Java tutorial
// 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.cloudstack.region; import java.io.IOException; import java.io.InputStream; import java.io.ObjectInputStream; import java.io.UnsupportedEncodingException; import java.net.URLEncoder; import java.util.ArrayList; import java.util.Collections; import java.util.Iterator; import java.util.List; import java.util.StringTokenizer; import javax.crypto.Mac; import javax.crypto.spec.SecretKeySpec; import org.apache.commons.codec.binary.Base64; import org.apache.commons.httpclient.HttpClient; import org.apache.commons.httpclient.HttpException; import org.apache.commons.httpclient.HttpMethod; import org.apache.commons.httpclient.NameValuePair; import org.apache.commons.httpclient.methods.GetMethod; import org.apache.log4j.Logger; import com.thoughtworks.xstream.XStream; import com.thoughtworks.xstream.io.xml.DomDriver; import com.cloud.domain.DomainVO; import com.cloud.user.UserAccount; import com.cloud.user.UserAccountVO; /** * Utility class for making API calls between peer Regions * */ public class RegionsApiUtil { public static final Logger s_logger = Logger.getLogger(RegionsApiUtil.class); /** * Makes an api call using region service end_point, api command and params * @param region * @param command * @param params * @return True, if api is successful */ protected static boolean makeAPICall(Region region, String command, List<NameValuePair> params) { try { String apiParams = buildParams(command, params); String url = buildUrl(apiParams, region); HttpClient client = new HttpClient(); HttpMethod method = new GetMethod(url); if (client.executeMethod(method) == 200) { return true; } else { return false; } } catch (HttpException e) { s_logger.error(e.getMessage()); return false; } catch (IOException e) { s_logger.error(e.getMessage()); return false; } } /** * Makes an api call using region service end_point, api command and params * Returns Account object on success * @param region * @param command * @param params * @return */ protected static RegionAccount makeAccountAPICall(Region region, String command, List<NameValuePair> params) { try { String url = buildUrl(buildParams(command, params), region); HttpClient client = new HttpClient(); HttpMethod method = new GetMethod(url); if (client.executeMethod(method) == 200) { InputStream is = method.getResponseBodyAsStream(); //Translate response to Account object XStream xstream = new XStream(new DomDriver()); xstream.alias("account", RegionAccount.class); xstream.alias("user", RegionUser.class); xstream.aliasField("id", RegionAccount.class, "uuid"); xstream.aliasField("name", RegionAccount.class, "accountName"); xstream.aliasField("accounttype", RegionAccount.class, "type"); xstream.aliasField("domainid", RegionAccount.class, "domainUuid"); xstream.aliasField("networkdomain", RegionAccount.class, "networkDomain"); xstream.aliasField("id", RegionUser.class, "uuid"); xstream.aliasField("accountId", RegionUser.class, "accountUuid"); try (ObjectInputStream in = xstream.createObjectInputStream(is);) { return (RegionAccount) in.readObject(); } catch (IOException e) { s_logger.error(e.getMessage()); return null; } } else { return null; } } catch (HttpException e) { s_logger.error(e.getMessage()); return null; } catch (IOException e) { s_logger.error(e.getMessage()); return null; } catch (ClassNotFoundException e) { s_logger.error(e.getMessage()); return null; } } /** * Makes an api call using region service end_point, api command and params * Returns Domain object on success * @param region * @param command * @param params * @return */ protected static RegionDomain makeDomainAPICall(Region region, String command, List<NameValuePair> params) { try { String url = buildUrl(buildParams(command, params), region); HttpClient client = new HttpClient(); HttpMethod method = new GetMethod(url); if (client.executeMethod(method) == 200) { InputStream is = method.getResponseBodyAsStream(); XStream xstream = new XStream(new DomDriver()); //Translate response to Domain object xstream.alias("domain", RegionDomain.class); xstream.aliasField("id", RegionDomain.class, "uuid"); xstream.aliasField("parentdomainid", RegionDomain.class, "parentUuid"); xstream.aliasField("networkdomain", DomainVO.class, "networkDomain"); try (ObjectInputStream in = xstream.createObjectInputStream(is);) { return (RegionDomain) in.readObject(); } catch (IOException e) { s_logger.error(e.getMessage()); return null; } } else { return null; } } catch (HttpException e) { s_logger.error(e.getMessage()); return null; } catch (IOException e) { s_logger.error(e.getMessage()); return null; } catch (ClassNotFoundException e) { s_logger.error(e.getMessage()); return null; } } /** * Makes an api call using region service end_point, api command and params * Returns UserAccount object on success * @param region * @param command * @param params * @return */ protected static UserAccount makeUserAccountAPICall(Region region, String command, List<NameValuePair> params) { try { String url = buildUrl(buildParams(command, params), region); HttpClient client = new HttpClient(); HttpMethod method = new GetMethod(url); if (client.executeMethod(method) == 200) { InputStream is = method.getResponseBodyAsStream(); XStream xstream = new XStream(new DomDriver()); xstream.alias("useraccount", UserAccountVO.class); xstream.aliasField("id", UserAccountVO.class, "uuid"); try (ObjectInputStream in = xstream.createObjectInputStream(is);) { return (UserAccountVO) in.readObject(); } catch (IOException e) { s_logger.error(e.getMessage()); return null; } } else { return null; } } catch (HttpException e) { s_logger.error(e.getMessage()); return null; } catch (IOException e) { s_logger.error(e.getMessage()); return null; } catch (ClassNotFoundException e) { s_logger.error(e.getMessage()); return null; } } /** * Builds parameters string with command and encoded param values * @param command * @param params * @return */ protected static String buildParams(String command, List<NameValuePair> params) { StringBuffer paramString = new StringBuffer("command=" + command); Iterator<NameValuePair> iter = params.iterator(); try { while (iter.hasNext()) { NameValuePair param = iter.next(); if (param.getValue() != null && !(param.getValue().isEmpty())) { paramString.append("&" + param.getName() + "=" + URLEncoder.encode(param.getValue(), "UTF-8")); } } } catch (UnsupportedEncodingException e) { s_logger.error(e.getMessage()); return null; } return paramString.toString(); } /** * Build URL for api call using region end_point * Parameters are sorted and signed using secret_key * @param apiParams * @param region * @return */ private static String buildUrl(String apiParams, Region region) { String apiKey = ""; String secretKey = ""; String encodedApiKey; try { encodedApiKey = URLEncoder.encode(apiKey, "UTF-8"); List<String> sortedParams = new ArrayList<String>(); sortedParams.add("apikey=" + encodedApiKey.toLowerCase()); StringTokenizer st = new StringTokenizer(apiParams, "&"); String url = null; boolean first = true; while (st.hasMoreTokens()) { String paramValue = st.nextToken(); String param = paramValue.substring(0, paramValue.indexOf("=")); String value = paramValue.substring(paramValue.indexOf("=") + 1, paramValue.length()); if (first) { url = param + "=" + value; first = false; } else { url = url + "&" + param + "=" + value; } sortedParams.add(param.toLowerCase() + "=" + value.toLowerCase()); } Collections.sort(sortedParams); //Construct the sorted URL and sign and URL encode the sorted URL with your secret key String sortedUrl = null; first = true; for (String param : sortedParams) { if (first) { sortedUrl = param; first = false; } else { sortedUrl = sortedUrl + "&" + param; } } String encodedSignature = signRequest(sortedUrl, secretKey); String finalUrl = region.getEndPoint() + "?" + apiParams + "&apiKey=" + apiKey + "&signature=" + encodedSignature; return finalUrl; } catch (UnsupportedEncodingException e) { s_logger.error(e.getMessage()); return null; } } /** * 1. Signs a string with a secret key using SHA-1 2. Base64 encode the result 3. URL encode the final result * * @param request * @param key * @return */ private static String signRequest(String request, String key) { try { Mac mac = Mac.getInstance("HmacSHA1"); SecretKeySpec keySpec = new SecretKeySpec(key.getBytes(), "HmacSHA1"); mac.init(keySpec); mac.update(request.getBytes()); byte[] encryptedBytes = mac.doFinal(); return URLEncoder.encode(Base64.encodeBase64String(encryptedBytes), "UTF-8"); } catch (Exception ex) { s_logger.error(ex.getMessage()); return null; } } }