Java tutorial
/** * Copyright 2013, Big Switch Networks, Inc. * * Licensed 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 net.floodlightcontroller.core.web; import java.io.IOException; import java.lang.Thread.State; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.concurrent.TimeUnit; import org.projectfloodlight.openflow.protocol.OFControllerRole; import org.projectfloodlight.openflow.protocol.OFFactories; import org.projectfloodlight.openflow.protocol.OFNiciraControllerRole; import org.projectfloodlight.openflow.protocol.OFNiciraControllerRoleReply; import org.projectfloodlight.openflow.protocol.OFRoleReply; import org.projectfloodlight.openflow.protocol.OFVersion; import org.projectfloodlight.openflow.types.DatapathId; import org.projectfloodlight.openflow.types.U64; import org.restlet.resource.Post; import org.restlet.resource.ServerResource; import net.floodlightcontroller.core.IOFSwitch; import net.floodlightcontroller.core.internal.IOFSwitchService; import org.restlet.resource.Get; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.fasterxml.jackson.core.JsonParser; import com.fasterxml.jackson.core.JsonToken; import com.fasterxml.jackson.databind.MappingJsonFactory; import com.google.common.util.concurrent.ListenableFuture; public class SwitchRoleResource extends ServerResource { protected static Logger log = LoggerFactory.getLogger(SwitchRoleResource.class); private static final String STR_ROLE_PREFIX = "ROLE_"; /* enum OFControllerRole is ROLE_XXX, so trim the ROLE_ when printing */ private static final String STR_ROLE_MASTER = "MASTER"; /* these are all assumed uppercase within this class */ private static final String STR_ROLE_SLAVE = "SLAVE"; private static final String STR_ROLE_EQUAL = "EQUAL"; private static final String STR_ROLE_OTHER = "OTHER"; @Get("json") public Map<String, String> getRole() { IOFSwitchService switchService = (IOFSwitchService) getContext().getAttributes() .get(IOFSwitchService.class.getCanonicalName()); String switchId = (String) getRequestAttributes().get(CoreWebRoutable.STR_SWITCH_ID); HashMap<String, String> model = new HashMap<String, String>(); if (switchId.equalsIgnoreCase(CoreWebRoutable.STR_ALL)) { for (IOFSwitch sw : switchService.getAllSwitchMap().values()) { switchId = sw.getId().toString(); model.put(switchId, sw.getControllerRole().toString().replaceFirst(STR_ROLE_PREFIX, "")); } return model; } else { try { DatapathId dpid = DatapathId.of(switchId); IOFSwitch sw = switchService.getSwitch(dpid); if (sw == null) { model.put("ERROR", "Switch Manager could not locate switch DPID " + dpid.toString()); return model; } else { model.put(dpid.toString(), sw.getControllerRole().toString().replaceFirst(STR_ROLE_PREFIX, "")); return model; } } catch (Exception e) { model.put("ERROR", "Could not parse switch DPID " + switchId); return model; } } } /* for some reason @Post("json") isn't working here... */ @Post public Map<String, String> setRole(String json) { IOFSwitchService switchService = (IOFSwitchService) getContext().getAttributes() .get(IOFSwitchService.class.getCanonicalName()); Map<String, String> retValue = new HashMap<String, String>(); String switchId = (String) getRequestAttributes().get(CoreWebRoutable.STR_SWITCH_ID); MappingJsonFactory f = new MappingJsonFactory(); JsonParser jp = null; String role = null; try { try { jp = f.createParser(json); } catch (IOException e) { e.printStackTrace(); } jp.nextToken(); if (jp.getCurrentToken() != JsonToken.START_OBJECT) { throw new IOException("Expected START_OBJECT"); } while (jp.nextToken() != JsonToken.END_OBJECT) { if (jp.getCurrentToken() != JsonToken.FIELD_NAME) { throw new IOException("Expected FIELD_NAME"); } String n = jp.getCurrentName().toLowerCase(); jp.nextToken(); switch (n) { case CoreWebRoutable.STR_ROLE: role = jp.getText(); if (switchId.equalsIgnoreCase(CoreWebRoutable.STR_ALL)) { for (IOFSwitch sw : switchService.getAllSwitchMap().values()) { List<SetConcurrentRoleThread> activeThreads = new ArrayList<SetConcurrentRoleThread>( switchService.getAllSwitchMap().size()); List<SetConcurrentRoleThread> pendingRemovalThreads = new ArrayList<SetConcurrentRoleThread>(); SetConcurrentRoleThread t; t = new SetConcurrentRoleThread(sw, parseRole(role)); activeThreads.add(t); t.start(); // Join all the threads after the timeout. Set a hard timeout // of 12 seconds for the threads to finish. If the thread has not // finished the switch has not replied yet and therefore we won't // add the switch's stats to the reply. for (int iSleepCycles = 0; iSleepCycles < 12; iSleepCycles++) { for (SetConcurrentRoleThread curThread : activeThreads) { if (curThread.getState() == State.TERMINATED) { retValue.put(curThread.getSwitch().getId().toString(), (curThread.getRoleReply() == null ? "Error communicating with switch. Role not