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nkalmar pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/zookeeper.git
The following commit(s) were added to refs/heads/master by this push:
new 3f4d0cd ZOOKEEPER-3091: Prometheus.io Metrics Provider
3f4d0cd is described below
commit 3f4d0cda0f9688baa7ad0718e46c4ba95653dbfa
Author: Enrico Olivelli <[email protected]>
AuthorDate: Wed Jun 12 10:25:14 2019 +0200
ZOOKEEPER-3091: Prometheus.io Metrics Provider
Implement a MetricsProvider that exports data to Prometheus.io.
- introduce a new Maven module zookeeper-metrics-providers
- introduce an implementation of the MetricProvider that uses the Java
library provided by Prometheus.io
- add the Provider to the binary tar ball
- add LICENSE files for Prometheus.io jars (it is ASL 2.0)
- add docs about configuration parameters
- change zoo_sample.cfg with the available configuration options (commented
out by default)
Author: Enrico Olivelli <[email protected]>
Reviewers: Norbert Kalmar <[email protected]>
Closes #977 from eolivelli/fix/ZOOKEEPER-3091-prometheus
---
conf/zoo_sample.cfg | 8 +
pom.xml | 1 +
zookeeper-assembly/pom.xml | 5 +
.../src/main/resources/markdown/zookeeperAdmin.md | 23 ++
zookeeper-metrics-providers/pom.xml | 40 ++
.../zookeeper-prometheus-metrics/pom.xml | 86 +++++
.../prometheus/PrometheusMetricsProvider.java | 412 +++++++++++++++++++++
.../metrics/prometheus/ExportJvmInfoTest.java | 60 +++
.../prometheus/PrometheusMetricsProviderTest.java | 295 +++++++++++++++
.../src/test/resources/log4j.properties | 65 ++++
.../resources/lib/simpleclient-0.6.0.LICENSE.txt | 202 ++++++++++
.../lib/simpleclient_common-0.6.0_LICENSE.txt | 202 ++++++++++
.../lib/simpleclient_hotspot-0.6.0_LICENSE.txt | 202 ++++++++++
.../lib/simpleclient_servlet-0.6.0_LICENSE.txt | 202 ++++++++++
14 files changed, 1803 insertions(+)
diff --git a/conf/zoo_sample.cfg b/conf/zoo_sample.cfg
index a5a2c0b..24a97d7 100644
--- a/conf/zoo_sample.cfg
+++ b/conf/zoo_sample.cfg
@@ -26,3 +26,11 @@ clientPort=2181
# Purge task interval in hours
# Set to "0" to disable auto purge feature
#autopurge.purgeInterval=1
+
+## Metrics Providers
+#
+# https://prometheus.io Metrics Exporter
+#metricsProvider.className=org.apache.zookeeper.metrics.prometheus.PrometheusMetricsProvider
+#metricsProvider.httpPort=7000
+#metricsProvider.exportJvmInfo=true
+
diff --git a/pom.xml b/pom.xml
index abcf007..025fdf7 100755
--- a/pom.xml
+++ b/pom.xml
@@ -60,6 +60,7 @@
<module>zookeeper-docs</module>
<module>zookeeper-jute</module>
<module>zookeeper-server</module>
+ <module>zookeeper-metrics-providers</module>
<module>zookeeper-client</module>
<module>zookeeper-recipes</module>
<module>zookeeper-assembly</module>
diff --git a/zookeeper-assembly/pom.xml b/zookeeper-assembly/pom.xml
index c4e45ce..7586a3c 100755
--- a/zookeeper-assembly/pom.xml
+++ b/zookeeper-assembly/pom.xml
@@ -62,6 +62,11 @@
</dependency>
<dependency>
<groupId>org.apache.zookeeper</groupId>
+ <artifactId>zookeeper-prometheus-metrics</artifactId>
+ <version>${project.version}</version>
+ </dependency>
+ <dependency>
+ <groupId>org.apache.zookeeper</groupId>
<artifactId>zookeeper-recipes</artifactId>
<version>${project.version}</version>
<type>pom</type>
diff --git a/zookeeper-docs/src/main/resources/markdown/zookeeperAdmin.md
b/zookeeper-docs/src/main/resources/markdown/zookeeperAdmin.md
index d9f9703..a1ca0ef 100644
--- a/zookeeper-docs/src/main/resources/markdown/zookeeperAdmin.md
+++ b/zookeeper-docs/src/main/resources/markdown/zookeeperAdmin.md
@@ -1407,6 +1407,29 @@ options are used to configure the
[AdminServer](#sc_adminserver).
The URL for listing and issuing commands relative to the
root URL. Defaults to "/commands".
+### Metrics Providers
+
+**New in 3.6.0:** The following options are used to configure metrics.
+
+ By default ZooKeeper server exposes useful metrics using the
[AdminServer](#sc_adminserver).
+ and [Four Letter Words](#sc_4lw) interface.
+
+ Since 3.6.0 you can configure a different Metrics Provider, that exports
metrics
+ to your favourite system.
+
+ Since 3.6.0 ZooKeeper binary package bundles an integration with
[Prometheus.io](https://prometheus.io)
+
+* *metricsProvider.className* :
+ Set to "org.apache.zookeeper.metrics.prometheus.PrometheusMetricsProvider"
to
+ enable Prometheus.io exporter.
+
+* *metricsProvider.httpPort* :
+ Prometheus.io exporter will start a Jetty server and bind to this port, it
default to 7000.
+ Prometheus end point will be http://hostname:httPort/metrics.
+
+* *metricsProvider.exportJvmInfo* :
+ If this property is set to **true** Prometheus.io will export useful
metrics about the JVM.
+ The default is true.
<a name="Communication+using+the+Netty+framework"></a>
diff --git a/zookeeper-metrics-providers/pom.xml
b/zookeeper-metrics-providers/pom.xml
new file mode 100755
index 0000000..5c83792
--- /dev/null
+++ b/zookeeper-metrics-providers/pom.xml
@@ -0,0 +1,40 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0";
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/maven-v4_0_0.xsd";>
+ <!--
+ /**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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.
+ */
+ -->
+ <modelVersion>4.0.0</modelVersion>
+ <parent>
+ <groupId>org.apache.zookeeper</groupId>
+ <artifactId>parent</artifactId>
+ <version>3.6.0-SNAPSHOT</version>
+ <relativePath>..</relativePath>
+ </parent>
+
+ <groupId>org.apache.zookeeper</groupId>
+ <artifactId>zookeeper-metrics-providers</artifactId>
+ <packaging>pom</packaging>
+ <name>Apache ZooKeeper - Metrics Providers</name>
+ <description>ZooKeeper Metrics Providers</description>
+
+ <modules>
+ <module>zookeeper-prometheus-metrics</module>
+ </modules>
+
+</project>
diff --git a/zookeeper-metrics-providers/zookeeper-prometheus-metrics/pom.xml
b/zookeeper-metrics-providers/zookeeper-prometheus-metrics/pom.xml
new file mode 100755
index 0000000..d58e7e9
--- /dev/null
+++ b/zookeeper-metrics-providers/zookeeper-prometheus-metrics/pom.xml
@@ -0,0 +1,86 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0";
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/maven-v4_0_0.xsd";>
+ <!--
+ /**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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.
