com.datatorrent.stram.util.WebServicesClient.java Source code

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/**
 * 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);
        }

    }
}