opendaylight/adsal/northbound/commons/src/main/java/org/opendaylight/controller/northbound/commons/NorthboundApplication.java

   1 /**
   2  * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8
   9 package org.opendaylight.controller.northbound.commons;
  10
  11 import java.util.Dictionary;
  12 import java.util.HashSet;
  13 import java.util.List;
  14 import java.util.Set;
  15
  16 import javax.ws.rs.core.Application;
  17 import javax.ws.rs.ext.ContextResolver;
  18 import javax.xml.bind.JAXBContext;
  19 import javax.xml.bind.JAXBException;
  20 import javax.xml.bind.annotation.XmlRootElement;
  21
  22 import org.opendaylight.controller.northbound.bundlescanner.IBundleScanService;
  23 import org.opendaylight.controller.northbound.commons.exception.GenericExceptionMapper;
  24 import org.opendaylight.controller.northbound.commons.query.QueryContextProvider;
  25 import org.osgi.framework.Bundle;
  26 import org.osgi.framework.BundleContext;
  27 import org.osgi.framework.BundleReference;
  28 import org.osgi.framework.FrameworkUtil;
  29 import org.osgi.framework.ServiceException;
  30 import org.osgi.framework.ServiceReference;
  31 import org.slf4j.Logger;
  32 import org.slf4j.LoggerFactory;
  33
  34 import com.fasterxml.jackson.databind.DeserializationFeature;
  35 import com.fasterxml.jackson.jaxrs.json.JacksonJaxbJsonProvider;
  36
  37 /**
  38  * Instance of javax.ws.rs.core.Application used to return the classes
  39  * that will be instantiated for JAXRS processing. This hooks onto the
  40  * bundle scanner service to provide JAXB classes to JAX-RS for prorcessing.
  41  */
  42 public class NorthboundApplication extends Application {
  43     public static final String JAXRS_RESOURCES_MANIFEST_NAME = "Jaxrs-Resources";
  44     public static final String JAXRS_EXCLUDES_MANIFEST_NAME = "Jaxrs-Exclude-Types";
  45     private static final Logger LOGGER = LoggerFactory.getLogger(NorthboundApplication.class);
  46     private final Set<Object> _singletons;
  47
  48     public NorthboundApplication() {
  49         _singletons = new HashSet<Object>();
  50         _singletons.add(new ContextResolver<JAXBContext>() {
  51             JAXBContext jaxbContext;
  52             @Override
  53             public synchronized JAXBContext getContext(Class<?> type) {
  54                 if (jaxbContext == null) {
  55                     jaxbContext = newJAXBContext();
  56                 }
  57                 return jaxbContext;
  58             }
  59
  60         } );
  61         _singletons.add(getJsonProvider());
  62         _singletons.add(new JacksonJsonProcessingExceptionMapper());
  63         _singletons.add(new QueryContextProvider());
  64         _singletons.add(new GenericExceptionMapper());
  65     }
  66
  67     ////////////////////////////////////////////////////////////////
  68     //  Application overrides
  69     ////////////////////////////////////////////////////////////////
  70
  71     @Override
  72     public Set<Object> getSingletons() {
  73         return _singletons;
  74     }
  75
  76     @Override
  77     public Set<Class<?>> getClasses() {
  78         Set<Class<?>> result = new HashSet<Class<?>>();
  79         result.addAll(findJAXRSResourceClasses());
  80         return result;
  81     }
  82
  83     private static final JacksonJaxbJsonProvider getJsonProvider() {
  84         JacksonJaxbJsonProvider jsonProvider = new JacksonJaxbJsonProvider();
  85         jsonProvider.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES,
  86                 false);
  87         return jsonProvider;
  88     }
  89
  90     private BundleContext getBundleContext() {
  91         ClassLoader tlcl = Thread.currentThread().getContextClassLoader();
  92         Bundle bundle = null;
  93
  94         if (tlcl instanceof BundleReference) {
  95             bundle = ((BundleReference) tlcl).getBundle();
  96         } else {
  97             LOGGER.warn("Unable to determine the bundle context based on " +
  98                         "thread context classloader.");
  99             bundle = FrameworkUtil.getBundle(this.getClass());
 100         }
 101         return (bundle == null ? null : bundle.getBundleContext());
 102     }
 103
 104     private static final IBundleScanService lookupBundleScanner(BundleContext ctx) {
 105         ServiceReference<?> svcRef = ctx.getServiceReference(IBundleScanService.class);
 106         if (svcRef == null) {
 107             throw new ServiceException("Unable to lookup IBundleScanService");
 108         }
 109         return IBundleScanService.class.cast(ctx.getService(svcRef));
 110     }
 111
 112     private final JAXBContext newJAXBContext() {
 113         BundleContext ctx = getBundleContext();
 114         IBundleScanService svc = lookupBundleScanner(ctx);
 115         try {
 116             List<Class<?>> cls = svc.getAnnotatedClasses(ctx,
 117                     new String[] { XmlRootElement.class.getPackage().getName() },
 118                     parseManifestEntry(ctx, JAXRS_EXCLUDES_MANIFEST_NAME),
 119                     true);
 120             return JAXBContext.newInstance(cls.toArray(new Class[cls.size()]));
 121         } catch (JAXBException je) {
 122             LOGGER.error("Error creating JAXBContext", je);
 123             return null;
 124         }
 125     }
 126
 127     private final Set<Class<?>> findJAXRSResourceClasses() {
 128         BundleContext ctx = getBundleContext();
 129         String bundleName = ctx.getBundle().getSymbolicName();
 130         Set<Class<?>> result = new HashSet<Class<?>>();
 131         ServiceException recordException = null;
 132         try {
 133             IBundleScanService svc = lookupBundleScanner(ctx);
 134             result.addAll(svc.getAnnotatedClasses(ctx,
 135                     new String[] { javax.ws.rs.Path.class.getName() },
 136                     null, false));
 137         } catch (ServiceException se) {
 138             recordException = se;
 139             LOGGER.debug("Error finding JAXRS resource annotated classes in " +
 140                     "bundle: {} error: {}.", bundleName, se.getMessage());
 141             // the bundle scan service cannot be lookedup. Lets attempt to
 142             // lookup the resources from the bundle manifest header
 143             for (String c : parseManifestEntry(ctx, JAXRS_RESOURCES_MANIFEST_NAME)) {
 144                 try {
 145                     result.add(ctx.getBundle().loadClass(c));
 146                 } catch (ClassNotFoundException cnfe) {
 147                     LOGGER.error("Cannot load class: {} in bundle: {} " +
 148                             "defined as MANIFEST JAX-RS resource", c, bundleName, cnfe);
 149                 }
 150             }
 151         }
 152
 153         if (result.size() == 0) {
 154             if (recordException != null) {
 155                 throw recordException;
 156             } else {
 157                 throw new ServiceException("No resource classes found in bundle:" +
 158                         ctx.getBundle().getSymbolicName());
 159             }
 160         }
 161         return result;
 162     }
 163
 164     private final Set<String> parseManifestEntry(BundleContext ctx, String name) {
 165         Set<String> result = new HashSet<String>();
 166         Dictionary<String,String> headers = ctx.getBundle().getHeaders();
 167         String header = headers.get(name);
 168         if (header != null) {
 169             for (String s : header.split(",")) {
 170                 s = s.trim();
 171                 if (s.length() > 0) {
 172                     result.add(s);
 173                 }
 174             }
 175         }
 176         return result;
 177     }
 178
 179 }