+ */
+ -->
+ <modelVersion>4.0.0</modelVersion>
+ <parent>
+ <groupId>org.apache.zookeeper</groupId>
+ <artifactId>zookeeper-metrics-providers</artifactId>
+ <version>3.6.0-SNAPSHOT</version>
+ <relativePath>..</relativePath>
+ </parent>
+
+ <groupId>org.apache.zookeeper</groupId>
+ <artifactId>zookeeper-prometheus-metrics</artifactId>
+ <packaging>jar</packaging>
+ <name>Apache ZooKeeper - Prometheus.io Metrics Provider</name>
+ <description>ZooKeeper Prometheus.io Metrics Provider
implementation</description>
+
+ <properties>
+ <prometheus.version>0.6.0</prometheus.version>
+ </properties>
+ <dependencies>
+ <dependency>
+ <groupId>org.apache.zookeeper</groupId>
+ <!-- we can create a metrics-providers-api package
+ once we get rid of ant based build
+ https://issues.apache.org/jira/browse/ZOOKEEPER-3376
+ -->
+ <artifactId>zookeeper</artifactId>
+ <version>${project.version}</version>
+ </dependency>
+ <dependency>
+ <groupId>io.prometheus</groupId>
+ <artifactId>simpleclient</artifactId>
+ <version>${prometheus.version}</version>
+ </dependency>
+ <dependency>
+ <groupId>io.prometheus</groupId>
+ <artifactId>simpleclient_hotspot</artifactId>
+ <version>${prometheus.version}</version>
+ </dependency>
+ <dependency>
+ <groupId>io.prometheus</groupId>
+ <artifactId>simpleclient_servlet</artifactId>
+ <version>${prometheus.version}</version>
+ </dependency>
+ <dependency>
+ <groupId>org.eclipse.jetty</groupId>
+ <artifactId>jetty-server</artifactId>
+ <scope>provided</scope>
+ </dependency>
+ <dependency>
+ <groupId>org.eclipse.jetty</groupId>
+ <artifactId>jetty-servlet</artifactId>
+ <scope>provided</scope>
+ </dependency>
+ <dependency>
+ <groupId>org.mockito</groupId>
+ <artifactId>mockito-core</artifactId>
+ <scope>test</scope>
+ </dependency>
+ <dependency>
+ <groupId>junit</groupId>
+ <artifactId>junit</artifactId>
+ <scope>test</scope>
+ </dependency>
+ </dependencies>
+
+</project>
diff --git
a/zookeeper-metrics-providers/zookeeper-prometheus-metrics/src/main/java/org/apache/zookeeper/metrics/prometheus/PrometheusMetricsProvider.java
b/zookeeper-metrics-providers/zookeeper-prometheus-metrics/src/main/java/org/apache/zookeeper/metrics/prometheus/PrometheusMetricsProvider.java
new file mode 100644
index 0000000..ffa9e5b
--- /dev/null
+++
b/zookeeper-metrics-providers/zookeeper-prometheus-metrics/src/main/java/org/apache/zookeeper/metrics/prometheus/PrometheusMetricsProvider.java
@@ -0,0 +1,412 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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 org.apache.zookeeper.metrics.prometheus;
+
+import io.prometheus.client.Collector;
+import io.prometheus.client.CollectorRegistry;
+import io.prometheus.client.exporter.MetricsServlet;
+import io.prometheus.client.hotspot.DefaultExports;
+import java.io.IOException;
+import java.util.Enumeration;
+import java.util.Objects;
+import java.util.Properties;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+import java.util.function.BiConsumer;
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import org.apache.zookeeper.metrics.Counter;
+import org.apache.zookeeper.metrics.Gauge;
+import org.apache.zookeeper.metrics.MetricsContext;
+import org.apache.zookeeper.metrics.MetricsProvider;
+import org.apache.zookeeper.metrics.MetricsProviderLifeCycleException;
+import org.apache.zookeeper.metrics.Summary;
+import org.apache.zookeeper.metrics.SummarySet;
+import org.eclipse.jetty.server.Server;
+import org.eclipse.jetty.servlet.ServletContextHandler;
+import org.eclipse.jetty.servlet.ServletHolder;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A Metrics Provider implementation based on https://prometheus.io.
+ *
+ * @since 3.6.0
+ */
+public class PrometheusMetricsProvider implements MetricsProvider {
+
+ private static final Logger LOG =
LoggerFactory.getLogger(PrometheusMetricsProvider.class);
+ private static final String LABEL = "key";
+ private static final String[] LABELS = {LABEL};
+ /**
+ * We are using the 'defaultRegistry'.
+ * <p>
+ * When you are running ZooKeeper (server or client) together with other
+ * libraries every metrics will be expected as a single view.
+ *
+ */
+ private final CollectorRegistry collectorRegistry =
CollectorRegistry.defaultRegistry;
+ private int port = 7000;
+ private boolean exportJvmInfo = true;
+ private Server server;
+ private final MetricsServletImpl servlet = new MetricsServletImpl();
+ private final Context rootContext = new Context();
+
+ @Override
+ public void configure(Properties configuration) throws
MetricsProviderLifeCycleException {
+ LOG.info("Initializing metrics, configuration: {}", configuration);
+ this.port = Integer.parseInt(configuration.getProperty("httpPort",
"7000"));
+ this.exportJvmInfo =
Boolean.parseBoolean(configuration.getProperty("exportJvmInfo", "true"));
+ }
+
+ @Override
+ public void start() throws MetricsProviderLifeCycleException {
+ try {
+ LOG.info("Starting /metrics HTTP endpoint at port {}
exportJvmInfo: {}", port, exportJvmInfo);
+ if (exportJvmInfo) {
+ DefaultExports.initialize();
+ }
+ server = new Server(port);
+ ServletContextHandler context = new ServletContextHandler();
+ context.setContextPath("/");
+ server.setHandler(context);
+ context.addServlet(new ServletHolder(servlet), "/metrics");
+ server.start();
+ } catch (Exception err) {
+ LOG.error("Cannot start /metrics server", err);
+ if (server != null) {
+ try {
+ server.stop();
+ } catch (Exception suppressed) {
+ err.addSuppressed(suppressed);
+ } finally {
+ server = null;
+ }
+ }
+ throw new MetricsProviderLifeCycleException(err);
+ }
+ }
+
+ // for tests
+ MetricsServletImpl getServlet() {
+ return servlet;
+ }
+
+ @Override
+ public MetricsContext getRootContext() {
+ return rootContext;
+ }
+
+ @Override
+ public void stop() {
+ if (server != null) {
+ try {
+ server.stop();
+ } catch (Exception err) {
+ LOG.error("Cannot safely stop Jetty server", err);
+ } finally {
+ server = null;
+ }
+ }
+ }
+
+ /**
+ * Dump all values to the 4lw interface and to the Admin server.
+ * <p>
+ * This method is not expected to be used to serve metrics to Prometheus.
We
+ * are using the MetricsServlet provided by Prometheus for that, leaving
the
+ * real representation to the Prometheus Java client.
+ *
+ * @param sink the receiver of data (4lw interface, Admin server or tests)
+ */
+ @Override
+ public void dump(BiConsumer<String, Object> sink) {
+ sampleGauges();
+ Enumeration<Collector.MetricFamilySamples> samplesFamilies =
collectorRegistry.metricFamilySamples();
+ while (samplesFamilies.hasMoreElements()) {
+ Collector.MetricFamilySamples samples =
samplesFamilies.nextElement();
+ samples.samples.forEach(sample -> {
+ String key = buildKeyForDump(sample);
+ sink.accept(key, sample.value);
+ });
+ }
+ }
+
+ private static String buildKeyForDump(Collector.MetricFamilySamples.Sample
sample) {
+ StringBuilder keyBuilder = new StringBuilder();
+ keyBuilder.append(sample.name);
+ if (sample.labelNames.size() > 0) {
+ keyBuilder.append('{');
+ for (int i = 0; i < sample.labelNames.size(); ++i) {
+ if (i > 0) {
+ keyBuilder.append(',');
+ }
+ keyBuilder.append(sample.labelNames.get(i));
+ keyBuilder.append("=\"");
+ keyBuilder.append(sample.labelValues.get(i));
+ keyBuilder.append('"');
+ }
+ keyBuilder.append('}');
+ }
+ return keyBuilder.toString();
+ }
+
+ /**
+ * Update Gauges. In ZooKeeper Metrics API Gauges are callbacks served by
+ * internal components and the value is not held by Prometheus structures.
