/**
* Copyright 2013-2014 David Rusek <dave dot rusek at gmail dot com>
*
* 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 org.robotninjas.barge.jaxrs;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.core.JsonToken;
import com.fasterxml.jackson.core.Version;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonDeserializer;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.deser.std.StdDeserializer;
import com.fasterxml.jackson.databind.module.SimpleModule;
import com.fasterxml.jackson.jaxrs.json.JacksonJaxbJsonProvider;
import com.google.common.collect.Lists;
import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.List;
import jersey.repackaged.com.google.common.collect.Iterables;
import org.robotninjas.barge.api.AppendEntries;
import org.robotninjas.barge.api.AppendEntriesResponse;
import org.robotninjas.barge.api.Entry;
import org.robotninjas.barge.api.RequestVote;
import org.robotninjas.barge.api.RequestVoteResponse;
/**
* Utility methods for configuring Jackson.
*/
public abstract class Jackson {
/**
* @return a new Object mapper with configured deserializer for barge' object model.
*/
public static ObjectMapper objectMapper() {
ObjectMapper mapper = new ObjectMapper();
SimpleModule raftMessagesModule = new SimpleModule("MyModule", new Version(0, 1, 0, null, "org.robotninjas", "barge"))
.addDeserializer(RequestVote.class, new RequestVoteDeserializer())
.addDeserializer(HttpClusterConfig.class, new HttpClusterConfigDeserializer())
.addDeserializer(HttpReplica.class, new HttpReplicaDeserializer())
.addDeserializer(RequestVoteResponse.class, new RequestVoteResponseDeserializer())
.addDeserializer(AppendEntries.class, new AppendEntriesDeserializer())
.addDeserializer(AppendEntriesResponse.class, new AppendEntriesResponseDeserializer());
mapper.registerModule(raftMessagesModule);
return mapper;
}
/**
* @return a suitable provider with configured deserialization objects.
*/
public static JacksonJaxbJsonProvider customJacksonProvider() {
JacksonJaxbJsonProvider provider = new JacksonJaxbJsonProvider();
provider.setMapper(objectMapper());
return provider;
}
private static class RequestVoteDeserializer extends StdDeserializer<RequestVote> {
protected RequestVoteDeserializer() {
super(RequestVote.class);
}
/**
* @see <a href="http://www.cowtowncoder.com/blog/archives/2009/01/entry_132.html">Jackson Documentation</a>
*/
@Override
public RequestVote deserialize(JsonParser jsonParser, DeserializationContext deserializationContext) throws IOException {
RequestVote.Builder builder = RequestVote.newBuilder();
while (jsonParser.nextToken() != JsonToken.END_OBJECT) {
String fieldName = jsonParser.getCurrentName();
jsonParser.nextToken();
switch (fieldName) {
case "term":
builder.setTerm(jsonParser.getLongValue());
break;
case "candidateId":
builder.setCandidateId(jsonParser.getText());
break;
case "lastLogIndex":
builder.setLastLogIndex(jsonParser.getLongValue());
break;
case "lastLogTerm":
builder.setLastLogTerm(jsonParser.getLongValue());
break;
}
}
return builder.build();
}
}
private static class RequestVoteResponseDeserializer extends StdDeserializer<RequestVoteResponse> {
public RequestVoteResponseDeserializer() {
super(RequestVoteResponse.class);
}
/**
* @see <a href="http://www.cowtowncoder.com/blog/archives/2009/01/entry_132.html">Jackson Documentation</a>
*/
@Override
public RequestVoteResponse deserialize(JsonParser jsonParser, DeserializationContext deserializationContext) throws IOException {
RequestVoteResponse.Builder builder = RequestVoteResponse.newBuilder();
while (jsonParser.nextToken() != JsonToken.END_OBJECT) {
String fieldName = jsonParser.getCurrentName();
jsonParser.nextToken();
if (fieldName.equals("term")) {
builder.setTerm(jsonParser.getLongValue());
} else if (fieldName.equals("voteGranted")) {
builder.setVoteGranted(jsonParser.getBooleanValue());
}
}
return builder.build();
}
}
