// This software is released into the Public Domain. See copying.txt for details.
package org.openstreetmap.osmosis.replication.v0_6;
import java.io.File;
import java.util.Map;
import org.openstreetmap.osmosis.core.OsmosisRuntimeException;
import org.openstreetmap.osmosis.core.container.v0_6.ChangeContainer;
import org.openstreetmap.osmosis.core.sort.v0_6.ChangeForStreamableApplierComparator;
import org.openstreetmap.osmosis.core.sort.v0_6.ChangeSorter;
import org.openstreetmap.osmosis.core.task.v0_6.ChangeSink;
import org.openstreetmap.osmosis.core.task.v0_6.RunnableChangeSource;
import org.openstreetmap.osmosis.replication.common.ReplicationState;
import org.openstreetmap.osmosis.xml.v0_6.XmlChangeReader;
/**
* Downloads a set of replication files from a HTTP server, and merges them into a
* single output stream. It tracks the intervals covered by the current files
* and stores the current timestamp between invocations forming the basis of a
* replication mechanism.
*
* @author Brett Henderson
*/
public class ReplicationDownloader extends BaseReplicationDownloader implements RunnableChangeSource {
private ChangeSorter changeSorter;
/**
* Creates a new instance.
*
* @param workingDirectory
* The directory containing configuration and tracking files.
*/
public ReplicationDownloader(File workingDirectory) {
super(workingDirectory);
// We will sort all contents prior to sending to the sink. This adds overhead that may not
// always be required, but provides consistent behaviour.
changeSorter = new ChangeSorter(new ChangeForStreamableApplierComparator());
}
/**
* {@inheritDoc}
*/
@Override
public void setChangeSink(ChangeSink changeSink) {
changeSorter.setChangeSink(changeSink);
}
/**
* {@inheritDoc}
*/
@Override
protected void processInitialize(Map<String, Object> metaData) {
changeSorter.initialize(metaData);
}
/**
* {@inheritDoc}
*/
@Override
protected void processInitializeState(ReplicationState initialState) {
// We don't allow automatic state file initialization for replication
// downloading. This is the most common task used by end users to
// retrieve replication information. It is very rare that a user would
// want to begin from the latest server state file. In most cases
// they'll want to begin processing from a known point in time.
throw new OsmosisRuntimeException("The local state.txt file doesn't exist."
+ " See http://wiki.openstreetmap.org/wiki/Osmosis/Detailed_Usage"
+ "#--read-replication-interval-init_.28--rrii.29"
+ " for more details on how to create the state.txt file.");
}
/**
* {@inheritDoc}
*/
@Override
protected void processChangeset(XmlChangeReader xmlReader, ReplicationState replicationState) {
final ChangeSink localChangeSink = changeSorter;
xmlReader.setChangeSink(new ChangeSink() {
private ChangeSink suppressedChangeSink = localChangeSink;
@Override
public void initialize(Map<String, Object> metaData) {
// Suppress the call.
}
@Override
public void process(ChangeContainer change) {
suppressedChangeSink.process(change);
}
@Override
public void complete() {
// Suppress the call.
}
@Override
public void release() {
// Suppress the call.
} });
xmlReader.run();
}
/**
* {@inheritDoc}
*/
@Override
protected void processComplete() {
changeSorter.complete();
}
/**
* {@inheritDoc}
*/
@Override
protected void processRelease() {
changeSorter.release();
}
}