+ */
+ private void sampleGauges() {
+ rootContext.gauges.values()
+ .forEach(PrometheusGaugeWrapper::sample);
+ }
+
+ @Override
+ public void resetAllValues() {
+ // not supported on Prometheus
+ }
+
+ private class Context implements MetricsContext {
+
+ private final ConcurrentMap<String, PrometheusGaugeWrapper> gauges =
new ConcurrentHashMap<>();
+ private final ConcurrentMap<String, PrometheusCounter> counters = new
ConcurrentHashMap<>();
+ private final ConcurrentMap<String, PrometheusSummary> basicSummaries
= new ConcurrentHashMap<>();
+ private final ConcurrentMap<String, PrometheusSummary> summaries = new
ConcurrentHashMap<>();
+ private final ConcurrentMap<String, PrometheusLabelledSummary>
basicSummarySets = new ConcurrentHashMap<>();
+ private final ConcurrentMap<String, PrometheusLabelledSummary>
summarySets = new ConcurrentHashMap<>();
+
+ @Override
+ public MetricsContext getContext(String name) {
+ // no hierarchy yet
+ return this;
+ }
+
+ @Override
+ public Counter getCounter(String name) {
+ return counters.computeIfAbsent(name, (n) -> {
+ return new PrometheusCounter(n);
+ });
+ }
+
+ /**
+ * Gauges may go up and down, in ZooKeeper they are a way to export
+ * internal values with a callback.
+ *
+ * @param name the name of the gauge
+ * @param gauge the callback
+ */
+ @Override
+ public void registerGauge(String name, Gauge gauge) {
+ Objects.requireNonNull(name);
+ gauges.compute(name, (id, prev) -> {
+ return new PrometheusGaugeWrapper(id, gauge,
+ prev != null ? prev.inner : null);
+ });
+ }
+
+ @Override
+ public void unregisterGauge(String name) {
+ PrometheusGaugeWrapper existing = gauges.remove(name);
+ if (existing != null) {
+ existing.unregister();
+ }
+ }
+
+ @Override
+ public Summary getSummary(String name, DetailLevel detailLevel) {
+ if (detailLevel == DetailLevel.BASIC) {
+ return basicSummaries.computeIfAbsent(name, (n) -> {
+ if (summaries.containsKey(n)) {
+ throw new IllegalArgumentException("Already registered
a non basic summary as " + n);
+ }
+ return new PrometheusSummary(name, detailLevel);
+ });
+ } else {
+ return summaries.computeIfAbsent(name, (n) -> {
+ if (basicSummaries.containsKey(n)) {
+ throw new IllegalArgumentException("Already registered
a basic summary as " + n);
+ }
+ return new PrometheusSummary(name, detailLevel);
+ });
+ }
+ }
+
+ @Override
+ public SummarySet getSummarySet(String name, DetailLevel detailLevel) {
+ if (detailLevel == DetailLevel.BASIC) {
+ return basicSummarySets.computeIfAbsent(name, (n) -> {
+ if (summarySets.containsKey(n)) {
+ throw new IllegalArgumentException("Already registered
a non basic summary set as " + n);
+ }
+ return new PrometheusLabelledSummary(name, detailLevel);
+ });
+ } else {
+ return summarySets.computeIfAbsent(name, (n) -> {
+ if (basicSummarySets.containsKey(n)) {
+ throw new IllegalArgumentException("Already registered
a basic summary set as " + n);
+ }
+ return new PrometheusLabelledSummary(name, detailLevel);
+ });
+ }
+ }
+
+ }
+
+ private class PrometheusCounter implements Counter {
+
+ private final io.prometheus.client.Counter inner;
+ private final String name;
+
+ public PrometheusCounter(String name) {
+ this.name = name;
+ this.inner = io.prometheus.client.Counter
+ .build(name, name)
+ .register(collectorRegistry);
+ }
+
+ @Override
+ public void add(long delta) {
+ try {
+ inner.inc(delta);
+ } catch (IllegalArgumentException err) {
+ LOG.error("invalid delta " + delta + " for metric " + name,
err);
+ }
+ }
+
+ @Override
+ public long get() {
+ // this method is used only for tests
+ // Prometheus returns a "double"
+ // it is safe to fine to a long
+ // we are never setting non-integer values
+ return (long) inner.get();
+ }
+
+ }
+
+ private class PrometheusGaugeWrapper {
+
+ private final io.prometheus.client.Gauge inner;
+ private final Gauge gauge;
+ private final String name;
+
+ public PrometheusGaugeWrapper(String name, Gauge gauge,
io.prometheus.client.Gauge prev) {
+ this.name = name;
+ this.gauge = gauge;
+ this.inner = prev != null ? prev
+ : io.prometheus.client.Gauge
+ .build(name, name)
+ .register(collectorRegistry);
+ }
+
+ /**
+ * Call the callack and update Prometheus Gauge. This method is called
+ * when the server is polling for a value.
+ */
+ private void sample() {
+ Number value = gauge.get();
+ this.inner.set(value != null ? value.doubleValue() : 0);
+ }
+
+ private void unregister() {
+ collectorRegistry.unregister(inner);
+ }
+
+ }
+
+ private class PrometheusSummary implements Summary {
+
+ private final io.prometheus.client.Summary inner;
+ private final String name;
+
+ public PrometheusSummary(String name, MetricsContext.DetailLevel
level) {
+ this.name = name;
+ if (level == MetricsContext.DetailLevel.ADVANCED) {
+ this.inner = io.prometheus.client.Summary
+ .build(name, name)
+ .quantile(0.5, 0.05) // Add 50th percentile (= median)
with 5% tolerated error
+ .quantile(0.9, 0.01) // Add 90th percentile with 1%
tolerated error
+ .quantile(0.99, 0.001) // Add 99th percentile with
0.1% tolerated error
+ .register(collectorRegistry);
+ } else {
+ this.inner = io.prometheus.client.Summary
+ .build(name, name)
+ .quantile(0.5, 0.05) // Add 50th percentile (= median)
with 5% tolerated error
+ .register(collectorRegistry);
+ }
+ }
+
+ @Override
+ public void add(long delta) {
+ try {
+ inner.observe(delta);
+ } catch (IllegalArgumentException err) {
+ LOG.error("invalid delta " + delta + " for metric " + name,
err);
+ }
+ }
+
+ }
+
+ private class PrometheusLabelledSummary implements SummarySet {
+
+ private final io.prometheus.client.Summary inner;
+ private final String name;
+
+ public PrometheusLabelledSummary(String name,
MetricsContext.DetailLevel level) {
+ this.name = name;
+ if (level == MetricsContext.DetailLevel.ADVANCED) {
+ this.inner = io.prometheus.client.Summary
+ .build(name, name)
+ .labelNames(LABELS)
+ .quantile(0.5, 0.05) // Add 50th percentile (= median)
with 5% tolerated error
+ .quantile(0.9, 0.01) // Add 90th percentile with 1%
tolerated error
+ .quantile(0.99, 0.001) // Add 99th percentile with
0.1% tolerated error
+ .register(collectorRegistry);
+ } else {
+ this.inner = io.prometheus.client.Summary
+ .build(name, name)
+ .labelNames(LABELS)
+ .quantile(0.5, 0.05) // Add 50th percentile (= median)
with 5% tolerated error
+ .register(collectorRegistry);
+ }
+ }
+
+ @Override
+ public void add(String key, long value) {
+ try {
+ inner.labels(key).observe(value);
+ } catch (IllegalArgumentException err) {
+ LOG.error("invalid value " + value + " for metric " + name + "
with key " + key, err);
+ }
+ }
+
+ }
+
+ class MetricsServletImpl extends MetricsServlet {
+
+ @Override
+ protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
+ // little trick: update the Gauges before serving data
+ // from Prometheus CollectorRegistry
+ sampleGauges();
+ // serve data using Prometheus built in client.
+ super.doGet(req, resp);
+ }
+ }
+}
diff --git
a/zookeeper-metrics-providers/zookeeper-prometheus-metrics/src/test/java/org/apache/zookeeper/metrics/prometheus/ExportJvmInfoTest.java
b/zookeeper-metrics-providers/zookeeper-prometheus-metrics/src/test/java/org/apache/zookeeper/metrics/prometheus/ExportJvmInfoTest.java
new file mode 100644
index 0000000..899a271
--- /dev/null
+++
b/zookeeper-metrics-providers/zookeeper-prometheus-metrics/src/test/java/org/apache/zookeeper/metrics/prometheus/ExportJvmInfoTest.java
@@ -0,0 +1,60 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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 org.apache.zookeeper.metrics.prometheus;
+
+import io.prometheus.client.CollectorRegistry;
+import java.util.Properties;
+import static org.junit.Assert.assertEquals;
+import org.junit.Test;
+
+/**
+ * Tests about Prometheus Metrics Provider. Please note that we are not testing
+ * Prometheus but our integration.
