Implemented a flow cache so we can still operate while if our switches lose connection by flushing and re-inserting flows when they reconnect
diff --git a/src/main/java/net/onrc/onos/ofcontroller/bgproute/FlowCache.java b/src/main/java/net/onrc/onos/ofcontroller/bgproute/FlowCache.java
new file mode 100644
index 0000000..d1cb578
--- /dev/null
+++ b/src/main/java/net/onrc/onos/ofcontroller/bgproute/FlowCache.java
@@ -0,0 +1,158 @@
+package net.onrc.onos.ofcontroller.bgproute;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import net.floodlightcontroller.core.IFloodlightProviderService;
+import net.floodlightcontroller.core.IOFSwitch;
+
+import org.openflow.protocol.OFFlowMod;
+import org.openflow.protocol.OFMessage;
+import org.openflow.protocol.OFPort;
+import org.openflow.util.HexString;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class FlowCache {
+ private static Logger log = LoggerFactory.getLogger(FlowCache.class);
+
+ private IFloodlightProviderService floodlightProvider;
+
+ private Map<Long, List<OFFlowMod>> flowCache;
+
+ private Comparator<OFFlowMod> cookieComparator = new Comparator<OFFlowMod>() {
+ @Override
+ public int compare(OFFlowMod fm1, OFFlowMod fm2) {
+ long difference = fm2.getCookie() - fm1.getCookie();
+
+ if (difference > 0) {
+ return 1;
+ }
+ else if (difference < 0) {
+ return -1;
+ }
+ else {
+ return 0;
+ }
+ }
+ };
+
+ public FlowCache(IFloodlightProviderService floodlightProvider) {
+ this.floodlightProvider = floodlightProvider;
+
+ flowCache = new HashMap<Long, List<OFFlowMod>>();
+ }
+
+ public synchronized void write(long dpid, OFFlowMod flowMod) {
+ List<OFFlowMod> flowModList = new ArrayList<OFFlowMod>(1);
+ flowModList.add(flowMod);
+ write(dpid, flowModList);
+ }
+
+ public synchronized void write(long dpid, List<OFFlowMod> flowMods) {
+ ensureCacheForSwitch(dpid);
+
+ List<OFFlowMod> clones = new ArrayList<OFFlowMod>(flowMods.size());
+
+ //Somehow the OFFlowMods we get passed in will change later on.
+ //No idea how this happens, but we can just clone to prevent problems
+ try {
+ for (OFFlowMod fm : flowMods) {
+ clones.add(fm.clone());
+ }
+ } catch (CloneNotSupportedException e) {
+ log.debug("Clone exception", e);
+ }
+
+ flowCache.get(dpid).addAll(clones);
+
+ IOFSwitch sw = floodlightProvider.getSwitches().get(dpid);
+
+ if (sw == null) {
+ log.debug("Switch not found when writing flow mods");
+ return;
+ }
+
+ List<OFMessage> msgList = new ArrayList<OFMessage>(clones.size());
+ msgList.addAll(clones);
+
+ try {
+ sw.write(msgList, null);
+ } catch (IOException e) {
+ log.error("Error writing to switch", e);
+ }
+
+
+ }
+
+ public synchronized void delete(long dpid, OFFlowMod flowMod) {
+ List<OFFlowMod> flowModList = new ArrayList<OFFlowMod>(1);
+ flowModList.add(flowMod);
+ delete(dpid, flowModList);
+ }
+
+ public synchronized void delete(long dpid, List<OFFlowMod> flowMods) {
+ ensureCacheForSwitch(dpid);
+
+ //Remove the flow mods from the cache first before we alter them
+ flowCache.get(dpid).removeAll(flowMods);
+
+ //Alter the original flow mods to make them delete flow mods
+ for (OFFlowMod fm : flowMods) {
+ fm.setCommand(OFFlowMod.OFPFC_DELETE_STRICT)
+ .setOutPort(OFPort.OFPP_NONE)
+ .setLengthU(OFFlowMod.MINIMUM_LENGTH);
+
+ fm.getActions().clear();
+ }
+
+ IOFSwitch sw = floodlightProvider.getSwitches().get(dpid);
+ if (sw == null) {
+ log.debug("Switch not found when writing flow mods");
+ return;
+ }
+
+ List<OFMessage> msgList = new ArrayList<OFMessage>(flowMods.size());
+ msgList.addAll(flowMods);
+
+ try {
+ sw.write(msgList, null);
+ } catch (IOException e) {
+ log.error("Error writing to switch", e);
+ }
+ }
+
+ //TODO can the Prontos handle being sent all flow mods in one message?
+ public synchronized void switchConnected(IOFSwitch sw) {
+ log.debug("Switch connected: {}", sw);
+
+ ensureCacheForSwitch(sw.getId());
+
+ List<OFFlowMod> flowMods = flowCache.get(sw.getId());
+
+ Collections.sort(flowMods, cookieComparator);
+
+ sw.clearAllFlowMods();
+
+ List<OFMessage> messages = new ArrayList<OFMessage>(flowMods.size());
+ messages.addAll(flowMods);
+
+ try {
+ sw.write(messages, null);
+ } catch (IOException e) {
+ log.error("Failure writing flow mods to switch {}",
+ HexString.toHexString(sw.getId()));
+ }
+ }
+
+ private void ensureCacheForSwitch(long dpid) {
+ if (!flowCache.containsKey(dpid)) {
+ flowCache.put(dpid, new ArrayList<OFFlowMod>());
+ }
+ }
+}