package org.jgroups.protocols.relay.config;
import org.jgroups.JChannel;
import org.jgroups.stack.Protocol;
import org.w3c.dom.*;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import java.io.FileInputStream;
import java.io.InputStream;
import java.util.*;
/**
* Parses and maintains the RELAY2 configuration (in memory)
* @author Bela Ban
* @since 3.2
*/
public class RelayConfig {
protected static final String RELAY_CONFIG = "RelayConfiguration";
protected static final String SITES = "sites";
protected static final String SITE = "site";
protected static final String BRIDGES = "bridges";
protected static final String BRIDGE = "bridge";
protected static final String FORWARDS = "forwards";
protected static final String FORWARD = "forward";
/*public String toString() {
StringBuilder sb=new StringBuilder();
sb.append("sites:\n");
for(Map.Entry<String,SiteConfig> entry: sites.entrySet())
sb.append(entry.getKey() + " --> " + entry.getValue() + "\n");
return sb.toString();
}*/
/** Parses site names and their configuration (e.g. "nyc" --> SiteConfig) into the map passed as argument */
public static void parse(InputStream input, final Map<String,SiteConfig> map) throws Exception {
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
factory.setValidating(false); // for now
DocumentBuilder builder=factory.newDocumentBuilder();
Document document=builder.parse(input);
Element root=document.getDocumentElement();
match(RELAY_CONFIG, root.getNodeName(), true);
NodeList children=root.getChildNodes();
if(children == null || children.getLength() == 0)
return;
for(int i=0; i < children.getLength(); i++) {
Node node=children.item(i);
if(node.getNodeType() != Node.ELEMENT_NODE)
continue;
String element_name=node.getNodeName();
if(SITES.equals(element_name))
parseSites(map, node);
else
throw new Exception("expected <" + SITES + ">, but got " + "<" + element_name + ">");
}
}
protected static void parseSites(final Map<String,SiteConfig> map, Node root) throws Exception {
NodeList children=root.getChildNodes();
if(children == null || children.getLength() == 0)
return;
for(int i=0; i < children.getLength(); i++) {
Node node=children.item(i);
if(node.getNodeType() != Node.ELEMENT_NODE)
continue;
match(SITE, node.getNodeName(), true);
NamedNodeMap attrs=node.getAttributes();
if(attrs == null || attrs.getLength() == 0)
continue;
Attr name_attr=(Attr)attrs.getNamedItem("name");
Attr id_attr=(Attr)attrs.getNamedItem("id");
String name=name_attr.getValue();
short id=Short.parseShort(id_attr.getValue());
if(id < 0)
throw new Exception("Site ID must be >= 0");
if(map.containsKey(name))
throw new Exception("Site \"" + name + "\" already defined");
SiteConfig site_config=new SiteConfig(name, id);
map.put(name, site_config);
parseBridgesAndForwards(site_config, node);
}
// Verify that all sites have unique IDs
Set<Short> ids=new HashSet<Short>();
for(SiteConfig site_config: map.values()) {
if(ids.contains(site_config.getId()))
throw new Exception("Site ID \"" + site_config.getId() + "\" is defined multiple times (must be unique)");
ids.add(site_config.getId());
}
}
protected static void parseBridgesAndForwards(SiteConfig site_config, Node root) throws Exception {
NodeList children=root.getChildNodes();
if(children == null || children.getLength() == 0)
return;
for(int i=0; i < children.getLength(); i++) {
Node node=children.item(i);
if(node.getNodeType() != Node.ELEMENT_NODE)
continue;
String node_name=node.getNodeName();
if(BRIDGES.equals(node_name))
parseBridges(site_config, node);
else if(FORWARDS.equals(node_name))
parseForwards(site_config, node);
else
throw new Exception("expected \"" + BRIDGES + "\" or \"" + FORWARDS + "\" keywords");
}
}
protected static void parseBridges(SiteConfig site_config, Node root) throws Exception {
NodeList children=root.getChildNodes();
if(children == null || children.getLength() == 0)
return;
for(int i=0; i < children.getLength(); i++) {
Node node=children.item(i);
if(node.getNodeType() != Node.ELEMENT_NODE)
continue;
String node_name=node.getNodeName();
match(BRIDGE, node_name, true);
NamedNodeMap attrs=node.getAttributes();
if(attrs == null || attrs.getLength() == 0)
continue;
Attr name_attr=(Attr)attrs.getNamedItem("name");
Attr config_attr=(Attr)attrs.getNamedItem("config");
String name=name_attr != null? name_attr.getValue() : null;