+ */
+public class ExportJvmInfoTest {
+
+ @Test
+ public void exportInfo() throws Exception {
+ runTest(true);
+ }
+
+ @Test
+ public void doNotExportInfo() throws Exception {
+ runTest(false);
+ }
+
+ private void runTest(boolean exportJvmInfo) throws Exception {
+ CollectorRegistry.defaultRegistry.clear();
+ PrometheusMetricsProvider provider = new PrometheusMetricsProvider();
+ try {
+ Properties configuration = new Properties();
+ configuration.setProperty("httpPort", "0"); // ephemeral port
+ configuration.setProperty("exportJvmInfo", exportJvmInfo + "");
+ provider.configure(configuration);
+ provider.start();
+ boolean[] found = {false};
+ provider.dump((k, v) -> {
+ found[0] = found[0] || k.contains("heap");
+ });
+ assertEquals(exportJvmInfo, found[0]);
+ } finally {
+ provider.stop();
+ }
+ }
+
+}
diff --git
a/zookeeper-metrics-providers/zookeeper-prometheus-metrics/src/test/java/org/apache/zookeeper/metrics/prometheus/PrometheusMetricsProviderTest.java
b/zookeeper-metrics-providers/zookeeper-prometheus-metrics/src/test/java/org/apache/zookeeper/metrics/prometheus/PrometheusMetricsProviderTest.java
new file mode 100644
index 0000000..b52bd7b
--- /dev/null
+++
b/zookeeper-metrics-providers/zookeeper-prometheus-metrics/src/test/java/org/apache/zookeeper/metrics/prometheus/PrometheusMetricsProviderTest.java
@@ -0,0 +1,295 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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 org.apache.zookeeper.metrics.prometheus;
+
+import io.prometheus.client.CollectorRegistry;
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.io.StringWriter;
+import java.util.Properties;
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import org.apache.zookeeper.metrics.Counter;
+import org.apache.zookeeper.metrics.Gauge;
+import org.apache.zookeeper.metrics.MetricsContext;
+import org.apache.zookeeper.metrics.Summary;
+import org.hamcrest.CoreMatchers;
+import static org.hamcrest.CoreMatchers.containsString;
+import org.junit.After;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertSame;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+import org.junit.Before;
+import org.junit.Test;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+/**
+ * Tests about Prometheus Metrics Provider. Please note that we are not testing
+ * Prometheus but only our integration.
+ */
+public class PrometheusMetricsProviderTest {
+
+ private PrometheusMetricsProvider provider;
+
+ @Before
+ public void setup() throws Exception {
+ CollectorRegistry.defaultRegistry.clear();
+ provider = new PrometheusMetricsProvider();
+ Properties configuration = new Properties();
+ configuration.setProperty("httpPort", "0"); // ephemeral port
+ configuration.setProperty("exportJvmInfo", "false");
+ provider.configure(configuration);
+ provider.start();
+ }
+
+ @After
+ public void tearDown() {
+ if (provider != null) {
+ provider.stop();
+ }
+ CollectorRegistry.defaultRegistry.clear();
+ }
+
+ @Test
+ public void testCounters() throws Exception {
+ Counter counter = provider.getRootContext().getCounter("cc");
+ counter.add(10);
+ int[] count = {0};
+ provider.dump((k, v) -> {
+ assertEquals("cc", k);
+ assertEquals(10, ((Number) v).intValue());
+ count[0]++;
+ }
+ );
+ assertEquals(1, count[0]);
+ count[0] = 0;
+
+ // this is not allowed but it must not throw errors
+ counter.add(-1);
+
+ provider.dump((k, v) -> {
+ assertEquals("cc", k);
+ assertEquals(10, ((Number) v).intValue());
+ count[0]++;
+ }
+ );
+ assertEquals(1, count[0]);
+
+ // we always must get the same object
+ assertSame(counter, provider.getRootContext().getCounter("cc"));
+
+ String res = callServlet();
+ assertThat(res, CoreMatchers.containsString("# TYPE cc counter"));
+ assertThat(res, CoreMatchers.containsString("cc 10.0"));
+ }
+
+ @Test
+ public void testGauge() throws Exception {
+ int[] values = {78, -89};
+ int[] callCounts = {0, 0};
+ Gauge gauge0 = () -> {
+ callCounts[0]++;
+ return values[0];
+ };
+ Gauge gauge1 = () -> {
+ callCounts[1]++;
+ return values[1];
+ };
+ provider.getRootContext().registerGauge("gg", gauge0);
+
+ int[] count = {0};
+ provider.dump((k, v) -> {
+ assertEquals("gg", k);
+ assertEquals(values[0], ((Number) v).intValue());
+ count[0]++;
+ }
+ );
+ assertEquals(1, callCounts[0]);
+ assertEquals(0, callCounts[1]);
+ assertEquals(1, count[0]);
+ count[0] = 0;
+ String res2 = callServlet();
+ assertThat(res2, CoreMatchers.containsString("# TYPE gg gauge"));
+ assertThat(res2, CoreMatchers.containsString("gg 78.0"));
+
+ provider.getRootContext().unregisterGauge("gg");
+ provider.dump((k, v) -> {
+ count[0]++;
+ }
+ );
+ assertEquals(2, callCounts[0]);
+ assertEquals(0, callCounts[1]);
+ assertEquals(0, count[0]);
+ String res3 = callServlet();
+ assertTrue(res3.isEmpty());
+
+ provider.getRootContext().registerGauge("gg", gauge1);
+
+ provider.dump((k, v) -> {
+ assertEquals("gg", k);
+ assertEquals(values[1], ((Number) v).intValue());
+ count[0]++;
+ }
+ );
+ assertEquals(2, callCounts[0]);
+ assertEquals(1, callCounts[1]);
+ assertEquals(1, count[0]);
+ count[0] = 0;
+
+ String res4 = callServlet();
+ assertThat(res4, CoreMatchers.containsString("# TYPE gg gauge"));
+ assertThat(res4, CoreMatchers.containsString("gg -89.0"));
+ assertEquals(2, callCounts[0]);
+ // the servlet must sample the value again (from gauge1)
+ assertEquals(2, callCounts[1]);
+
+ // override gauge, without unregister
+ provider.getRootContext().registerGauge("gg", gauge0);
+
+ provider.dump((k, v) -> {
+ count[0]++;
+ }
+ );
+ assertEquals(1, count[0]);
+ assertEquals(3, callCounts[0]);
+ assertEquals(2, callCounts[1]);
+ }
+
+ @Test
+ public void testBasicSummary() throws Exception {
+ Summary summary = provider.getRootContext()
+ .getSummary("cc", MetricsContext.DetailLevel.BASIC);
+ summary.add(10);
+ summary.add(10);
+ int[] count = {0};
+ provider.dump((k, v) -> {
+ count[0]++;
+ int value = ((Number) v).intValue();
+
+ switch (k) {
+ case "cc{quantile=\"0.5\"}":
+ assertEquals(10, value);
+ break;
+ case "cc_count":
+ assertEquals(2, value);
+ break;
+ case "cc_sum":
+ assertEquals(20, value);
+ break;
+ default:
+ fail("unespected key " + k);
+ break;
+ }
+ }
+ );
+ assertEquals(3, count[0]);
+ count[0] = 0;
+
+ // we always must get the same object
+ assertSame(summary, provider.getRootContext()
+ .getSummary("cc", MetricsContext.DetailLevel.BASIC));
+
+ try {
+ provider.getRootContext()
+ .getSummary("cc", MetricsContext.DetailLevel.ADVANCED);
+ fail("Can't get the same summary with a different DetailLevel");
+ } catch (IllegalArgumentException err) {
+ assertThat(err.getMessage(), containsString("Already registered"));
+ }
+
+ String res = callServlet();
+ assertThat(res, containsString("# TYPE cc summary"));
+ assertThat(res, CoreMatchers.containsString("cc_sum 20.0"));
+ assertThat(res, CoreMatchers.containsString("cc_count 2.0"));
+ assertThat(res, CoreMatchers.containsString("cc{quantile=\"0.5\",}
10.0"));
+ }
+
+ @Test
+ public void testAdvancedSummary() throws Exception {
+ Summary summary = provider.getRootContext()
