/**
* The custom {@link com.netflix.discovery.provider.Serializer} for serializing and deserializing
* the registry information from and to the eureka server.
*
* <p>The {@link com.netflix.discovery.provider.Serializer} used here is an <tt>Xstream</tt>
* serializer which uses the <tt>JSON</tt> format and custom fields.The XStream deserialization does
* not handle removal of fields and hence this custom mechanism. Since then {@link Auto} annotation
* introduced handles any fields that does not exist gracefully and is the recommended mechanism. If
* the user wishes to override the whole XStream serialization/deserialization mechanism with their
* own alternatives they can do so my implementing their own providers in {@link
* EntityBodyConverter}.
*
* @author Karthik Ranganathan, Greg Kim
*/
public final class Converters {
private static final String UNMARSHAL_ERROR = "UNMARSHAL_ERROR";
public static final String NODE_LEASE = "leaseInfo";
public static final String NODE_METADATA = "metadata";
public static final String NODE_DATACENTER = "dataCenterInfo";
public static final String NODE_INSTANCE = "instance";
public static final String NODE_APP = "application";
private static final Logger logger = LoggerFactory.getLogger(Converters.class);
private static final Counter UNMARSHALL_ERROR_COUNTER = Monitors.newCounter(UNMARSHAL_ERROR);
/** Serialize/deserialize {@link Applications} object types. */
public static class ApplicationsConverter implements Converter {
private static final String VERSIONS_DELTA = "versions_delta";
private static final String APPS_HASHCODE = "apps_hashcode";
/*
* (non-Javadoc)
*
* @see
* com.thoughtworks.xstream.converters.ConverterMatcher#canConvert(java
* .lang.Class)
*/
@Override
public boolean canConvert(@SuppressWarnings("rawtypes") Class clazz) {
return Applications.class == clazz;
}
/*
* (non-Javadoc)
*
* @see
* com.thoughtworks.xstream.converters.Converter#marshal(java.lang.Object
* , com.thoughtworks.xstream.io.HierarchicalStreamWriter,
* com.thoughtworks.xstream.converters.MarshallingContext)
*/
@Override
public void marshal(
Object source, HierarchicalStreamWriter writer, MarshallingContext context) {
Applications apps = (Applications) source;
writer.startNode(VERSIONS_DELTA);
writer.setValue(apps.getVersion().toString());
writer.endNode();
writer.startNode(APPS_HASHCODE);
writer.setValue(apps.getAppsHashCode());
writer.endNode();
for (Application app : apps.getRegisteredApplications()) {
writer.startNode(NODE_APP);
context.convertAnother(app);
writer.endNode();
}
}
/*
* (non-Javadoc)
*
* @see
* com.thoughtworks.xstream.converters.Converter#unmarshal(com.thoughtworks
* .xstream.io.HierarchicalStreamReader,
* com.thoughtworks.xstream.converters.UnmarshallingContext)
*/
@Override
public Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext context) {
Applications apps = new Applications();
while (reader.hasMoreChildren()) {
reader.moveDown();
String nodeName = reader.getNodeName();
if (NODE_APP.equals(nodeName)) {
apps.addApplication((Application) context.convertAnother(apps, Application.class));
} else if (VERSIONS_DELTA.equals(nodeName)) {
apps.setVersion(Long.valueOf(reader.getValue()));
} else if (APPS_HASHCODE.equals(nodeName)) {
apps.setAppsHashCode(reader.getValue());
}
reader.moveUp();
}
return apps;
}
}
/** Serialize/deserialize {@link Applications} object types. */
public static class ApplicationConverter implements Converter {
private static final String ELEM_NAME = "name";
/*
* (non-Javadoc)
*
* @see
* com.thoughtworks.xstream.converters.ConverterMatcher#canConvert(java
* .lang.Class)
*/
public boolean canConvert(@SuppressWarnings("rawtypes") Class clazz) {
return Application.class == clazz;
}
/*
* (non-Javadoc)
*
* @see
* com.thoughtworks.xstream.converters.Converter#marshal(java.lang.Object
* , com.thoughtworks.xstream.io.HierarchicalStreamWriter,
