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 com.datatorrent.stram.util; import java.io.IOException; import java.security.Principal; import java.util.HashSet; import java.util.Set; import java.util.concurrent.Future; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.apache.http.auth.AuthSchemeProvider; import org.apache.http.auth.AuthScope; import org.apache.http.auth.Credentials; import org.apache.http.auth.UsernamePasswordCredentials; import org.apache.http.client.CredentialsProvider; import org.apache.http.client.config.AuthSchemes; import org.apache.http.config.Lookup; import org.apache.http.config.RegistryBuilder; import org.apache.http.impl.auth.BasicSchemeFactory; import org.apache.http.impl.auth.DigestSchemeFactory; import org.apache.http.impl.auth.KerberosSchemeFactory; import org.apache.http.impl.auth.SPNegoSchemeFactory; import org.apache.http.impl.client.BasicCookieStore; import org.apache.http.impl.client.BasicCredentialsProvider; import org.apache.http.impl.client.HttpClientBuilder; import org.apache.http.impl.conn.PoolingHttpClientConnectionManager; import com.sun.jersey.api.client.AsyncWebResource; import com.sun.jersey.api.client.Client; import com.sun.jersey.api.client.WebResource; import com.sun.jersey.api.client.async.ITypeListener; import com.sun.jersey.api.client.config.ClientConfig; import com.sun.jersey.api.client.config.DefaultClientConfig; import com.sun.jersey.api.client.filter.ClientFilter; import com.sun.jersey.client.apache4.ApacheHttpClient4Handler; import com.datatorrent.stram.security.AuthScheme; /** * <p>WebServicesClient class.</p> * * @since 0.3.2 */ public class WebServicesClient { private static final Logger LOG = LoggerFactory.getLogger(WebServicesClient.class); private static final PoolingHttpClientConnectionManager connectionManager; private static final CredentialsProvider credentialsProvider; private static final RegistryBuilder<AuthSchemeProvider> registryBuilder; private static Lookup<AuthSchemeProvider> authRegistry; private static final int DEFAULT_CONNECT_TIMEOUT = 10000; private static final int DEFAULT_READ_TIMEOUT = 10000; private final Client client; private final Set<ClientFilter> clientFilters = new HashSet<>(); private static final Credentials DEFAULT_TOKEN_CREDENTIALS = new Credentials() { @Override public Principal getUserPrincipal() { return null; } @Override public String getPassword() { return null; } }; static { connectionManager = new PoolingHttpClientConnectionManager(); connectionManager.setMaxTotal(200); connectionManager.setDefaultMaxPerRoute(5); registryBuilder = RegistryBuilder.<AuthSchemeProvider>create(); credentialsProvider = new BasicCredentialsProvider(); // By default add SPNEGO so that it works even if auth is not explictly configured like before, in future // move it to auth setup below setupHttpAuthScheme(AuthSchemes.SPNEGO, new SPNegoSchemeFactory(true), AuthScope.ANY, DEFAULT_TOKEN_CREDENTIALS); authRegistry = registryBuilder.build(); } public static void initAuth(ConfigProvider configuration) { // Setting up BASIC and DIGEST auth setupUserPassAuthScheme(AuthScheme.BASIC, AuthSchemes.BASIC, new BasicSchemeFactory(), configuration); setupUserPassAuthScheme(AuthScheme.DIGEST, AuthSchemes.DIGEST, new DigestSchemeFactory(), configuration); // Adding kerberos standard auth setupHttpAuthScheme(AuthSchemes.KERBEROS, new KerberosSchemeFactory(), AuthScope.ANY, DEFAULT_TOKEN_CREDENTIALS); authRegistry = registryBuilder.build(); } private static void setupUserPassAuthScheme(AuthScheme scheme, String httpScheme, AuthSchemeProvider provider, ConfigProvider configuration) { String username = configuration.getProperty(scheme, "username"); String password = configuration.getProperty(scheme, "password"); if ((username != null) && (password != null)) { LOG.info("Setting up scheme {}", scheme); AuthScope authScope = new AuthScope(AuthScope.ANY_HOST, AuthScope.ANY_PORT, AuthScope.ANY_REALM, httpScheme); Credentials credentials = new UsernamePasswordCredentials(username, password); setupHttpAuthScheme(httpScheme, provider, authScope, credentials); } else if ((username != null) || (password != null)) { LOG.warn("Not setting up scheme {}, missing credentials {}", scheme, (username == null) ? "username" : "password"); } } private static void setupHttpAuthScheme(String httpScheme, AuthSchemeProvider provider, AuthScope authScope, Credentials credentials) { registryBuilder.register(httpScheme, provider); credentialsProvider.setCredentials(authScope, credentials); } public WebServicesClient() { this(new DefaultClientConfig()); client.getProperties().put(ClientConfig.PROPERTY_FOLLOW_REDIRECTS, true); client.getProperties().put(ClientConfig.PROPERTY_CONNECT_TIMEOUT, DEFAULT_CONNECT_TIMEOUT); client.getProperties().put(ClientConfig.PROPERTY_READ_TIMEOUT, DEFAULT_READ_TIMEOUT); } public WebServicesClient(ClientConfig config) { if (SecurityUtils.isHadoopWebSecurityEnabled()) { HttpClientBuilder httpClientBuilder = HttpClientBuilder.create(); httpClientBuilder.setConnectionManager(connectionManager); httpClientBuilder.setDefaultCredentialsProvider(credentialsProvider); httpClientBuilder.setDefaultAuthSchemeRegistry(authRegistry); ApacheHttpClient4Handler httpClientHandler = new ApacheHttpClient4Handler(httpClientBuilder.build(), new BasicCookieStore(), false); client = new Client(httpClientHandler, config); } else { client = Client.create(config); } } public WebServicesClient(Client client) { this.client = client; } public Client getClient() { return client; } // A bug in jersey Client results in a ClassCastException when using the built-in method in Client to check if // the filter is already present. Hence using a wrapper method to keep track of added filters. public boolean isFilterPresent(ClientFilter clientFilter) { return clientFilters.contains(clientFilter); } public void addFilter(ClientFilter clientFilter) { client.addFilter(clientFilter); clientFilters.add(clientFilter); } public void clearFilters() { client.removeAllFilters(); clientFilters.clear(); } public <T> T process(String url, Class<T> clazz, WebServicesHandler<T> handler) throws IOException { WebResource wr = client.resource(url); return process(wr.getRequestBuilder(), clazz, handler); } public <T> Future<T> process(String url, final ITypeListener<T> listener, WebServicesAsyncHandler<T> handler) throws IOException { AsyncWebResource wr = client.asyncResource(url); return process(wr, listener, handler); } public <T> T process(final WebResource.Builder wr, final Class<T> clazz, final WebServicesHandler<T> handler) throws IOException { return SecureExecutor.execute(new SecureExecutor.WorkLoad<T>() { @Override public T run() { return handler.process(wr, clazz); } }); } public <T> Future<T> process(final AsyncWebResource wr, final ITypeListener<T> listener, final WebServicesAsyncHandler<T> handler) throws IOException { return SecureExecutor.execute(new SecureExecutor.WorkLoad<Future<T>>() { @Override public Future<T> run() { return handler.process(wr, listener); } }); } public interface ConfigProvider { String getProperty(AuthScheme scheme, String name); } /** * * @param <T> */ public abstract static class WebServicesHandler<T> { public abstract T process(WebResource.Builder webResource, Class<T> clazz); @Override public String toString() { return "WebServicesHandler{Abstract class Useful in Future}"; } } /** * * @param <T> */ public abstract static class WebServicesAsyncHandler<T> { public abstract Future<T> process(AsyncWebResource webResource, ITypeListener<T> listener); @Override public String toString() { return "WebServicesAsyncHandler{Abstract class Useful in Future}"; } } public static class GetWebServicesHandler<T> extends WebServicesHandler<T> { @Override public T process(WebResource.Builder webResource, Class<T> clazz) { return webResource.get(clazz); } } public static class GetWebServicesAsyncHandler<T> extends WebServicesAsyncHandler<T> { @Override public Future<T> process(AsyncWebResource webResource, ITypeListener<T> listener) { return webResource.get(listener); } } public static class DeleteWebServicesHandler<T> extends WebServicesHandler<T> { @Override public T process(WebResource.Builder webResource, Class<T> clazz) { return webResource.delete(clazz); } } public static class DeleteWebServicesAsyncHandler<T> extends WebServicesAsyncHandler<T> { @Override public Future<T> process(AsyncWebResource webResource, ITypeListener<T> listener) { return webResource.delete(listener); } } }