+ .getSummary("cc", MetricsContext.DetailLevel.ADVANCED);
+ summary.add(10);
+ summary.add(10);
+ int[] count = {0};
+ provider.dump((k, v) -> {
+ count[0]++;
+ int value = ((Number) v).intValue();
+
+ switch (k) {
+ case "cc{quantile=\"0.5\"}":
+ assertEquals(10, value);
+ break;
+ case "cc{quantile=\"0.9\"}":
+ assertEquals(10, value);
+ break;
+ case "cc{quantile=\"0.99\"}":
+ assertEquals(10, value);
+ break;
+ case "cc_count":
+ assertEquals(2, value);
+ break;
+ case "cc_sum":
+ assertEquals(20, value);
+ break;
+ default:
+ fail("unespected key " + k);
+ break;
+ }
+ }
+ );
+ assertEquals(5, count[0]);
+ count[0] = 0;
+
+ // we always must get the same object
+ assertSame(summary, provider.getRootContext()
+ .getSummary("cc", MetricsContext.DetailLevel.ADVANCED));
+
+ try {
+ provider.getRootContext()
+ .getSummary("cc", MetricsContext.DetailLevel.BASIC);
+ fail("Can't get the same summary with a different DetailLevel");
+ } catch (IllegalArgumentException err) {
+ assertThat(err.getMessage(), containsString("Already registered"));
+ }
+
+ String res = callServlet();
+ assertThat(res, containsString("# TYPE cc summary"));
+ assertThat(res, CoreMatchers.containsString("cc_sum 20.0"));
+ assertThat(res, CoreMatchers.containsString("cc_count 2.0"));
+ assertThat(res, CoreMatchers.containsString("cc{quantile=\"0.5\",}
10.0"));
+ assertThat(res, CoreMatchers.containsString("cc{quantile=\"0.9\",}
10.0"));
+ assertThat(res, CoreMatchers.containsString("cc{quantile=\"0.99\",}
10.0"));
+ }
+
+ private String callServlet() throws ServletException, IOException {
+ // we are not performing an HTTP request
+ // but we are calling directly the servlet
+ StringWriter writer = new StringWriter();
+ HttpServletResponse response = mock(HttpServletResponse.class);
+ when(response.getWriter()).thenReturn(new PrintWriter(writer));
+ HttpServletRequest req = mock(HttpServletRequest.class);
+ provider.getServlet().doGet(req, response);
+ String res = writer.toString();
+ return res;
+ }
+
+}
diff --git
a/zookeeper-metrics-providers/zookeeper-prometheus-metrics/src/test/resources/log4j.properties
b/zookeeper-metrics-providers/zookeeper-prometheus-metrics/src/test/resources/log4j.properties
new file mode 100644
index 0000000..4a2ede9
--- /dev/null
+++
b/zookeeper-metrics-providers/zookeeper-prometheus-metrics/src/test/resources/log4j.properties
@@ -0,0 +1,65 @@
+# Copyright 2012 The Apache Software Foundation
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements. See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership. The ASF licenses this file
+# to you 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.
+
+# Define some default values that can be overridden by system properties
+zookeeper.root.logger=INFO, CONSOLE
+
+zookeeper.console.threshold=INFO
+
+zookeeper.log.dir=.
+zookeeper.log.file=zookeeper.log
+zookeeper.log.threshold=INFO
+zookeeper.log.maxfilesize=256MB
+zookeeper.log.maxbackupindex=20
+
+zookeeper.tracelog.dir=${zookeeper.log.dir}
+zookeeper.tracelog.file=zookeeper_trace.log
+
+log4j.rootLogger=${zookeeper.root.logger}
+
+#
+# console
+# Add "console" to rootlogger above if you want to use this
+#
+log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
+log4j.appender.CONSOLE.Threshold=${zookeeper.console.threshold}
+log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
+log4j.appender.CONSOLE.layout.ConversionPattern=%d{ISO8601} [myid:%X{myid}] -
%-5p [%t:%C{1}@%L] - %m%n
+
+#
+# Add ROLLINGFILE to rootLogger to get log file output
+#
+log4j.appender.ROLLINGFILE=org.apache.log4j.RollingFileAppender
+log4j.appender.ROLLINGFILE.Threshold=${zookeeper.log.threshold}
+log4j.appender.ROLLINGFILE.File=${zookeeper.log.dir}/${zookeeper.log.file}
+log4j.appender.ROLLINGFILE.MaxFileSize=${zookeeper.log.maxfilesize}
+log4j.appender.ROLLINGFILE.MaxBackupIndex=${zookeeper.log.maxbackupindex}
+log4j.appender.ROLLINGFILE.layout=org.apache.log4j.PatternLayout
+log4j.appender.ROLLINGFILE.layout.ConversionPattern=%d{ISO8601}
[myid:%X{myid}] - %-5p [%t:%C{1}@%L] - %m%n
+
+#
+# Add TRACEFILE to rootLogger to get log file output
+# Log TRACE level and above messages to a log file
+#
+log4j.appender.TRACEFILE=org.apache.log4j.FileAppender
+log4j.appender.TRACEFILE.Threshold=TRACE
+log4j.appender.TRACEFILE.File=${zookeeper.tracelog.dir}/${zookeeper.tracelog.file}
+
+log4j.appender.TRACEFILE.layout=org.apache.log4j.PatternLayout
+### Notice we are including log4j's NDC here (%x)
+log4j.appender.TRACEFILE.layout.ConversionPattern=%d{ISO8601} [myid:%X{myid}]
- %-5p [%t:%C{1}@%L][%x] - %m%n
diff --git
a/zookeeper-server/src/main/resources/lib/simpleclient-0.6.0.LICENSE.txt
b/zookeeper-server/src/main/resources/lib/simpleclient-0.6.0.LICENSE.txt
new file mode 100644
index 0000000..6279e52
--- /dev/null
+++ b/zookeeper-server/src/main/resources/lib/simpleclient-0.6.0.LICENSE.txt
@@ -0,0 +1,202 @@
+
+ Apache License
+ Version 2.0, January 2004
+ http://www.apache.org/licenses/
+
+ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+ 1. Definitions.
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diff --git
a/zookeeper-server/src/main/resources/lib/simpleclient_common-0.6.0_LICENSE.txt
b/zookeeper-server/src/main/resources/lib/simpleclient_common-0.6.0_LICENSE.txt
new file mode 100644
index 0000000..6279e52
--- /dev/null
+++
b/zookeeper-server/src/main/resources/lib/simpleclient_common-0.6.0_LICENSE.txt
@@ -0,0 +1,202 @@
+
+ Apache License
+ Version 2.0, January 2004
+ http://www.apache.org/licenses/
+
+ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+ 1. Definitions.
+
+ "License" shall mean the terms and conditions for use, reproduction,
+ and distribution as defined by Sections 1 through 9 of this document.
+
+ "Licensor" shall mean the copyright owner or entity authorized by
+ the copyright owner that is granting the License.
+
+ "Legal Entity" shall mean the union of the acting entity and all
+ other entities that control, are controlled by, or are under common
+ control with that entity. For the purposes of this definition,
+ "control" means (i) the power, direct or indirect, to cause the
+ direction or management of such entity, whether by contract or
+ otherwise, or (ii) ownership of fifty percent (50%) or more of the
+ outstanding shares, or (iii) beneficial ownership of such entity.
+
+ "You" (or "Your") shall mean an individual or Legal Entity
+ exercising permissions granted by this License.
+
+ "Source" form shall mean the preferred form for making modifications,
+ including but not limited to software source code, documentation
+ source, and configuration files.
+
+ "Object" form shall mean any form resulting from mechanical
+ transformation or translation of a Source form, including but
+ not limited to compiled object code, generated documentation,
+ and conversions to other media types.
+
+ "Work" shall mean the work of authorship, whether in Source or
+ Object form, made available under the License, as indicated by a
+ copyright notice that is included in or attached to the work
+ (an example is provided in the Appendix below).