* com.thoughtworks.xstream.converters.MarshallingContext)
*/
@Override
public void marshal(
Object source, HierarchicalStreamWriter writer, MarshallingContext context) {
Application app = (Application) source;
writer.startNode(ELEM_NAME);
writer.setValue(app.getName());
writer.endNode();
for (InstanceInfo instanceInfo : app.getInstances()) {
writer.startNode(NODE_INSTANCE);
context.convertAnother(instanceInfo);
writer.endNode();
}
}
/*
* (non-Javadoc)
*
* @see
* com.thoughtworks.xstream.converters.Converter#unmarshal(com.thoughtworks
* .xstream.io.HierarchicalStreamReader,
* com.thoughtworks.xstream.converters.UnmarshallingContext)
*/
@Override
public Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext context) {
Application app = new Application();
while (reader.hasMoreChildren()) {
reader.moveDown();
String nodeName = reader.getNodeName();
if (ELEM_NAME.equals(nodeName)) {
app.setName(reader.getValue());
} else if (NODE_INSTANCE.equals(nodeName)) {
app.addInstance((InstanceInfo) context.convertAnother(app, InstanceInfo.class));
}
reader.moveUp();
}
return app;
}
}
/** Serialize/deserialize {@link InstanceInfo} object types. */
public static class InstanceInfoConverter implements Converter {
private static final String ELEM_OVERRIDDEN_STATUS = "overriddenstatus";
private static final String ELEM_HOST = "hostName";
private static final String ELEM_INSTANCE_ID = "instanceId";
private static final String ELEM_APP = "app";
private static final String ELEM_IP = "ipAddr";
private static final String ELEM_SID = "sid";
private static final String ELEM_STATUS = "status";
private static final String ELEM_PORT = "port";
private static final String ELEM_SECURE_PORT = "securePort";
private static final String ELEM_COUNTRY_ID = "countryId";
private static final String ELEM_IDENTIFYING_ATTR = "identifyingAttribute";
private static final String ATTR_ENABLED = "enabled";
/*
* (non-Javadoc)
*
* @see
* com.thoughtworks.xstream.converters.ConverterMatcher#canConvert(java
* .lang.Class)
*/
@Override
public boolean canConvert(@SuppressWarnings("rawtypes") Class clazz) {
return InstanceInfo.class == clazz;
}
/*
* (non-Javadoc)
*
* @see
* com.thoughtworks.xstream.converters.Converter#marshal(java.lang.Object
* , com.thoughtworks.xstream.io.HierarchicalStreamWriter,
* com.thoughtworks.xstream.converters.MarshallingContext)
*/
@Override
public void marshal(
Object source, HierarchicalStreamWriter writer, MarshallingContext context) {
InstanceInfo info = (InstanceInfo) source;
if (info.getInstanceId() != null) {
writer.startNode(ELEM_INSTANCE_ID);
writer.setValue(info.getInstanceId());
writer.endNode();
}
writer.startNode(ELEM_HOST);
writer.setValue(info.getHostName());
writer.endNode();
writer.startNode(ELEM_APP);
writer.setValue(info.getAppName());
writer.endNode();
writer.startNode(ELEM_IP);
writer.setValue(info.getIPAddr());
writer.endNode();
if (!("unknown".equals(info.getSID()) || "na".equals(info.getSID()))) {
writer.startNode(ELEM_SID);
writer.setValue(info.getSID());
writer.endNode();
}
writer.startNode(ELEM_STATUS);
writer.setValue(getStatus(info));
writer.endNode();
writer.startNode(ELEM_OVERRIDDEN_STATUS);
writer.setValue(info.getOverriddenStatus().name());
writer.endNode();
writer.startNode(ELEM_PORT);
writer.addAttribute(ATTR_ENABLED, String.valueOf(info.isPortEnabled(PortType.UNSECURE)));
writer.setValue(String.valueOf(info.getPort()));
writer.endNode();
writer.startNode(ELEM_SECURE_PORT);
writer.addAttribute(ATTR_ENABLED, String.valueOf(info.isPortEnabled(PortType.SECURE)));
writer.setValue(String.valueOf(info.getSecurePort()));
writer.endNode();
writer.startNode(ELEM_COUNTRY_ID);
writer.setValue(String.valueOf(info.getCountryId()));
writer.endNode();
if (info.getDataCenterInfo() != null) {
writer.startNode(NODE_DATACENTER);
// This is needed for backward compat. for now.
