Ec2NameResolver minus commons httpclient

plugins/cloud/aws/src/main/java/org/elasticsearch/cloud/aws/network/Ec2NameResolver.java

@@ -1,15 +1,30 @@
+/*
+ * Licensed to Elastic Search and Shay Banon under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. Elastic Search 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.elasticsearch.cloud.aws.network;
 
+import java.io.BufferedReader;
 import java.io.IOException;
+import java.io.InputStreamReader;
 import java.net.InetAddress;
-import java.text.MessageFormat;
+import java.net.URL;
-import java.util.HashMap;
-import java.util.Map;
 
-import org.apache.commons.httpclient.HttpClient;
-import org.apache.commons.httpclient.HttpException;
-import org.apache.commons.httpclient.HttpStatus;
-import org.apache.commons.httpclient.methods.GetMethod;
 import org.elasticsearch.common.network.NetworkService.CustomNameResolver;
 
 /**
@@ -30,7 +45,11 @@ import org.elasticsearch.common.network.NetworkService.CustomNameResolver;
  */
 public class Ec2NameResolver implements CustomNameResolver {
 
-	// enum that can be added to over time with more meta-data types (such as ipv6 when this is available)
+	/**
+	 *  enum that can be added to over time with more meta-data types (such as ipv6 when this is available)
+	 *  
+	 * @author Paul_Loy
+	 */
 	private static enum Ec2HostnameType {
 
 		PRIVATE_IPv4("_ec2:privateIpv4_", "local-ipv4"),
@@ -38,6 +57,7 @@ public class Ec2NameResolver implements CustomNameResolver {
 		PUBLIC_IPv4 ("_ec2:publicIpv4_",  "public-ipv4"),
 		PUBLIC_DNS  ("_ec2:publicDns_",   "public-hostname"),
 
+		// some less verbose defaults
 		PUBLIC_IP   ("_ec2:publicIp_",    PUBLIC_IPv4.ec2Name),
 		PRIVATE_IP  ("_ec2:privateIp_",   PRIVATE_IPv4.ec2Name),
 		DEFAULT     ("_ec2",              PRIVATE_IPv4.ec2Name);
@@ -54,43 +74,54 @@ public class Ec2NameResolver implements CustomNameResolver {
 
 	private static final String EC2_METADATA_URL = "http://169.254.169.254/latest/meta-data/";
 
-	private final Ec2HostnameType type;
-
 	/**
 	 * Construct a {@link CustomNameResolver} with the given {@link Ec2HostnameType}
 	 * address type.
 	 * 
 	 * @param addressType the type of ec2 host to bind to.
 	 */
-	public Ec2NameResolver(Ec2HostnameType addressType) {
+	public Ec2NameResolver() {
-		this.type = addressType;
 	}
 
 	/**
 	 * @return the appropriate host resolved from ec2 meta-data.
 	 * @throws IOException if ec2 meta-data cannot be obtained.
 	 * 
-	 * @see CustomNameResolver#resolve()
+	 * @see CustomNameResolver#resolveIfPossible(String)
 	 */
-	@Override
+	public InetAddress resolve(Ec2HostnameType type) throws IOException {
-	public InetAddress resolve() throws IOException {
-		String ec2Url = EC2_METADATA_URL + this.type.ec2Name;
-		GetMethod ec2MetadataRequest = new GetMethod(ec2Url);
 		
-		int status = new HttpClient().executeMethod(ec2MetadataRequest);
+		URL url = new URL(EC2_METADATA_URL + type.ec2Name);
-		if (status != 200) {	
+		BufferedReader urlReader = new BufferedReader(new InputStreamReader(url.openStream()));
-			throw new HttpException(MessageFormat.format("unable to retrieve ec2 metadata from {0}. Response: {1} {2}", ec2Url, status, HttpStatus.getStatusText(status)));
+
+		String metadataResult = urlReader.readLine();
+		if (metadataResult == null || metadataResult.length() == 0) {
+			throw new IOException("no ec2 metadata returned from :" + url);
 		}
-		String metadataResult = ec2MetadataRequest.getResponseBodyAsString();
 		return InetAddress.getByName(metadataResult);
 	}
 
-	public static Map<String, CustomNameResolver> resolvers() {
+	/*
-		Map<String, CustomNameResolver> resolvers = new HashMap<String, CustomNameResolver>();
+	 * (non-Javadoc)
+	 * @see org.elasticsearch.common.network.NetworkService.CustomNameResolver#resolveDefault()
+	 */
+	@Override
+	public InetAddress resolveDefault() throws IOException {
+		return resolve(Ec2HostnameType.DEFAULT);
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.elasticsearch.common.network.NetworkService.CustomNameResolver#resolveIfPossible(java.lang.String)
+	 */
+	@Override
+	public InetAddress resolveIfPossible(String value) throws IOException {
 		for (Ec2HostnameType type : Ec2HostnameType.values()) {
-			resolvers.put(type.configName, new Ec2NameResolver(type));
+			if (type.configName.equals(value)) {
+				return resolve(type);
+			}
 		}
-		return resolvers;
+		return null;
 	}
 
 }