.server(newServer(1, "bar", 234, 432));
+        builder.server(newServer(2, "baz", 345, 543));
+        builder.myidFile(idFile.getAbsolutePath());
+        builder.myid(1);
+        createServer(builder);
+        validateConfigFileMultipleHosts(cfgFile);
+        validateIdFile(idFile, "1\n");
+    }
+
+    private void createServer(ZookeeperServerConfig.Builder builder) {
+        new ZooKeeperServer(new ZookeeperServerConfig(builder), false);
+    }
+
+    @Test(expected = RuntimeException.class)
+    public void require_that_this_id_must_be_present_amongst_servers() {
+        ZookeeperServerConfig.Builder builder = new ZookeeperServerConfig.Builder();
+        builder.server(newServer(1, "bar", 234, 432));
+        builder.server(newServer(2, "baz", 345, 543));
+        builder.myid(0);
+        createServer(builder);
+    }
+
+    @Test
+    public void juteMaxBufferCanBeSet() throws IOException {
+        ZookeeperServerConfig.Builder builder = new ZookeeperServerConfig.Builder();
+        builder.myid(0);
+        File idFile = folder.newFile();
+        File cfgFile = folder.newFile();
+
+        builder.server(new ZookeeperServerConfig.Server.Builder().id(0).hostname("testhost"));
+        builder.zooKeeperConfigFile(cfgFile.getAbsolutePath());
+        builder.myidFile(idFile.getAbsolutePath());
+
+        createServer(builder);
+        assertThat(System.getProperty(ZooKeeperServer.ZOOKEEPER_JUTE_MAX_BUFFER), is("" + new ZookeeperServerConfig(builder).juteMaxBuffer()));
+
+        final int max_buffer = 1;
+        builder.juteMaxBuffer(max_buffer);
+        createServer(builder);
+        assertThat(System.getProperty(ZooKeeperServer.ZOOKEEPER_JUTE_MAX_BUFFER), is("" + max_buffer));
+    }
+
+    private ZookeeperServerConfig.Server.Builder newServer(int id, String hostName, int electionPort, int quorumPort) {
+        ZookeeperServerConfig.Server.Builder builder = new ZookeeperServerConfig.Server.Builder();
+        builder.id(id);
+        builder.hostname(hostName);
+        builder.electionPort(electionPort);
+        builder.quorumPort(quorumPort);
+        return builder;
+    }
+
+    private void validateIdFile(File idFile, String expected) throws IOException {
+        String actual = IOUtils.readFile(idFile);
+        assertThat(actual, is(expected));
+    }
+
+    private void validateConfigFileSingleHost(File cfgFile) throws IOException {
+        String expected =
+            "tickTime=2000\n" +
+            "initLimit=20\n" +
+            "syncLimit=15\n" +
+            "maxClientCnxns=0\n" +
+            "snapCount=50000\n" +
+            "dataDir=" + getDefaults().underVespaHome("var/zookeeper") + "\n" +
+            "clientPort=2181\n" +
+            "autopurge.purgeInterval=1\n" +
+            "autopurge.snapRetainCount=15\n" +
+            "4lw.commands.whitelist=conf,cons,crst,dump,envi,mntr,ruok,srst,srvr,stat,wchs\n" +
+            "server.0=foo:321:123\n";
+        validateConfigFile(cfgFile, expected);
+    }
+
+    private void validateConfigFileMultipleHosts(File cfgFile) throws IOException {
+        String expected =
+                "tickTime=2000\n" +
+                        "initLimit=20\n" +
+                        "syncLimit=15\n" +
+                        "maxClientCnxns=0\n" +
+                        "snapCount=50000\n" +
+                        "dataDir=" + getDefaults().underVespaHome("var/zookeeper") + "\n" +
+                        "clientPort=2181\n" +
+                        "autopurge.purgeInterval=1\n" +
+                        "autopurge.snapRetainCount=15\n" +
+                        "4lw.commands.whitelist=conf,cons,crst,dump,envi,mntr,ruok,srst,srvr,stat,wchs\n" +
+                        "server.0=foo:321:123\n" +
+                        "server.1=bar:432:234\n" +
+                        "server.2=baz:543:345\n";
+        validateConfigFile(cfgFile, expected);
+    }
+
+    private void validateConfigFile(File cfgFile, String expected) throws IOException {
+        String actual = IOUtils.readFile(cfgFile);
+        assertThat(actual, is(expected));
+    }
+}