if (info.getDataCenterInfo().getName() == Name.Amazon) {
writer.addAttribute("class", "com.netflix.appinfo.AmazonInfo");
} else {
writer.addAttribute("class", "com.netflix.appinfo.InstanceInfo$DefaultDataCenterInfo");
}
context.convertAnother(info.getDataCenterInfo());
writer.endNode();
}
if (info.getLeaseInfo() != null) {
writer.startNode(NODE_LEASE);
context.convertAnother(info.getLeaseInfo());
writer.endNode();
}
if (info.getMetadata() != null) {
writer.startNode(NODE_METADATA);
// for backward compat. for now
if (info.getMetadata().size() == 0) {
writer.addAttribute("class", "java.util.Collections$EmptyMap");
}
context.convertAnother(info.getMetadata());
writer.endNode();
}
autoMarshalEligible(source, writer);
}
public String getStatus(InstanceInfo info) {
return info.getStatus().name();
}
/*
* (non-Javadoc)
*
* @see
* com.thoughtworks.xstream.converters.Converter#unmarshal(com.thoughtworks
* .xstream.io.HierarchicalStreamReader,
* com.thoughtworks.xstream.converters.UnmarshallingContext)
*/
@Override
@SuppressWarnings("unchecked")
public Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext context) {
InstanceInfo.Builder builder = InstanceInfo.Builder.newBuilder();
while (reader.hasMoreChildren()) {
reader.moveDown();
String nodeName = reader.getNodeName();
if (ELEM_HOST.equals(nodeName)) {
builder.setHostName(reader.getValue());
} else if (ELEM_INSTANCE_ID.equals(nodeName)) {
builder.setInstanceId(reader.getValue());
} else if (ELEM_APP.equals(nodeName)) {
builder.setAppName(reader.getValue());
} else if (ELEM_IP.equals(nodeName)) {
builder.setIPAddr(reader.getValue());
} else if (ELEM_SID.equals(nodeName)) {
builder.setSID(reader.getValue());
} else if (ELEM_IDENTIFYING_ATTR.equals(nodeName)) {
// nothing;
} else if (ELEM_STATUS.equals(nodeName)) {
builder.setStatus(InstanceStatus.toEnum(reader.getValue()));
} else if (ELEM_OVERRIDDEN_STATUS.equals(nodeName)) {
builder.setOverriddenStatus(InstanceStatus.toEnum(reader.getValue()));
} else if (ELEM_PORT.equals(nodeName)) {
builder.setPort(Integer.valueOf(reader.getValue()).intValue());
// Defaults to true
builder.enablePort(PortType.UNSECURE, !"false".equals(reader.getAttribute(ATTR_ENABLED)));
} else if (ELEM_SECURE_PORT.equals(nodeName)) {
builder.setSecurePort(Integer.valueOf(reader.getValue()).intValue());
// Defaults to false
builder.enablePort(PortType.SECURE, "true".equals(reader.getAttribute(ATTR_ENABLED)));
} else if (ELEM_COUNTRY_ID.equals(nodeName)) {
builder.setCountryId(Integer.valueOf(reader.getValue()).intValue());
} else if (NODE_DATACENTER.equals(nodeName)) {
builder.setDataCenterInfo(
(DataCenterInfo) context.convertAnother(builder, DataCenterInfo.class));
} else if (NODE_LEASE.equals(nodeName)) {
builder.setLeaseInfo((LeaseInfo) context.convertAnother(builder, LeaseInfo.class));
} else if (NODE_METADATA.equals(nodeName)) {
builder.setMetadata((Map<String, String>) context.convertAnother(builder, Map.class));
} else {
autoUnmarshalEligible(reader, builder.getRawInstance());
}
reader.moveUp();
}
return builder.build();
}
}
/** Serialize/deserialize {@link DataCenterInfo} object types. */
public static class DataCenterInfoConverter implements Converter {
private static final String ELEM_NAME = "name";
/*
* (non-Javadoc)
*
* @see
* com.thoughtworks.xstream.converters.ConverterMatcher#canConvert(java
* .lang.Class)
*/
@Override
public boolean canConvert(@SuppressWarnings("rawtypes") Class clazz) {
return DataCenterInfo.class.isAssignableFrom(clazz);
}
/*
* (non-Javadoc)
*
* @see
* com.thoughtworks.xstream.converters.Converter#marshal(java.lang.Object
* , com.thoughtworks.xstream.io.HierarchicalStreamWriter,
* com.thoughtworks.xstream.converters.MarshallingContext)
*/
@Override
public void marshal(
Object source, HierarchicalStreamWriter writer, MarshallingContext context) {
DataCenterInfo info = (DataCenterInfo) source;
writer.startNode(ELEM_NAME);
// For backward compat. for now
writer.setValue(info.getName().name());
writer.endNode();
if (info.getName() == Name.Amazon) {
AmazonInfo aInfo = (AmazonInfo) info;
writer.startNode(NODE_METADATA);