+
+ "Derivative Works" shall mean any work, whether in Source or Object
+ form, that is based on (or derived from) the Work and for which the
+ editorial revisions, annotations, elaborations, or other modifications
+ represent, as a whole, an original work of authorship. For the purposes
+ of this License, Derivative Works shall not include works that remain
+ separable from, or merely link (or bind by name) to the interfaces of,
+ the Work and Derivative Works thereof.
+
+ "Contribution" shall mean any work of authorship, including
+ the original version of the Work and any modifications or additions
+ to that Work or Derivative Works thereof, that is intentionally
+ submitted to Licensor for inclusion in the Work by the copyright owner
+ or by an individual or Legal Entity authorized to submit on behalf of
+ the copyright owner. For the purposes of this definition, "submitted"
+ means any form of electronic, verbal, or written communication sent
+ to the Licensor or its representatives, including but not limited to
+ communication on electronic mailing lists, source code control systems,
+ and issue tracking systems that are managed by, or on behalf of, the
+ Licensor for the purpose of discussing and improving the Work, but
+ excluding communication that is conspicuously marked or otherwise
+ designated in writing by the copyright owner as "Not a Contribution."
+
+ "Contributor" shall mean Licensor and any individual or Legal Entity
+ on behalf of whom a Contribution has been received by Licensor and
+ subsequently incorporated within the Work.
+
+ 2. Grant of Copyright License. Subject to the terms and conditions of
+ this License, each Contributor hereby grants to You a perpetual,
+ worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+ copyright license to reproduce, prepare Derivative Works of,
+ publicly display, publicly perform, sublicense, and distribute the
+ Work and such Derivative Works in Source or Object form.
+
+ 3. Grant of Patent License. Subject to the terms and conditions of
+ this License, each Contributor hereby grants to You a perpetual,
+ worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+ (except as stated in this section) patent license to make, have made,
+ use, offer to sell, sell, import, and otherwise transfer the Work,
+ where such license applies only to those patent claims licensable
+ by such Contributor that are necessarily infringed by their
+ Contribution(s) alone or by combination of their Contribution(s)
+ with the Work to which such Contribution(s) was submitted. If You
+ institute patent litigation against any entity (including a
+ cross-claim or counterclaim in a lawsuit) alleging that the Work
+ or a Contribution incorporated within the Work constitutes direct
+ or contributory patent infringement, then any patent licenses
+ granted to You under this License for that Work shall terminate
+ as of the date such litigation is filed.
+
+ 4. Redistribution. You may reproduce and distribute copies of the
+ Work or Derivative Works thereof in any medium, with or without
+ modifications, and in Source or Object form, provided that You
+ meet the following conditions:
+
+ (a) You must give any other recipients of the Work or
+ Derivative Works a copy of this License; and
+
+ (b) You must cause any modified files to carry prominent notices
+ stating that You changed the files; and
+
+ (c) You must retain, in the Source form of any Derivative Works
+ that You distribute, all copyright, patent, trademark, and
+ attribution notices from the Source form of the Work,
+ excluding those notices that do not pertain to any part of
+ the Derivative Works; and
+
+ (d) If the Work includes a "NOTICE" text file as part of its
+ distribution, then any Derivative Works that You distribute must
+ include a readable copy of the attribution notices contained
+ within such NOTICE file, excluding those notices that do not
+ pertain to any part of the Derivative Works, in at least one
+ of the following places: within a NOTICE text file distributed
+ as part of the Derivative Works; within the Source form or
+ documentation, if provided along with the Derivative Works; or,
+ within a display generated by the Derivative Works, if and
+ wherever such third-party notices normally appear. The contents
+ of the NOTICE file are for informational purposes only and
+ do not modify the License. You may add Your own attribution
+ notices within Derivative Works that You distribute, alongside
+ or as an addendum to the NOTICE text from the Work, provided
+ that such additional attribution notices cannot be construed
+ as modifying the License.
+
+ You may add Your own copyright statement to Your modifications and
+ may provide additional or different license terms and conditions
+ for use, reproduction, or distribution of Your modifications, or
+ for any such Derivative Works as a whole, provided Your use,
+ reproduction, and distribution of the Work otherwise complies with
+ the conditions stated in this License.
+
+ 5. Submission of Contributions. Unless You explicitly state otherwise,
+ any Contribution intentionally submitted for inclusion in the Work
+ by You to the Licensor shall be under the terms and conditions of
+ this License, without any additional terms or conditions.
+ Notwithstanding the above, nothing herein shall supersede or modify
+ the terms of any separate license agreement you may have executed
+ with Licensor regarding such Contributions.
+
+ 6. Trademarks. This License does not grant permission to use the trade
+ names, trademarks, service marks, or product names of the Licensor,
+ except as required for reasonable and customary use in describing the
+ origin of the Work and reproducing the content of the NOTICE file.
+
+ 7. Disclaimer of Warranty. Unless required by applicable law or
+ agreed to in writing, Licensor provides the Work (and each
+ Contributor provides its Contributions) on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+ implied, including, without limitation, any warranties or conditions
+ of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+ PARTICULAR PURPOSE. You are solely responsible for determining the
+ appropriateness of using or redistributing the Work and assume any
+ risks associated with Your exercise of permissions under this License.
+
+ 8. Limitation of Liability. In no event and under no legal theory,
+ whether in tort (including negligence), contract, or otherwise,
+ unless required by applicable law (such as deliberate and grossly
+ negligent acts) or agreed to in writing, shall any Contributor be
+ liable to You for damages, including any direct, indirect, special,
+ incidental, or consequential damages of any character arising as a
+ result of this License or out of the use or inability to use the
+ Work (including but not limited to damages for loss of goodwill,
+ work stoppage, computer failure or malfunction, or any and all
+ other commercial damages or losses), even if such Contributor
+ has been advised of the possibility of such damages.
+
+ 9. Accepting Warranty or Additional Liability. While redistributing
+ the Work or Derivative Works thereof, You may choose to offer,
+ and charge a fee for, acceptance of support, warranty, indemnity,
+ or other liability obligations and/or rights consistent with this
+ License. However, in accepting such obligations, You may act only
+ on Your own behalf and on Your sole responsibility, not on behalf
+ of any other Contributor, and only if You agree to indemnify,
+ defend, and hold each Contributor harmless for any liability
+ incurred by, or claims asserted against, such Contributor by reason
+ of your accepting any such warranty or additional liability.
+
+ END OF TERMS AND CONDITIONS
+
+ APPENDIX: How to apply the Apache License to your work.
+
+ To apply the Apache License to your work, attach the following
+ boilerplate notice, with the fields enclosed by brackets "[]"
+ replaced with your own identifying information. (Don't include
+ the brackets!) The text should be enclosed in the appropriate
+ comment syntax for the file format. We also recommend that a
+ file or class name and description of purpose be included on the
+ same "printed page" as the copyright notice for easier
+ identification within third-party archives.
+
+ Copyright 1999-2005 The Apache Software Foundation
+
+ 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.
diff --git
a/zookeeper-server/src/main/resources/lib/simpleclient_hotspot-0.6.0_LICENSE.txt
b/zookeeper-server/src/main/resources/lib/simpleclient_hotspot-0.6.0_LICENSE.txt
new file mode 100644
index 0000000..6279e52
--- /dev/null
+++
b/zookeeper-server/src/main/resources/lib/simpleclient_hotspot-0.6.0_LICENSE.txt
@@ -0,0 +1,202 @@
+
+ Apache License
+ Version 2.0, January 2004
+ http://www.apache.org/licenses/
+
+ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+ 1. Definitions.
+
+ "License" shall mean the terms and conditions for use, reproduction,
+ and distribution as defined by Sections 1 through 9 of this document.
+
+ "Licensor" shall mean the copyright owner or entity authorized by
+ the copyright owner that is granting the License.
+
+ "Legal Entity" shall mean the union of the acting entity and all
+ other entities that control, are controlled by, or are under common
+ control with that entity. For the purposes of this definition,
+ "control" means (i) the power, direct or indirect, to cause the
+ direction or management of such entity, whether by contract or
+ otherwise, or (ii) ownership of fifty percent (50%) or more of the
+ outstanding shares, or (iii) beneficial ownership of such entity.
+
+ "You" (or "Your") shall mean an individual or Legal Entity
+ exercising permissions granted by this License.