changed." : curThread.getRoleReply().getRole().toString() .replaceFirst(STR_ROLE_PREFIX, ""))); pendingRemovalThreads.add(curThread); } } // remove the threads that have completed the queries to the switches for (SetConcurrentRoleThread curThread : pendingRemovalThreads) { activeThreads.remove(curThread); } // clear the list so we don't try to double remove them pendingRemovalThreads.clear(); // if we are done finish early so we don't always get the worst case if (activeThreads.isEmpty()) { break; } // sleep for 1 s here try { Thread.sleep(1000); } catch (InterruptedException e) { log.error("Interrupted while waiting for role replies", e); retValue.put("ERROR", "Thread sleep interrupted while waiting for role replies."); } } } } else { /* Must be a specific switch DPID then. */ try { DatapathId dpid = DatapathId.of(switchId); IOFSwitch sw = switchService.getSwitch(dpid); if (sw == null) { retValue.put("ERROR", "Switch Manager could not locate switch DPID " + dpid.toString()); } else { OFRoleReply reply = setSwitchRole(sw, parseRole(role)); retValue.put(sw.getId().toString(), (reply == null ? "Error communicating with switch. Role not changed." : reply.getRole().toString().replaceFirst(STR_ROLE_PREFIX, ""))); } } catch (Exception e) { retValue.put("ERROR", "Could not parse switch DPID " + switchId); } } break; default: retValue.put("ERROR", "Unrecognized JSON key."); break; } } } catch (IOException e) { e.printStackTrace(); retValue.put("ERROR", "Caught IOException while parsing JSON POST request in role request."); } return retValue; } protected class SetConcurrentRoleThread extends Thread { private OFRoleReply switchReply; private OFControllerRole role; private IOFSwitch sw; public SetConcurrentRoleThread(IOFSwitch sw, OFControllerRole role) { this.sw = sw; this.switchReply = null; this.role = role; } public OFRoleReply getRoleReply() { return switchReply; } public IOFSwitch getSwitch() { return sw; } public OFControllerRole getRole() { return role; } @Override public void run() { switchReply = setSwitchRole(sw, role); } } private static OFRoleReply setSwitchRole(IOFSwitch sw, OFControllerRole role) { try { if (sw.getOFFactory().getVersion().compareTo(OFVersion.OF_12) < 0) { OFNiciraControllerRole nrole; switch (role) { case ROLE_EQUAL: nrole = OFNiciraControllerRole.ROLE_OTHER; log.warn("Assuming EQUAL as OTHER for Nicira role request."); break; case ROLE_MASTER: nrole = OFNiciraControllerRole.ROLE_MASTER; break; case ROLE_SLAVE: nrole = OFNiciraControllerRole.ROLE_SLAVE; break; case ROLE_NOCHANGE: log.error("Nicira extension does not support NOCHANGE role. Thus, we won't change the role."); return OFFactories.getFactory(OFVersion.OF_13).buildRoleReply().setRole(sw.getControllerRole()) .setGenerationId(U64.ZERO).build(); default: log.error("Impossible to have anything other than MASTER, OTHER, or SLAVE for Nicira role."); return OFFactories.getFactory(OFVersion.OF_13).buildRoleReply().setRole(sw.getControllerRole()) .setGenerationId(U64.ZERO).build(); } ListenableFuture<OFNiciraControllerRoleReply> future = sw .writeRequest(sw.getOFFactory().buildNiciraControllerRoleRequest().setRole(nrole).build()); OFNiciraControllerRoleReply nreply = future.get(10, TimeUnit.SECONDS); if (nreply != null) { /* Turn the OFControllerRoleReply into a OFNiciraControllerRoleReply */ switch (nreply.getRole()) { case ROLE_MASTER: return OFFactories.getFactory(OFVersion.OF_13).buildRoleReply() .setRole(OFControllerRole.ROLE_MASTER).setGenerationId(U64.ZERO).build(); case ROLE_OTHER: return OFFactories.getFactory(OFVersion.OF_13).buildRoleReply() .setRole(OFControllerRole.ROLE_EQUAL).setGenerationId(U64.ZERO).build(); case ROLE_SLAVE: return OFFactories.getFactory(OFVersion.OF_13).buildRoleReply() .setRole(OFControllerRole.ROLE_SLAVE).setGenerationId(U64.ZERO).build(); default: log.error( "Impossible to have anything other than MASTER, OTHER, or SLAVE for Nicira role: {}.", nreply.getRole().toString()); break; } } else { log.error("Did not receive Nicira role reply for switch {}.", sw.getId().toString()); } } else { ListenableFuture<OFRoleReply> future = sw.writeRequest( sw.getOFFactory().buildRoleRequest().setGenerationId(U64.ZERO).setRole(role).build()); return future.get(10, TimeUnit.SECONDS); } } catch (Exception e) { log.error("Failure setting switch {} role to {}.", sw.toString(), role.toString()); log.error(e.getMessage()); } return null; } private static OFControllerRole parseRole(String role) { if (role == null || role.isEmpty()) { return OFControllerRole.ROLE_NOCHANGE; } role = role.toUpperCase(); if (role.contains(STR_ROLE_MASTER)) { return OFControllerRole.ROLE_MASTER; } else if (role.contains(STR_ROLE_SLAVE)) { return OFControllerRole.ROLE_SLAVE; } else if (role.contains(STR_ROLE_EQUAL) || role.contains(STR_ROLE_OTHER)) { return OFControllerRole.ROLE_EQUAL; } else { return OFControllerRole.ROLE_NOCHANGE; } } }