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/* * Copyright 2010 Proofpoint, Inc. * * 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 io.airlift.jmx; import com.fasterxml.jackson.core.JsonGenerator; import com.fasterxml.jackson.core.JsonParser; import com.fasterxml.jackson.core.JsonToken; import com.fasterxml.jackson.databind.DeserializationContext; import com.fasterxml.jackson.databind.JsonMappingException; import com.fasterxml.jackson.databind.JsonNode; import com.fasterxml.jackson.databind.JsonSerializer; import com.fasterxml.jackson.databind.SerializerProvider; import com.fasterxml.jackson.databind.deser.std.StdScalarDeserializer; import com.fasterxml.jackson.databind.node.ObjectNode; import com.fasterxml.jackson.databind.ser.std.StdSerializer; import com.fasterxml.jackson.databind.ser.std.ToStringSerializer; import com.google.common.annotations.Beta; import com.google.common.collect.ImmutableList; import com.google.common.collect.ImmutableMap; import com.google.inject.Binder; import com.google.inject.Module; import io.airlift.discovery.client.DiscoveryBinder; import sun.management.LazyCompositeData; import javax.management.MalformedObjectNameException; import javax.management.ObjectName; import javax.management.openmbean.CompositeData; import javax.management.openmbean.OpenType; import javax.management.openmbean.TabularData; import java.io.IOException; import java.lang.reflect.Type; import java.net.InetAddress; import java.util.List; import java.util.Map; import java.util.Set; import static io.airlift.jaxrs.JaxrsBinder.jaxrsBinder; import static io.airlift.json.JsonBinder.jsonBinder; @Beta public class JmxHttpModule implements Module { @Override public void configure(Binder binder) { binder.disableCircularProxies(); jaxrsBinder(binder).bind(MBeanResource.class); jsonBinder(binder).addSerializerBinding(InetAddress.class).toInstance(ToStringSerializer.instance); jsonBinder(binder).addSerializerBinding(ObjectName.class).toInstance(ToStringSerializer.instance); jsonBinder(binder).addSerializerBinding(OpenType.class).toInstance(ToStringSerializer.instance); jsonBinder(binder).addSerializerBinding(CompositeData.class).to(CompositeDataSerializer.class); jsonBinder(binder).addSerializerBinding(TabularData.class).to(TabularDataSerializer.class); jsonBinder(binder).addDeserializerBinding(ObjectName.class).to(ObjectNameDeserializer.class); // jackson has a bug in the serializer selection code so it does not know that subclasses of LazyCompositeData are also CompositeData jsonBinder(binder).addSerializerBinding(LazyCompositeData.class).to(CompositeDataSerializer.class); DiscoveryBinder.discoveryBinder(binder).bindHttpAnnouncement("jmx-http"); } static class ObjectNameDeserializer extends StdScalarDeserializer<ObjectName> { public ObjectNameDeserializer() { super(ObjectName.class); } @Override public ObjectName deserialize(JsonParser jsonParser, DeserializationContext context) throws IOException { JsonToken token = jsonParser.getCurrentToken(); if (token == JsonToken.VALUE_STRING) { try { return ObjectName.getInstance(jsonParser.getText()); } catch (MalformedObjectNameException e) { throw context.instantiationException(getValueClass(), e); } } throw context.mappingException(getValueClass()); } } public static class TabularDataSerializer extends StdSerializer<TabularData> { public TabularDataSerializer() { super(TabularData.class, true); } @Override public void serialize(TabularData data, JsonGenerator jsonGenerator, SerializerProvider provider) throws IOException { jsonGenerator.writeStartArray(); JsonSerializer<Object> mapSerializer = provider.findValueSerializer(Map.class, null); for (Map<String, Object> map : toList(data)) { if (!map.isEmpty()) { mapSerializer.serialize(map, jsonGenerator, provider); } } jsonGenerator.writeEndArray(); } @Override public JsonNode getSchema(SerializerProvider provider, Type typeHint) throws JsonMappingException { // List<Map<String, Object> ObjectNode o = createSchemaNode("array", true); o.put("items", createSchemaNode("object", true)); return o; } } public static class CompositeDataSerializer extends StdSerializer<CompositeData> { public CompositeDataSerializer() { super(CompositeData.class, true); } @Override public void serialize(CompositeData data, JsonGenerator jsonGenerator, SerializerProvider provider) throws IOException { Map<String, Object> map = toMap(data); if (!map.isEmpty()) { jsonGenerator.writeStartObject(); JsonSerializer<Object> cachedSerializer = null; Class<?> cachedType = null; for (Map.Entry<String, Object> entry : map.entrySet()) { String key = entry.getKey(); jsonGenerator.writeFieldName(key); Object value = entry.getValue(); // get the serializer, but cache to reduce lookups Class<?> valueType = value.getClass(); JsonSerializer<Object> serializer; if (valueType == cachedType) { serializer = cachedSerializer; } else { serializer = provider.findValueSerializer(valueType, null); cachedSerializer = serializer; cachedType = valueType; } try { serializer.serialize(value, jsonGenerator, provider); } catch (Exception e) { wrapAndThrow(provider, e, map, key); } } jsonGenerator.writeEndObject(); } else { jsonGenerator.writeString("dain42"); } } @Override public JsonNode getSchema(SerializerProvider provider, Type typeHint) { return createSchemaNode("object", true); } } private static Map<String, Object> toMap(CompositeData data) { ImmutableMap.Builder<String, Object> builder = ImmutableMap.builder(); // never trust JMX to do the right thing Set<String> keySet = data.getCompositeType().keySet(); if (keySet != null) { for (String key : keySet) { if (key != null) { Object value = data.get(key); if (value != null) { builder.put(key, value); } } } } return builder.build(); } @SuppressWarnings("unchecked") private static List<Map<String, Object>> toList(TabularData data) { ImmutableList.Builder<Map<String, Object>> builder = ImmutableList.builder(); // never trust JMX to do the right thing Set<List<?>> keySet = (Set<List<?>>) data.keySet(); if (keySet != null) { for (List<?> key : keySet) { if (key != null && !key.isEmpty()) { Object[] index = key.toArray(new Object[key.size()]); CompositeData value = data.get(index); if (value != null) { builder.add(toMap(value)); } } } } return builder.build(); } }