+
+ "Source" form shall mean the preferred form for making modifications,
+ including but not limited to software source code, documentation
+ source, and configuration files.
+
+ "Object" form shall mean any form resulting from mechanical
+ transformation or translation of a Source form, including but
+ not limited to compiled object code, generated documentation,
+ and conversions to other media types.
+
+ "Work" shall mean the work of authorship, whether in Source or
+ Object form, made available under the License, as indicated by a
+ copyright notice that is included in or attached to the work
+ (an example is provided in the Appendix below).
+
+ "Derivative Works" shall mean any work, whether in Source or Object
+ form, that is based on (or derived from) the Work and for which the
+ editorial revisions, annotations, elaborations, or other modifications
+ represent, as a whole, an original work of authorship. For the purposes
+ of this License, Derivative Works shall not include works that remain
+ separable from, or merely link (or bind by name) to the interfaces of,
+ the Work and Derivative Works thereof.
+
+ "Contribution" shall mean any work of authorship, including
+ the original version of the Work and any modifications or additions
+ to that Work or Derivative Works thereof, that is intentionally
+ submitted to Licensor for inclusion in the Work by the copyright owner
+ or by an individual or Legal Entity authorized to submit on behalf of
+ the copyright owner. For the purposes of this definition, "submitted"
+ means any form of electronic, verbal, or written communication sent
+ to the Licensor or its representatives, including but not limited to
+ communication on electronic mailing lists, source code control systems,
+ and issue tracking systems that are managed by, or on behalf of, the
+ Licensor for the purpose of discussing and improving the Work, but
+ excluding communication that is conspicuously marked or otherwise
+ designated in writing by the copyright owner as "Not a Contribution."
+
+ "Contributor" shall mean Licensor and any individual or Legal Entity
+ on behalf of whom a Contribution has been received by Licensor and
+ subsequently incorporated within the Work.
+
+ 2. Grant of Copyright License. Subject to the terms and conditions of
+ this License, each Contributor hereby grants to You a perpetual,
+ worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+ copyright license to reproduce, prepare Derivative Works of,
+ publicly display, publicly perform, sublicense, and distribute the
+ Work and such Derivative Works in Source or Object form.
+
+ 3. Grant of Patent License. Subject to the terms and conditions of
+ this License, each Contributor hereby grants to You a perpetual,
+ worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+ (except as stated in this section) patent license to make, have made,
+ use, offer to sell, sell, import, and otherwise transfer the Work,
+ where such license applies only to those patent claims licensable
+ by such Contributor that are necessarily infringed by their
+ Contribution(s) alone or by combination of their Contribution(s)
+ with the Work to which such Contribution(s) was submitted. If You
+ institute patent litigation against any entity (including a
+ cross-claim or counterclaim in a lawsuit) alleging that the Work
+ or a Contribution incorporated within the Work constitutes direct
+ or contributory patent infringement, then any patent licenses
+ granted to You under this License for that Work shall terminate
+ as of the date such litigation is filed.
+
+ 4. Redistribution. You may reproduce and distribute copies of the
+ Work or Derivative Works thereof in any medium, with or without
+ modifications, and in Source or Object form, provided that You
+ meet the following conditions:
+
+ (a) You must give any other recipients of the Work or
+ Derivative Works a copy of this License; and
+
+ (b) You must cause any modified files to carry prominent notices
+ stating that You changed the files; and
+
+ (c) You must retain, in the Source form of any Derivative Works
+ that You distribute, all copyright, patent, trademark, and
+ attribution notices from the Source form of the Work,
+ excluding those notices that do not pertain to any part of
+ the Derivative Works; and
+
+ (d) If the Work includes a "NOTICE" text file as part of its
+ distribution, then any Derivative Works that You distribute must
+ include a readable copy of the attribution notices contained
+ within such NOTICE file, excluding those notices that do not
+ pertain to any part of the Derivative Works, in at least one
+ of the following places: within a NOTICE text file distributed
+ as part of the Derivative Works; within the Source form or
+ documentation, if provided along with the Derivative Works; or,
+ within a display generated by the Derivative Works, if and
+ wherever such third-party notices normally appear. The contents
+ of the NOTICE file are for informational purposes only and
+ do not modify the License. You may add Your own attribution
+ notices within Derivative Works that You distribute, alongside
+ or as an addendum to the NOTICE text from the Work, provided
+ that such additional attribution notices cannot be construed
+ as modifying the License.
+
+ You may add Your own copyright statement to Your modifications and
+ may provide additional or different license terms and conditions
+ for use, reproduction, or distribution of Your modifications, or
+ for any such Derivative Works as a whole, provided Your use,
+ reproduction, and distribution of the Work otherwise complies with
+ the conditions stated in this License.
+
+ 5. Submission of Contributions. Unless You explicitly state otherwise,
+ any Contribution intentionally submitted for inclusion in the Work
+ by You to the Licensor shall be under the terms and conditions of
+ this License, without any additional terms or conditions.
+ Notwithstanding the above, nothing herein shall supersede or modify
+ the terms of any separate license agreement you may have executed
+ with Licensor regarding such Contributions.
+
+ 6. Trademarks. This License does not grant permission to use the trade
+ names, trademarks, service marks, or product names of the Licensor,
+ except as required for reasonable and customary use in describing the
+ origin of the Work and reproducing the content of the NOTICE file.
+
+ 7. Disclaimer of Warranty. Unless required by applicable law or
+ agreed to in writing, Licensor provides the Work (and each
+ Contributor provides its Contributions) on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+ implied, including, without limitation, any warranties or conditions
+ of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+ PARTICULAR PURPOSE. You are solely responsible for determining the
+ appropriateness of using or redistributing the Work and assume any
+ risks associated with Your exercise of permissions under this License.
+
+ 8. Limitation of Liability. In no event and under no legal theory,
+ whether in tort (including negligence), contract, or otherwise,
+ unless required by applicable law (such as deliberate and grossly
+ negligent acts) or agreed to in writing, shall any Contributor be
+ liable to You for damages, including any direct, indirect, special,
+ incidental, or consequential damages of any character arising as a
+ result of this License or out of the use or inability to use the
+ Work (including but not limited to damages for loss of goodwill,
+ work stoppage, computer failure or malfunction, or any and all
+ other commercial damages or losses), even if such Contributor
+ has been advised of the possibility of such damages.
+
+ 9. Accepting Warranty or Additional Liability. While redistributing
+ the Work or Derivative Works thereof, You may choose to offer,
+ and charge a fee for, acceptance of support, warranty, indemnity,
+ or other liability obligations and/or rights consistent with this
+ License. However, in accepting such obligations, You may act only
+ on Your own behalf and on Your sole responsibility, not on behalf
+ of any other Contributor, and only if You agree to indemnify,
+ defend, and hold each Contributor harmless for any liability
+ incurred by, or claims asserted against, such Contributor by reason
+ of your accepting any such warranty or additional liability.
+
+ END OF TERMS AND CONDITIONS
+
+ APPENDIX: How to apply the Apache License to your work.
+
+ To apply the Apache License to your work, attach the following
+ boilerplate notice, with the fields enclosed by brackets "[]"
+ replaced with your own identifying information. (Don't include
+ the brackets!) The text should be enclosed in the appropriate
+ comment syntax for the file format. We also recommend that a
+ file or class name and description of purpose be included on the
+ same "printed page" as the copyright notice for easier
+ identification within third-party archives.
+
+ Copyright 1999-2005 The Apache Software Foundation
+
+ 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.
diff --git
a/zookeeper-server/src/main/resources/lib/simpleclient_servlet-0.6.0_LICENSE.txt
b/zookeeper-server/src/main/resources/lib/simpleclient_servlet-0.6.0_LICENSE.txt
new file mode 100644
index 0000000..6279e52
--- /dev/null
+++
b/zookeeper-server/src/main/resources/lib/simpleclient_servlet-0.6.0_LICENSE.txt
@@ -0,0 +1,202 @@
+
+ Apache License
+ Version 2.0, January 2004
+ http://www.apache.org/licenses/
+
+ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+ 1. Definitions.
