LMS-1527 Added factory to try different urls for connecting to OpenBIS.

SVN: 15928

openbis/source/java/ch/systemsx/cisd/openbis/generic/shared/DefaultLimsServiceStubFactory.java

+/*
+ * Copyright 2010 ETH Zuerich, CISD
+ *
+ * Licensed 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 ch.systemsx.cisd.openbis.generic.shared;
+
+import ch.systemsx.cisd.common.spring.HttpInvokerUtils;
+import ch.systemsx.cisd.openbis.generic.shared.OpenBisServiceFactory.ILimsServiceStubFactory;
+
+/**
+ * @author Chandrasekhar Ramakrishnan
+ */
+public class DefaultLimsServiceStubFactory implements ILimsServiceStubFactory
+{
+    public static final int SERVER_TIMEOUT_MIN = 5;
+
+    public IETLLIMSService createServiceStub(String serverUrl)
+    {
+        return HttpInvokerUtils.createServiceStub(IETLLIMSService.class, serverUrl,
+                SERVER_TIMEOUT_MIN);
+    }
+
+}

openbis/source/java/ch/systemsx/cisd/openbis/generic/shared/OpenBisServiceFactory.java

+/*
+ * Copyright 2010 ETH Zuerich, CISD
+ *
+ * Licensed 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 ch.systemsx.cisd.openbis.generic.shared;
+
+/**
+ * A factory for creating proxies to the openBIS application server.
+ * <p>
+ * The OpenBisServiceFactory will create a proxy by trying several possible locations for the
+ * service.
+ * <p>
+ * After calling {@link #createService}, you can get the url createService used by calling the
+ * {@link #getUsedServerUrl} method.
+ * 
+ * @author Chandrasekhar Ramakrishnan
+ */
+public class OpenBisServiceFactory
+{
+    /**
+     * An interface that can create a {@link IETLLIMSService} proxy to a service located at a given
+     * a URL.
+     * 
+     * @author Chandrasekhar Ramakrishnan
+     */
+    public static interface ILimsServiceStubFactory
+    {
+        /**
+         * Create a proxy to the service located at the serverURL. Implementations should not alter
+         * the url, e.g., by appending something to it.
+         * 
+         * @param serverUrl The URL of of the IETLLIMSService service
+         * @return IETLLIMSService The service located at the serverUrl
+         */
+        public IETLLIMSService createServiceStub(String serverUrl);
+    }
+
+    private final String initialServerUrl;
+
+    private final ILimsServiceStubFactory stubFactory;
+
+    private String usedServerUrl;
+
+    /**
+     * Constructor for the OpenBisServiceFactory. The service factory works best when the serverUrl
+     * is simply the protocol://machine:port of the openBIS application server. It will
+     * automatically append likely locations of the openBIS service to the url.
+     * <p>
+     * Examples:
+     * <ul>
+     * <li>OpenBisServiceFactory("http://localhost:8888/", stubFactory)</li>
+     * <li>OpenBisServiceFactory("https://openbis.ethz.ch:8443/", stubFactory)</li>
+     * </ul>
+     * 
+     * @param serverUrl The Url where the openBIS server is assumed to be.
+     * @param stubFactory A factory that, given a url, returns an IETLLIMSService proxy to the url
+     */
+    public OpenBisServiceFactory(String serverUrl, ILimsServiceStubFactory stubFactory)
+    {
+        this.initialServerUrl = serverUrl;
+        this.stubFactory = stubFactory;
+        this.usedServerUrl = "";
+    }
+
+    /**
+     * Create a IETLLIMSService by trying several possible locations for the service until one that
+     * works is found. If the service cannot be found, a proxy to the constructor-provided serverUrl
+     * will be returned.
+     */
+    public IETLLIMSService createService()
+    {
+        IETLLIMSService service;
+        usedServerUrl = computeOpenbisOpenbisServerUrl(initialServerUrl);
+        // Try the url that ends in openbis/openbis
+        service = stubFactory.createServiceStub(usedServerUrl + "/rmi-etl");
+        if (canConnectToService(service))
+        {
+            return service;
+        }
+
+        // Try the url that ends in just one openbis
+        usedServerUrl = computeOpenbisServerUrl(initialServerUrl);
+        service = stubFactory.createServiceStub(usedServerUrl + "/rmi-etl");
+        if (canConnectToService(service))
+        {
+            return service;
+        }
+
+        // Try the url as provided
+        usedServerUrl = initialServerUrl;
+        service = stubFactory.createServiceStub(usedServerUrl + "/rmi-etl");
+        return service;
+    }
+
+    /**
+     * Return the serverUrl used by the createService method. The result of this method only makes
+     * sense after calling createService.
+     */
+    public String getUsedServerUrl()
+    {
+        return usedServerUrl;
+    }
+
+    private boolean canConnectToService(IETLLIMSService service)
+    {
+        try
+        {
+            service.getVersion();
+        } catch (Exception e)
+        {
+            return false;
+        }
+        return true;
+    }
+
+    private String computeOpenbisOpenbisServerUrl(String serverUrl)
+    {
+        if (serverUrl.endsWith("/openbis/openbis"))
+        {
+            return serverUrl;
+        }
+
+        if (serverUrl.endsWith("/openbis"))
+        {
+            return serverUrl + "/openbis";
+        }
+
+        String myServerUrl = serverUrl;
+        if (false == serverUrl.endsWith("/"))
+        {
+            myServerUrl = myServerUrl + "/";
+        }
+        return myServerUrl + "openbis/openbis";
+    }
+
+    private String computeOpenbisServerUrl(String serverUrl)
+    {
+        if (serverUrl.endsWith("/openbis/openbis"))
+        {
+            return serverUrl.substring(0, serverUrl.length() - "/openbis".length());
+        }
+
+        if (serverUrl.endsWith("/openbis"))
+        {
+            return serverUrl;
+        }
+
+        String myServerUrl = serverUrl;
+        if (false == serverUrl.endsWith("/"))
+        {
+            myServerUrl = myServerUrl + "/";
+        }
+        return myServerUrl + "openbis";
+    }
+}