Ejemplo n.º 1
0
  public void processRequest(Request request) {
    if (LOG.isDebugEnabled()) {
      LOG.debug("Processing request:: " + request);
    }
    // request.addRQRec(">final");
    long traceMask = ZooTrace.CLIENT_REQUEST_TRACE_MASK;
    if (request.type == OpCode.ping) {
      traceMask = ZooTrace.SERVER_PING_TRACE_MASK;
    }
    if (LOG.isTraceEnabled()) {
      ZooTrace.logRequest(LOG, traceMask, 'E', request, "");
    }
    ProcessTxnResult rc = null;
    synchronized (zks.outstandingChanges) {
      while (!zks.outstandingChanges.isEmpty()
          && zks.outstandingChanges.get(0).zxid <= request.zxid) {
        ChangeRecord cr = zks.outstandingChanges.remove(0);
        if (cr.zxid < request.zxid) {
          LOG.warn("Zxid outstanding " + cr.zxid + " is less than current " + request.zxid);
        }
        if (zks.outstandingChangesForPath.get(cr.path) == cr) {
          zks.outstandingChangesForPath.remove(cr.path);
        }
      }
      if (request.hdr != null) {
        TxnHeader hdr = request.hdr;
        Record txn = request.txn;

        rc = zks.processTxn(hdr, txn);
      }
      // do not add non quorum packets to the queue.
      if (Request.isQuorum(request.type)) {
        zks.getZKDatabase().addCommittedProposal(request);
      }
    }

    if (request.hdr != null && request.hdr.getType() == OpCode.closeSession) {
      ServerCnxnFactory scxn = zks.getServerCnxnFactory();
      // this might be possible since
      // we might just be playing diffs from the leader
      if (scxn != null && request.cnxn == null) {
        // calling this if we have the cnxn results in the client's
        // close session response being lost - we've already closed
        // the session/socket here before we can send the closeSession
        // in the switch block below
        scxn.closeSession(request.sessionId);
        return;
      }
    }

    if (request.cnxn == null) {
      return;
    }
    ServerCnxn cnxn = request.cnxn;

    String lastOp = "NA";
    zks.decInProcess();
    Code err = Code.OK;
    Record rsp = null;
    boolean closeSession = false;
    try {
      if (request.hdr != null && request.hdr.getType() == OpCode.error) {
        throw KeeperException.create(KeeperException.Code.get(((ErrorTxn) request.txn).getErr()));
      }

      KeeperException ke = request.getException();
      if (ke != null && request.type != OpCode.multi) {
        throw ke;
      }

      if (LOG.isDebugEnabled()) {
        LOG.debug("{}", request);
      }
      switch (request.type) {
        case OpCode.ping:
          {
            zks.serverStats().updateLatency(request.createTime);

            lastOp = "PING";
            cnxn.updateStatsForResponse(
                request.cxid, request.zxid, lastOp, request.createTime, System.currentTimeMillis());

            cnxn.sendResponse(
                new ReplyHeader(-2, zks.getZKDatabase().getDataTreeLastProcessedZxid(), 0),
                null,
                "response");
            return;
          }
        case OpCode.createSession:
          {
            zks.serverStats().updateLatency(request.createTime);

            lastOp = "SESS";
            cnxn.updateStatsForResponse(
                request.cxid, request.zxid, lastOp, request.createTime, System.currentTimeMillis());

            zks.finishSessionInit(request.cnxn, true);
            return;
          }
        case OpCode.multi:
          {
            lastOp = "MULT";
            rsp = new MultiResponse();

            for (ProcessTxnResult subTxnResult : rc.multiResult) {

              OpResult subResult;

              switch (subTxnResult.type) {
                case OpCode.check:
                  subResult = new CheckResult();
                  break;
                case OpCode.create:
                  subResult = new CreateResult(subTxnResult.path);
                  break;
                case OpCode.delete:
                  subResult = new DeleteResult();
                  break;
                case OpCode.setData:
                  subResult = new SetDataResult(subTxnResult.stat);
                  break;
                case OpCode.error:
                  subResult = new ErrorResult(subTxnResult.err);
                  break;
                default:
                  throw new IOException("Invalid type of op");
              }

