/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.solr.handler;
import java.io.IOException;
import java.lang.invoke.MethodHandles;
import java.nio.charset.Charset;
import java.util.List;
import org.apache.solr.client.solrj.SolrServerException;
import org.apache.solr.client.solrj.impl.CloudSolrClient;
import org.apache.solr.client.solrj.request.UpdateRequest;
import org.apache.solr.client.solrj.response.UpdateResponse;
import org.apache.solr.common.SolrException;
import org.apache.solr.common.SolrInputDocument;
import org.apache.solr.update.CdcrUpdateLog;
import org.apache.solr.update.UpdateLog;
import org.apache.solr.update.processor.CdcrUpdateProcessor;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import static org.apache.solr.common.params.CommonParams.VERSION_FIELD;
/**
* The replication logic. Given a {@link org.apache.solr.handler.CdcrReplicatorState}, it reads all the new entries
* in the update log and forward them to the target cluster. If an error occurs, the replication is stopped and
* will be tried again later.
*/
public class CdcrReplicator implements Runnable {
private final CdcrReplicatorState state;
private final int batchSize;
private static final Logger log = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
public CdcrReplicator(CdcrReplicatorState state, int batchSize) {
this.state = state;
this.batchSize = batchSize;
}
@Override
public void run() {
CdcrUpdateLog.CdcrLogReader logReader = state.getLogReader();
CdcrUpdateLog.CdcrLogReader subReader = null;
if (logReader == null) {
log.warn("Log reader for target {} is not initialised, it will be ignored.", state.getTargetCollection());
return;
}
try {
// create update request
UpdateRequest req = new UpdateRequest();
// Add the param to indicate the {@link CdcrUpdateProcessor} to keep the provided version number
req.setParam(CdcrUpdateProcessor.CDCR_UPDATE, "");
// Start the benchmark timer
state.getBenchmarkTimer().start();
long counter = 0;
subReader = logReader.getSubReader();
for (int i = 0; i < batchSize; i++) {
Object o = subReader.next();
if (o == null) break; // we have reached the end of the update logs, we should close the batch
if (isDelete(o)) {
/*
* Deletes are sent one at a time.
*/
// First send out current batch of SolrInputDocument, the non-deletes.
List<SolrInputDocument> docs = req.getDocuments();
if (docs != null && docs.size() > 0) {
subReader.resetToLastPosition(); // Push back the delete for now.
this.sendRequest(req); // Send the batch update request
logReader.forwardSeek(subReader); // Advance the main reader to just before the delete.
o = subReader.next(); // Read the delete again
counter += docs.size();
req.clear();
}
// Process Delete
this.processUpdate(o, req);
this.sendRequest(req);
logReader.forwardSeek(subReader);
counter++;
req.clear();
} else {
this.processUpdate(o, req);
}
}
//Send the final batch out.
List<SolrInputDocument> docs = req.getDocuments();
if ((docs != null && docs.size() > 0)) {
this.sendRequest(req);
counter += docs.size();
}
// we might have read a single commit operation and reached the end of the update logs
logReader.forwardSeek(subReader);
log.info("Forwarded {} updates to target {}", counter, state.getTargetCollection());
} catch (Exception e) {
// report error and update error stats
this.handleException(e);
} finally {
// stop the benchmark timer
state.getBenchmarkTimer().stop();
// ensure that the subreader is closed and the associated pointer is removed
if (subReader != null) subReader.close();
}
}
private void sendRequest(UpdateRequest req) throws IOException, SolrServerException, CdcrReplicatorException {
UpdateResponse rsp = req.process(state.getClient());
if (rsp.getStatus() != 0) {
throw new CdcrReplicatorException(req, rsp);
}
state.resetConsecutiveErrors();
}
private boolean isDelete(Object o) {
List entry = (List) o;
int operationAndFlags = (Integer) entry.get(0);
int oper = operationAndFlags & UpdateLog.OPERATION_MASK;
return oper == UpdateLog.DELETE_BY_QUERY || oper == UpdateLog.DELETE;
}
private void handleException(Exception e) {
if (e instanceof CdcrReplicatorException) {
UpdateRequest req = ((CdcrReplicatorException) e).req;
UpdateResponse rsp = ((CdcrReplicatorException) e).rsp;
log.warn("Failed to forward update request {} to target: {}. Got response {}", req, state.getTargetCollection(), rsp);
state.reportError(CdcrReplicatorState.ErrorType.BAD_REQUEST);
} else if (e instanceof CloudSolrClient.RouteException) {
log.warn("Failed to forward update request to target: " + state.getTargetCollection(), e);
state.reportError(CdcrReplicatorState.ErrorType.BAD_REQUEST);
} else {
log.warn("Failed to forward update request to target: " + state.getTargetCollection(), e);
state.reportError(CdcrReplicatorState.ErrorType.INTERNAL);
}
}
private UpdateRequest processUpdate(Object o, UpdateRequest req) {
// should currently be a List<Oper,Ver,Doc/Id>
List entry = (List) o;
int operationAndFlags = (Integer) entry.get(0);
int oper = operationAndFlags & UpdateLog.OPERATION_MASK;
long version = (Long) entry.get(1);
// record the operation in the benchmark timer
state.getBenchmarkTimer().incrementCounter(oper);
switch (oper) {
case UpdateLog.ADD: {
// the version is already attached to the document
SolrInputDocument sdoc = (SolrInputDocument) entry.get(entry.size() - 1);
req.add(sdoc);
return req;
}
case UpdateLog.DELETE: {
byte[] idBytes = (byte[]) entry.get(2);
req.deleteById(new String(idBytes, Charset.forName("UTF-8")));
req.setParam(VERSION_FIELD, Long.toString(version));
return req;
}
case UpdateLog.DELETE_BY_QUERY: {
String query = (String) entry.get(2);
req.deleteByQuery(query);
req.setParam(VERSION_FIELD, Long.toString(version));
return req;
}
case UpdateLog.COMMIT: {
return null;
}
default:
throw new SolrException(SolrException.ErrorCode.SERVER_ERROR, "Unknown Operation! " + oper);
}
}
/**
* Exception to catch update request issues with the target cluster.
*/
public static class CdcrReplicatorException extends Exception {
private final UpdateRequest req;
private final UpdateResponse rsp;
public CdcrReplicatorException(UpdateRequest req, UpdateResponse rsp) {
this.req = req;
this.rsp = rsp;
}
}
}