// for backward compat. for now
if (aInfo.getMetadata().size() == 0) {
writer.addAttribute("class", "java.util.Collections$EmptyMap");
}
context.convertAnother(aInfo.getMetadata());
writer.endNode();
}
}
/*
* (non-Javadoc)
*
* @see
* com.thoughtworks.xstream.converters.Converter#unmarshal(com.thoughtworks
* .xstream.io.HierarchicalStreamReader,
* com.thoughtworks.xstream.converters.UnmarshallingContext)
*/
@Override
@SuppressWarnings("unchecked")
public Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext context) {
DataCenterInfo info = null;
while (reader.hasMoreChildren()) {
reader.moveDown();
if (ELEM_NAME.equals(reader.getNodeName())) {
final String dataCenterName = reader.getValue();
if (DataCenterInfo.Name.Amazon.name().equalsIgnoreCase(dataCenterName)) {
info = new AmazonInfo();
} else {
final DataCenterInfo.Name name = DataCenterInfo.Name.valueOf(dataCenterName);
info =
new DataCenterInfo() {
@Override
public Name getName() {
return name;
}
};
}
} else if (NODE_METADATA.equals(reader.getNodeName())) {
if (info.getName() == Name.Amazon) {
Map<String, String> metadataMap =
(Map<String, String>) context.convertAnother(info, Map.class);
Map<String, String> metadataMapInter = new HashMap<String, String>(metadataMap.size());
for (Map.Entry<String, String> entry : metadataMap.entrySet()) {
metadataMapInter.put(
StringCache.intern(entry.getKey()), StringCache.intern(entry.getValue()));
}
((AmazonInfo) info).setMetadata(metadataMapInter);
}
}
reader.moveUp();
}
return info;
}
}
/** Serialize/deserialize {@link LeaseInfo} object types. */
public static class LeaseInfoConverter implements Converter {
private static final String ELEM_RENEW_INT = "renewalIntervalInSecs";
private static final String ELEM_DURATION = "durationInSecs";
private static final String ELEM_REG_TIMESTAMP = "registrationTimestamp";
private static final String ELEM_LAST_RENEW_TIMETSTAMP = "lastRenewalTimestamp";
private static final String ELEM_EVICTION_TIMESTAMP = "evictionTimestamp";
private static final String ELEM_SERVICE_UP_TIMESTAMP = "serviceUpTimestamp";
/*
* (non-Javadoc)
*
* @see
* com.thoughtworks.xstream.converters.ConverterMatcher#canConvert(java
* .lang.Class)
*/
@Override
@SuppressWarnings("unchecked")
public boolean canConvert(Class clazz) {
return LeaseInfo.class == clazz;
}
/*
* (non-Javadoc)
*
* @see
* com.thoughtworks.xstream.converters.Converter#marshal(java.lang.Object
* , com.thoughtworks.xstream.io.HierarchicalStreamWriter,
* com.thoughtworks.xstream.converters.MarshallingContext)
*/
@Override
public void marshal(
Object source, HierarchicalStreamWriter writer, MarshallingContext context) {
LeaseInfo info = (LeaseInfo) source;
writer.startNode(ELEM_RENEW_INT);
writer.setValue(String.valueOf(info.getRenewalIntervalInSecs()));
writer.endNode();
writer.startNode(ELEM_DURATION);
writer.setValue(String.valueOf(info.getDurationInSecs()));
writer.endNode();
writer.startNode(ELEM_REG_TIMESTAMP);
writer.setValue(String.valueOf(info.getRegistrationTimestamp()));
writer.endNode();
writer.startNode(ELEM_LAST_RENEW_TIMETSTAMP);
writer.setValue(String.valueOf(info.getRenewalTimestamp()));
writer.endNode();
writer.startNode(ELEM_EVICTION_TIMESTAMP);
writer.setValue(String.valueOf(info.getEvictionTimestamp()));
writer.endNode();
writer.startNode(ELEM_SERVICE_UP_TIMESTAMP);
writer.setValue(String.valueOf(info.getServiceUpTimestamp()));
writer.endNode();
}
/*
* (non-Javadoc)
*
* @see
* com.thoughtworks.xstream.converters.Converter#unmarshal(com.thoughtworks
* .xstream.io.HierarchicalStreamReader,
* com.thoughtworks.xstream.converters.UnmarshallingContext)
*/
@Override
public Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext context) {
LeaseInfo.Builder builder = LeaseInfo.Builder.newBuilder();
while (reader.hasMoreChildren()) {
reader.moveDown();
String nodeName = reader.getNodeName();
String nodeValue = reader.getValue();
if (nodeValue == null) {
continue;
}
long longValue = 0;
try {
longValue = Long.valueOf(nodeValue).longValue();
} catch (NumberFormatException ne) {
continue;
}
if (ELEM_DURATION.equals(nodeName)) {
builder.setDurationInSecs((int) longValue);