+
+ "License" shall mean the terms and conditions for use, reproduction,
+ and distribution as defined by Sections 1 through 9 of this document.
+
+ "Licensor" shall mean the copyright owner or entity authorized by
+ the copyright owner that is granting the License.
+
+ "Legal Entity" shall mean the union of the acting entity and all
+ other entities that control, are controlled by, or are under common
+ control with that entity. For the purposes of this definition,
+ "control" means (i) the power, direct or indirect, to cause the
+ direction or management of such entity, whether by contract or
+ otherwise, or (ii) ownership of fifty percent (50%) or more of the
+ outstanding shares, or (iii) beneficial ownership of such entity.
+
+ "You" (or "Your") shall mean an individual or Legal Entity
+ exercising permissions granted by this License.
+
+ "Source" form shall mean the preferred form for making modifications,
+ including but not limited to software source code, documentation
+ source, and configuration files.
+
+ "Object" form shall mean any form resulting from mechanical
+ transformation or translation of a Source form, including but
+ not limited to compiled object code, generated documentation,
+ and conversions to other media types.
+
+ "Work" shall mean the work of authorship, whether in Source or
+ Object form, made available under the License, as indicated by a
+ copyright notice that is included in or attached to the work
+ (an example is provided in the Appendix below).
+
+ "Derivative Works" shall mean any work, whether in Source or Object
+ form, that is based on (or derived from) the Work and for which the
+ editorial revisions, annotations, elaborations, or other modifications
+ represent, as a whole, an original work of authorship. For the purposes
+ of this License, Derivative Works shall not include works that remain
+ separable from, or merely link (or bind by name) to the interfaces of,
+ the Work and Derivative Works thereof.
+
+ "Contribution" shall mean any work of authorship, including
+ the original version of the Work and any modifications or additions
+ to that Work or Derivative Works thereof, that is intentionally
+ submitted to Licensor for inclusion in the Work by the copyright owner
+ or by an individual or Legal Entity authorized to submit on behalf of
+ the copyright owner. For the purposes of this definition, "submitted"
+ means any form of electronic, verbal, or written communication sent
+ to the Licensor or its representatives, including but not limited to
+ communication on electronic mailing lists, source code control systems,
+ and issue tracking systems that are managed by, or on behalf of, the
+ Licensor for the purpose of discussing and improving the Work, but
+ excluding communication that is conspicuously marked or otherwise
+ designated in writing by the copyright owner as "Not a Contribution."
+
+ "Contributor" shall mean Licensor and any individual or Legal Entity
+ on behalf of whom a Contribution has been received by Licensor and
+ subsequently incorporated within the Work.
+
+ 2. Grant of Copyright License. Subject to the terms and conditions of
+ this License, each Contributor hereby grants to You a perpetual,
+ worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+ copyright license to reproduce, prepare Derivative Works of,
+ publicly display, publicly perform, sublicense, and distribute the
+ Work and such Derivative Works in Source or Object form.
+
+ 3. Grant of Patent License. Subject to the terms and conditions of
+ this License, each Contributor hereby grants to You a perpetual,
+ worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+ (except as stated in this section) patent license to make, have made,
+ use, offer to sell, sell, import, and otherwise transfer the Work,
+ where such license applies only to those patent claims licensable
+ by such Contributor that are necessarily infringed by their
+ Contribution(s) alone or by combination of their Contribution(s)
+ with the Work to which such Contribution(s) was submitted. If You
+ institute patent litigation against any entity (including a
+ cross-claim or counterclaim in a lawsuit) alleging that the Work
+ or a Contribution incorporated within the Work constitutes direct
+ or contributory patent infringement, then any patent licenses
+ granted to You under this License for that Work shall terminate
+ as of the date such litigation is filed.
+
+ 4. Redistribution. You may reproduce and distribute copies of the
+ Work or Derivative Works thereof in any medium, with or without
+ modifications, and in Source or Object form, provided that You
+ meet the following conditions:
+
+ (a) You must give any other recipients of the Work or
+ Derivative Works a copy of this License; and
+
+ (b) You must cause any modified files to carry prominent notices
+ stating that You changed the files; and
+
+ (c) You must retain, in the Source form of any Derivative Works
+ that You distribute, all copyright, patent, trademark, and
+ attribution notices from the Source form of the Work,
+ excluding those notices that do not pertain to any part of
+ the Derivative Works; and
+
+ (d) If the Work includes a "NOTICE" text file as part of its
+ distribution, then any Derivative Works that You distribute must
+ include a readable copy of the attribution notices contained
+ within such NOTICE file, excluding those notices that do not
+ pertain to any part of the Derivative Works, in at least one
+ of the following places: within a NOTICE text file distributed
+ as part of the Derivative Works; within the Source form or
+ documentation, if provided along with the Derivative Works; or,
+ within a display generated by the Derivative Works, if and
+ wherever such third-party notices normally appear. The contents
+ of the NOTICE file are for informational purposes only and
+ do not modify the License. You may add Your own attribution
+ notices within Derivative Works that You distribute, alongside
+ or as an addendum to the NOTICE text from the Work, provided
+ that such additional attribution notices cannot be construed
+ as modifying the License.
+
+ You may add Your own copyright statement to Your modifications and
+ may provide additional or different license terms and conditions
+ for use, reproduction, or distribution of Your modifications, or
+ for any such Derivative Works as a whole, provided Your use,
+ reproduction, and distribution of the Work otherwise complies with
+ the conditions stated in this License.
+
+ 5. Submission of Contributions. Unless You explicitly state otherwise,
+ any Contribution intentionally submitted for inclusion in the Work
+ by You to the Licensor shall be under the terms and conditions of
+ this License, without any additional terms or conditions.
+ Notwithstanding the above, nothing herein shall supersede or modify
+ the terms of any separate license agreement you may have executed
+ with Licensor regarding such Contributions.
+
+ 6. Trademarks. This License does not grant permission to use the trade
+ names, trademarks, service marks, or product names of the Licensor,
+ except as required for reasonable and customary use in describing the
+ origin of the Work and reproducing the content of the NOTICE file.
+
+ 7. Disclaimer of Warranty. Unless required by applicable law or
+ agreed to in writing, Licensor provides the Work (and each
+ Contributor provides its Contributions) on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+ implied, including, without limitation, any warranties or conditions
+ of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+ PARTICULAR PURPOSE. You are solely responsible for determining the
+ appropriateness of using or redistributing the Work and assume any
+ risks associated with Your exercise of permissions under this License.
+
+ 8. Limitation of Liability. In no event and under no legal theory,
+ whether in tort (including negligence), contract, or otherwise,
+ unless required by applicable law (such as deliberate and grossly
+ negligent acts) or agreed to in writing, shall any Contributor be
+ liable to You for damages, including any direct, indirect, special,
+ incidental, or consequential damages of any character arising as a
+ result of this License or out of the use or inability to use the
+ Work (including but not limited to damages for loss of goodwill,
+ work stoppage, computer failure or malfunction, or any and all
+ other commercial damages or losses), even if such Contributor
+ has been advised of the possibility of such damages.
+
+ 9. Accepting Warranty or Additional Liability. While redistributing
+ the Work or Derivative Works thereof, You may choose to offer,
+ and charge a fee for, acceptance of support, warranty, indemnity,
+ or other liability obligations and/or rights consistent with this
+ License. However, in accepting such obligations, You may act only
+ on Your own behalf and on Your sole responsibility, not on behalf
+ of any other Contributor, and only if You agree to indemnify,
+ defend, and hold each Contributor harmless for any liability
+ incurred by, or claims asserted against, such Contributor by reason
+ of your accepting any such warranty or additional liability.
+
+ END OF TERMS AND CONDITIONS
+
+ APPENDIX: How to apply the Apache License to your work.
+
+ To apply the Apache License to your work, attach the following
+ boilerplate notice, with the fields enclosed by brackets "[]"
+ replaced with your own identifying information. (Don't include
+ the brackets!) The text should be enclosed in the appropriate
+ comment syntax for the file format. We also recommend that a
+ file or class name and description of purpose be included on the
+ same "printed page" as the copyright notice for easier
+ identification within third-party archives.
+
+ Copyright 1999-2005 The Apache Software Foundation
+
+ 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.