String config=config_attr.getValue();
BridgeConfig bridge_config=new PropertiesBridgeConfig(name, config);
site_config.addBridge(bridge_config);
}
}
protected static void parseForwards(SiteConfig site_config, Node root) throws Exception {
NodeList children=root.getChildNodes();
if(children == null || children.getLength() == 0)
return;
for(int i=0; i < children.getLength(); i++) {
Node node=children.item(i);
if(node.getNodeType() != Node.ELEMENT_NODE)
continue;
String node_name=node.getNodeName();
match(FORWARD, node_name, true);
NamedNodeMap attrs=node.getAttributes();
if(attrs == null || attrs.getLength() == 0)
continue;
Attr to_attr=(Attr)attrs.getNamedItem("to");
Attr gw_attr=(Attr)attrs.getNamedItem("gateway");
String to=to_attr.getValue();
String gateway=gw_attr.getValue();
ForwardConfig forward_config=new ForwardConfig(to, gateway);
site_config.addForward(forward_config);
}
}
protected static void match(String expected_name, String name, boolean is_element) throws Exception {
if(!expected_name.equals(name))
throw new Exception((is_element? "Element " : "Attribute ") + "\"" + name + "\" didn't match \"" + expected_name + "\"");
}
public static class SiteConfig {
protected final String name;
protected final short id;
protected final List<BridgeConfig> bridges=new ArrayList<BridgeConfig>();
protected final List<ForwardConfig> forwards=new ArrayList<ForwardConfig>();
public SiteConfig(String name, short id) {
this.name=name;
this.id=id;
}
public short getId() {return id;}
public String getName() {return name;}
public List<BridgeConfig> getBridges() {return bridges;}
public List<ForwardConfig> getForwards() {return forwards;}
public SiteConfig addBridge(BridgeConfig bridge_config) {bridges.add(bridge_config); return this;}
public SiteConfig addForward(ForwardConfig forward_config) {forwards.add(forward_config); return this;}
public String toString() {
StringBuilder sb=new StringBuilder("name=" + name + " (id=" + id + ")\n");
if(!bridges.isEmpty())
for(BridgeConfig bridge_config: bridges)
sb.append(bridge_config).append("\n");
if(!forwards.isEmpty())
for(ForwardConfig forward_config: forwards)
sb.append(forward_config).append("\n");
return sb.toString();
}
}
public abstract static class BridgeConfig {
protected final String cluster_name;
protected BridgeConfig(String cluster_name) {this.cluster_name=cluster_name;}
public String getClusterName() {return cluster_name;}
public abstract JChannel createChannel() throws Exception;
public String toString() {return "cluster=" + cluster_name;}
}
public static class PropertiesBridgeConfig extends BridgeConfig {
protected final String config;
public PropertiesBridgeConfig(String cluster_name, String config) {
super(cluster_name);
this.config=config;
}
public JChannel createChannel() throws Exception {return new JChannel(config);}
public String toString() {return "config=" + config + super.toString();}
}
public static class ProgrammaticBridgeConfig extends BridgeConfig {
protected Protocol[] protocols;
public ProgrammaticBridgeConfig(String cluster_name, Protocol[] prots) {
super(cluster_name);
this.protocols=prots;
}
public JChannel createChannel() throws Exception {
return new JChannel(protocols);
}
public String toString() {
return super.toString() + ", protocols=" + printProtocols(protocols);
}
protected static String printProtocols(Protocol[] protocols) {
StringBuilder sb=new StringBuilder("[");
boolean first=true;
for(Protocol prot: protocols) {
if(first)
first=false;
else
sb.append(", ");
sb.append(prot.getName());
}
sb.append("]");
return sb.toString();
}
}
public static class ForwardConfig {
protected final String to;
protected final String gateway;
public ForwardConfig(String to, String gateway) {
this.to=to;
this.gateway=gateway;
}
public String getGateway() {return gateway;}
public String getTo() {return to;}
public String toString() {
return "forward to=" + to + " gateway=" + gateway;
}
}
public static void main(String[] args) throws Exception {
InputStream input=new FileInputStream("/home/bela/relay2.xml");
Map<String,SiteConfig> sites=new HashMap<String,SiteConfig>();
RelayConfig.parse(input, sites);
System.out.println("sites:");
for(Map.Entry<String,SiteConfig> entry: sites.entrySet())
System.out.println(entry.getKey() + ":\n" + entry.getValue() + "\n");
}
}