From d0777af76182ba9a0ba8bc483b9a9fd6bb281bd0 Mon Sep 17 00:00:00 2001
From: Puneet Oberai <poberai@netflix.com>
Date: Tue, 3 Sep 2013 15:38:59 -0700
Subject: [PATCH] Adding in eureka based host supplier - issue 394

---
 astyanax-contrib/conf/log4j.xml               |  13 +++
 .../eureka/EurekaBasedHostSupplier.java       | 103 ++++++++++++++++++
 build.gradle                                  |   9 ++
 settings.gradle                               |   2 +-
 4 files changed, 126 insertions(+), 1 deletion(-)
 create mode 100644 astyanax-contrib/conf/log4j.xml
 create mode 100644 astyanax-contrib/src/main/java/com/netflix/astyanax/contrib/eureka/EurekaBasedHostSupplier.java

diff --git a/astyanax-contrib/conf/log4j.xml b/astyanax-contrib/conf/log4j.xml
new file mode 100644
index 000000000..6d1e15624
--- /dev/null
+++ b/astyanax-contrib/conf/log4j.xml
@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd" >
+<log4j:configuration>
+  <appender name="stdout" class="org.apache.log4j.ConsoleAppender">
+    <layout class="org.apache.log4j.PatternLayout">
+      <param name="ConversionPattern" value="%d{ABSOLUTE} %5p %c{1}:%L - %m%n"/>
+    </layout>
+  </appender>
+  <root>
+    <priority value="info"></priority>
+    <appender-ref ref="stdout"/>
+  </root>
+</log4j:configuration>
diff --git a/astyanax-contrib/src/main/java/com/netflix/astyanax/contrib/eureka/EurekaBasedHostSupplier.java b/astyanax-contrib/src/main/java/com/netflix/astyanax/contrib/eureka/EurekaBasedHostSupplier.java
new file mode 100644
index 000000000..4c810bb4a
--- /dev/null
+++ b/astyanax-contrib/src/main/java/com/netflix/astyanax/contrib/eureka/EurekaBasedHostSupplier.java
@@ -0,0 +1,103 @@
+package com.netflix.astyanax.contrib.eureka;
+
+import java.util.List;
+
+import org.apache.commons.lang.StringUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.google.common.base.Function;
+import com.google.common.base.Predicate;
+import com.google.common.base.Supplier;
+import com.google.common.collect.Collections2;
+import com.google.common.collect.Lists;
+import com.netflix.appinfo.AmazonInfo;
+import com.netflix.appinfo.AmazonInfo.MetaDataKey;
+import com.netflix.appinfo.InstanceInfo;
+import com.netflix.appinfo.MyDataCenterInstanceConfig;
+import com.netflix.astyanax.connectionpool.Host;
+import com.netflix.discovery.DefaultEurekaClientConfig;
+import com.netflix.discovery.DiscoveryClient;
+import com.netflix.discovery.DiscoveryManager;
+import com.netflix.discovery.shared.Application;
+
+/**
+ * Simple class that implements {@link Supplier}<{@link List}<{@link Host}>>. It provides a List<{@link Host}>
+ * using the {@link DiscoveryManager} which is the eureka client. 
+ * 
+ * Note that the class needs the eureka application name to discover all instances for that application. 
+ * 
+ * @author poberai
+ */
+public class EurekaBasedHostSupplier implements Supplier<List<Host>> {
+
+    private static final Logger LOG = LoggerFactory.getLogger(EurekaBasedHostSupplier.class);
+
+    // The C* cluster name for discovering nodes
+    private final String applicationName;
+
+    public EurekaBasedHostSupplier(String applicationName) {
+        this.applicationName = applicationName.toUpperCase();
+        // initialize eureka client.  make sure eureka properties are properly configured in config.properties
+        DiscoveryManager.getInstance().initComponent(new MyDataCenterInstanceConfig(), new DefaultEurekaClientConfig());
+    }
+
+    @Override
+    public List<Host> get() {
+
+        DiscoveryClient discoveryClient = DiscoveryManager.getInstance().getDiscoveryClient();
+        if (discoveryClient == null) {
+            LOG.error("Error getting discovery client");
+            throw new RuntimeException("Failed to create discovery client");
+        }
+
+        Application app = discoveryClient.getApplication(applicationName);
+        List<Host> hosts = Lists.newArrayList();
+        
+        if (app == null) {
+            return hosts;
+        }
+        
+        List<InstanceInfo> ins = app.getInstances();
+        
+        if (ins == null || ins.isEmpty()) {
+            return hosts;
+        }
+        
+        hosts = Lists.newArrayList(Collections2.transform(
+                Collections2.filter(ins, new Predicate<InstanceInfo>() {
+                    @Override
+                    public boolean apply(InstanceInfo input) {
+                        return input.getStatus() == InstanceInfo.InstanceStatus.UP;
+                    }
+                }), new Function<InstanceInfo, Host>() {
+                    @Override
+                    public Host apply(InstanceInfo info) {
+                        String[] parts = StringUtils.split(
+                                StringUtils.split(info.getHostName(), ".")[0], '-');
+
+                        Host host = new Host(info.getHostName(), info.getPort())
+                        .addAlternateIpAddress(
+                                StringUtils.join(new String[] { parts[1], parts[2], parts[3],
+                                        parts[4] }, "."))
+                                        .addAlternateIpAddress(info.getIPAddr())
+                                        .setId(info.getId());
+
+                        try {
+                            if (info.getDataCenterInfo() instanceof AmazonInfo) {
+                                AmazonInfo amazonInfo = (AmazonInfo)info.getDataCenterInfo();
+                                host.setRack(amazonInfo.get(MetaDataKey.availabilityZone));
+                            }
+                        }
+                        catch (Throwable t) {
+                            LOG.error("Error getting rack for host " + host.getName(), t);
+                        }
+
+                        return host;
+                    }
+                }));
+
+
+        return hosts;
+    }
+}
diff --git a/build.gradle b/build.gradle
index 42f75a603..503666c79 100644
--- a/build.gradle
+++ b/build.gradle
@@ -56,6 +56,7 @@ project(':astyanax') {
         compile  project(':astyanax-recipes')
         compile  project(':astyanax-entity-mapper')
         compile  project(':astyanax-examples')
+        compile  project(':astyanax-contrib')
     }
 }
 
@@ -130,3 +131,11 @@ project(':astyanax-examples') {
         testCompile project(':astyanax-thrift')
     }
 }
+
+project(':astyanax-contrib') {
+    apply plugin: 'java'
+    dependencies {
+        compile  project(':astyanax-core')
+        compile 'com.netflix.eureka:eureka-client:1.1.110'
+    }
+}
diff --git a/settings.gradle b/settings.gradle
index 11c28240f..685030644 100644
--- a/settings.gradle
+++ b/settings.gradle
@@ -1,2 +1,2 @@
 rootProject.name='astyanax'
-include 'astyanax-core', 'astyanax-queue', 'astyanax-thrift', 'astyanax-recipes', 'astyanax-cassandra', 'astyanax-entity-mapper', 'astyanax-examples', 'astyanax'
+include 'astyanax-core', 'astyanax-queue', 'astyanax-thrift', 'astyanax-recipes', 'astyanax-cassandra', 'astyanax-entity-mapper', 'astyanax-examples', 'astyanax-contrib', 'astyanax'