private static class AppendEntriesDeserializer extends StdDeserializer<AppendEntries> {
public AppendEntriesDeserializer() {
super(AppendEntries.class);
}
@Override
public AppendEntries deserialize(JsonParser jsonParser, DeserializationContext deserializationContext) throws IOException {
AppendEntries.Builder builder = AppendEntries.newBuilder();
while (jsonParser.nextToken() != JsonToken.END_OBJECT) {
String fieldName = jsonParser.getCurrentName();
JsonToken token = jsonParser.nextToken();
switch (fieldName) {
case "term":
builder.setTerm(jsonParser.getLongValue());
break;
case "prevLogIndex":
builder.setPrevLogIndex(jsonParser.getLongValue());
break;
case "prevLogTerm":
builder.setPrevLogTerm(jsonParser.getLongValue());
break;
case "commitIndex":
builder.setCommitIndex(jsonParser.getLongValue());
break;
case "leaderId":
builder.setLeaderId(jsonParser.getText());
break;
case "entriesList":
if (token != JsonToken.START_ARRAY) {
throw new IOException("entriesList should be an array, got " + token);
}
while (jsonParser.nextToken() != JsonToken.END_ARRAY) {
builder.addEntry(deserializeEntry(jsonParser));
}
break;
}
}
return builder.build();
}
private Entry deserializeEntry(JsonParser jsonParser) throws IOException {
Entry.Builder builder = Entry.newBuilder();
while (jsonParser.nextToken() != JsonToken.END_OBJECT) {
String fieldName = jsonParser.getCurrentName();
jsonParser.nextToken();
if (fieldName.equals("term")) {
builder.setTerm(jsonParser.getLongValue());
} else if (fieldName.equals("command")) {
builder.setCommand(jsonParser.getBinaryValue());
}
}
return builder.build();
}
}
private static class AppendEntriesResponseDeserializer extends StdDeserializer<AppendEntriesResponse> {
protected AppendEntriesResponseDeserializer() {
super(AppendEntriesResponse.class);
}
@Override
public AppendEntriesResponse deserialize(JsonParser jsonParser, DeserializationContext deserializationContext) throws IOException {
AppendEntriesResponse.Builder builder = AppendEntriesResponse.newBuilder();
while (jsonParser.nextToken() != JsonToken.END_OBJECT) {
String fieldName = jsonParser.getCurrentName();
jsonParser.nextToken();
switch (fieldName) {
case "term":
builder.setTerm(jsonParser.getLongValue());
break;
case "success":
builder.setSuccess(jsonParser.getBooleanValue());
break;
case "lastLogIndex":
builder.setLastLogIndex(jsonParser.getLongValue());
break;
}
}
return builder.build();
}
}
private static class HttpClusterConfigDeserializer extends JsonDeserializer<HttpClusterConfig> {
@Override
public HttpClusterConfig deserialize(JsonParser jsonParser, DeserializationContext ctxt) throws IOException, JsonProcessingException {
List<HttpReplica> replicas = Lists.newArrayList();
while (jsonParser.nextToken() != JsonToken.END_OBJECT) {
String fieldName = jsonParser.getCurrentName();
JsonToken token = jsonParser.nextToken();
switch (fieldName) {
case "cluster":
if (token != JsonToken.START_ARRAY) {
throw new IOException("cluster should be an array, got " + token);
}
while (jsonParser.nextToken() != JsonToken.END_ARRAY) {
replicas.add(jsonParser.readValueAs(HttpReplica.class));
}
break;
}
}
return new HttpClusterConfig(replicas.get(0), Iterables.toArray(Iterables.skip(replicas, 1), HttpReplica.class));
}
}
private static class HttpReplicaDeserializer extends JsonDeserializer<HttpReplica> {
@Override
public HttpReplica deserialize(JsonParser jsonParser, DeserializationContext ctxt) throws IOException, JsonProcessingException {
URI uri = null;
while (jsonParser.nextToken() != JsonToken.END_OBJECT) {
String fieldName = jsonParser.getCurrentName();
jsonParser.nextToken();
switch (fieldName) {
case "uri":
String uriString = jsonParser.getValueAsString();
try {
uri = new URI(uriString);
} catch (URISyntaxException e) {
throw new IllegalStateException("failed to build proper URI from parsed uri field " + uriString);
}
break;
}
}
return new HttpReplica(uri);
}
}
}
