package com.fasterxml.clustermate.servlet;
import java.io.IOException;
import com.fasterxml.clustermate.api.ClusterMateConstants;
import com.fasterxml.clustermate.api.EntryKey;
import com.fasterxml.clustermate.api.NodeState;
import com.fasterxml.clustermate.service.store.StoredEntry;
import com.fasterxml.storemate.store.util.OperationDiagnostics;
/**
* Specialized sub-type of Entry servlet that will either serve request
* locally (if data available), or return redirect code to indicate
* client who to call instead.
*<p>
* TODO: complete -- not yet ready
*/
@SuppressWarnings("serial")
public class RoutingEntryServlet<K extends EntryKey, E extends StoredEntry<K>>
extends StoreEntryServlet<K,E>
{
public RoutingEntryServlet(StoreEntryServlet<K,E> base)
{
// true -> share metrics with the "real" servlet. Can separate in future if need be
super(base, true);
}
/*
/**********************************************************************
/* Overridable helper methods
/**********************************************************************
*/
protected int _findRetryCount(ServletServiceRequest request)
{
String str = request.getQueryParameter(ClusterMateConstants.QUERY_PARAM_RETRY_COUNT);
if (str != null) {
str = str.trim();
if (str.length() > 0) {
try {
return Integer.parseInt(str);
} catch (NumberFormatException e) { }
}
}
return -1;
}
/*
/**********************************************************************
/* Overridden handler methods
/**********************************************************************
*/
@Override
protected ServletServiceResponse _handleGet(ServletServiceRequest request, ServletServiceResponse response,
OperationDiagnostics stats, K key)
throws IOException
{
NodeState node = _findRedirect(request, response, key);
if (node == null) {
response = (ServletServiceResponse) _storeHandler.getEntry(request, response, key, stats);
_addStdHeaders(response);
return response;
}
// TODO: routing!
throw new IllegalStateException("Not yet implemented!");
}
@Override
protected ServletServiceResponse _handleHead(ServletServiceRequest request, ServletServiceResponse response,
OperationDiagnostics stats, K key)
throws IOException
{
NodeState node = _findRedirect(request, response, key);
if (node == null) {
_storeHandler.getEntryStats(request, response, key, stats);
_addStdHeaders(response);
return response;
}
// TODO: routing!
throw new IllegalStateException("Not yet implemented!");
}
@Override
protected ServletServiceResponse _handlePut(ServletServiceRequest request, ServletServiceResponse response,
OperationDiagnostics stats, K key)
throws IOException
{
NodeState node = _findRedirect(request, response, key);
if (node == null) {
_storeHandler.putEntry(request, response, key, request.getInputStream(),
stats);
_addStdHeaders(response);
return response;
}
throw new IllegalStateException("Not yet implemented!");
// TODO: routing!
}
@Override
protected ServletServiceResponse _handleDelete(ServletServiceRequest request, ServletServiceResponse response,
OperationDiagnostics stats, K key)
throws IOException
{
NodeState node = _findRedirect(request, response, key);
if (node == null) {
_storeHandler.removeEntry(request, response, key, stats);
_addStdHeaders(response);
return response;
}
throw new IllegalStateException("Not yet implemented!");
// TODO: routing!
}
/*
/**********************************************************************
/* Helper methods
/**********************************************************************
*/
protected NodeState _findRedirect(ServletServiceRequest request, ServletServiceResponse response,
K key)
{
// First: retry count always affects things
int retry = _findRetryCount(request);
// except for one case; first try, and we have entry locally
boolean hasLocally = _isStoredLocally(key);
if (hasLocally && (retry == 0)) {
return null;
}
// otherwise need to find ordered set of targets
// !!! TODO
return null;
}
protected boolean _isStoredLocally(K key) {
return _clusterView.containsLocally(key);
}
}