} else if (ELEM_EVICTION_TIMESTAMP.equals(nodeName)) {
builder.setEvictionTimestamp(longValue);
} else if (ELEM_LAST_RENEW_TIMETSTAMP.equals(nodeName)) {
builder.setRenewalTimestamp(longValue);
} else if (ELEM_REG_TIMESTAMP.equals(nodeName)) {
builder.setRegistrationTimestamp(longValue);
} else if (ELEM_RENEW_INT.equals(nodeName)) {
builder.setRenewalIntervalInSecs((int) longValue);
} else if (ELEM_SERVICE_UP_TIMESTAMP.equals(nodeName)) {
builder.setServiceUpTimestamp(longValue);
}
reader.moveUp();
}
return builder.build();
}
}
/** Serialize/deserialize application metadata. */
public static class MetadataConverter implements Converter {
/*
* (non-Javadoc)
*
* @see
* com.thoughtworks.xstream.converters.ConverterMatcher#canConvert(java
* .lang.Class)
*/
@Override
public boolean canConvert(@SuppressWarnings("rawtypes") Class type) {
return Map.class.isAssignableFrom(type);
}
/*
* (non-Javadoc)
*
* @see
* com.thoughtworks.xstream.converters.Converter#marshal(java.lang.Object
* , com.thoughtworks.xstream.io.HierarchicalStreamWriter,
* com.thoughtworks.xstream.converters.MarshallingContext)
*/
@Override
@SuppressWarnings("unchecked")
public void marshal(
Object source, HierarchicalStreamWriter writer, MarshallingContext context) {
Map<String, String> map = (Map<String, String>) source;
for (Iterator<Entry<String, String>> iter = map.entrySet().iterator(); iter.hasNext(); ) {
Entry<String, String> entry = iter.next();
writer.startNode(entry.getKey());
writer.setValue(entry.getValue());
writer.endNode();
}
}
/*
* (non-Javadoc)
*
* @see
* com.thoughtworks.xstream.converters.Converter#unmarshal(com.thoughtworks
* .xstream.io.HierarchicalStreamReader,
* com.thoughtworks.xstream.converters.UnmarshallingContext)
*/
@Override
public Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext context) {
return unmarshalMap(reader, context);
}
private Map<String, String> unmarshalMap(
HierarchicalStreamReader reader, UnmarshallingContext context) {
Map<String, String> map = Collections.emptyMap();
while (reader.hasMoreChildren()) {
if (map == Collections.EMPTY_MAP) {
map = new HashMap<String, String>();
}
reader.moveDown();
String key = reader.getNodeName();
String value = reader.getValue();
reader.moveUp();
map.put(StringCache.intern(key), value);
}
return map;
}
}
/**
* Marshal all the objects containing an {@link Auto} annotation automatically.
*
* @param o - The object's fields that needs to be marshalled.
* @param writer - The writer for which to write the information to.
*/
private static void autoMarshalEligible(Object o, HierarchicalStreamWriter writer) {
try {
Class c = o.getClass();
Field[] fields = c.getDeclaredFields();
Annotation annotation = null;
for (Field f : fields) {
annotation = f.getAnnotation(Auto.class);
if (annotation != null) {
f.setAccessible(true);
if (f.get(o) != null) {
writer.startNode(f.getName());
writer.setValue(String.valueOf(f.get(o)));
writer.endNode();
}
}
}
} catch (Throwable th) {
logger.error("Error in marshalling the object", th);
}
}
/**
* Unmarshal all the elements to their field values if the fields have the {@link Auto} annotation
* defined.
*
* @param reader - The reader where the elements can be read.
* @param o - The object for which the value of fields need to be populated.
*/
private static void autoUnmarshalEligible(HierarchicalStreamReader reader, Object o) {
try {
String nodeName = reader.getNodeName();
Class c = o.getClass();
Field f = null;
try {
f = c.getDeclaredField(nodeName);
} catch (NoSuchFieldException e) {
UNMARSHALL_ERROR_COUNTER.increment();
}
if (f == null) {
return;
}
Annotation annotation = f.getAnnotation(Auto.class);
if (annotation == null) {
return;
}
f.setAccessible(true);
String value = reader.getValue();
Class returnClass = f.getType();
if (value != null) {
if (!String.class.equals(returnClass)) {
Method method = returnClass.getDeclaredMethod("valueOf", java.lang.String.class);
Object valueObject = method.invoke(returnClass, value);
f.set(o, valueObject);
} else {
f.set(o, value);
}
}
} catch (Throwable th) {
logger.error("Error in unmarshalling the object:", th);
}
}
}