              ((MultiResponse) rsp).add(subResult);
            }

            break;
          }
        case OpCode.create:
          {
            lastOp = "CREA";
            rsp = new CreateResponse(rc.path);
            err = Code.get(rc.err);
            break;
          }
        case OpCode.delete:
          {
            lastOp = "DELE";
            err = Code.get(rc.err);
            break;
          }
        case OpCode.setData:
          {
            lastOp = "SETD";
            rsp = new SetDataResponse(rc.stat);
            err = Code.get(rc.err);
            break;
          }
        case OpCode.setACL:
          {
            lastOp = "SETA";
            rsp = new SetACLResponse(rc.stat);
            err = Code.get(rc.err);
            break;
          }
        case OpCode.closeSession:
          {
            lastOp = "CLOS";
            closeSession = true;
            err = Code.get(rc.err);
            break;
          }
        case OpCode.sync:
          {
            lastOp = "SYNC";
            SyncRequest syncRequest = new SyncRequest();
            ByteBufferInputStream.byteBuffer2Record(request.request, syncRequest);
            rsp = new SyncResponse(syncRequest.getPath());
            break;
          }
        case OpCode.check:
          {
            lastOp = "CHEC";
            rsp = new SetDataResponse(rc.stat);
            err = Code.get(rc.err);
            break;
          }
        case OpCode.exists:
          {
            lastOp = "EXIS";
            // TODO we need to figure out the security requirement for this!
            ExistsRequest existsRequest = new ExistsRequest();
            ByteBufferInputStream.byteBuffer2Record(request.request, existsRequest);
            String path = existsRequest.getPath();
            if (path.indexOf('\0') != -1) {
              throw new KeeperException.BadArgumentsException();
            }
            Stat stat = zks.getZKDatabase().statNode(path, existsRequest.getWatch() ? cnxn : null);
            rsp = new ExistsResponse(stat);
            break;
          }
        case OpCode.getData:
          {
            lastOp = "GETD";
            GetDataRequest getDataRequest = new GetDataRequest();
            ByteBufferInputStream.byteBuffer2Record(request.request, getDataRequest);
            DataNode n = zks.getZKDatabase().getNode(getDataRequest.getPath());
            if (n == null) {
              throw new KeeperException.NoNodeException();
            }
            Long aclL;
            synchronized (n) {
              aclL = n.acl;
            }
            PrepRequestProcessor.checkACL(
                zks, zks.getZKDatabase().convertLong(aclL), ZooDefs.Perms.READ, request.authInfo);
            Stat stat = new Stat();
            byte b[] =
                zks.getZKDatabase()
                    .getData(
                        getDataRequest.getPath(), stat, getDataRequest.getWatch() ? cnxn : null);
            rsp = new GetDataResponse(b, stat);
            break;
          }
        case OpCode.setWatches:
          {
            lastOp = "SETW";
            SetWatches setWatches = new SetWatches();
            // XXX We really should NOT need this!!!!
            request.request.rewind();
            ByteBufferInputStream.byteBuffer2Record(request.request, setWatches);
            long relativeZxid = setWatches.getRelativeZxid();
            zks.getZKDatabase()
                .setWatches(
                    relativeZxid,
                    setWatches.getDataWatches(),
                    setWatches.getExistWatches(),
                    setWatches.getChildWatches(),
                    cnxn);
            break;
          }
        case OpCode.getACL:
          {
            lastOp = "GETA";
            GetACLRequest getACLRequest = new GetACLRequest();
            ByteBufferInputStream.byteBuffer2Record(request.request, getACLRequest);
            Stat stat = new Stat();
            List<ACL> acl = zks.getZKDatabase().getACL(getACLRequest.getPath(), stat);
            rsp = new GetACLResponse(acl, stat);
            break;
          }
        case OpCode.getChildren:
          {
            lastOp = "GETC";
            GetChildrenRequest getChildrenRequest = new GetChildrenRequest();
            ByteBufferInputStream.byteBuffer2Record(request.request, getChildrenRequest);
            DataNode n = zks.getZKDatabase().getNode(getChildrenRequest.getPath());
            if (n == null) {
              throw new KeeperException.NoNodeException();
            }
            Long aclG;
            synchronized (n) {
              aclG = n.acl;
            }
            PrepRequestProcessor.checkACL(
                zks, zks.getZKDatabase().convertLong(aclG), ZooDefs.Perms.READ, request.authInfo);
            List<String> children =
                zks.getZKDatabase()
                    .getChildren(
                        getChildrenRequest.getPath(),
                        null,
                        getChildrenRequest.getWatch() ? cnxn : null);
            rsp = new GetChildrenResponse(children);
            break;
          }
        case OpCode.getChildren2:
          {
            lastOp = "GETC";
            GetChildren2Request getChildren2Request = new GetChildren2Request();
            ByteBufferInputStream.byteBuffer2Record(request.request, getChildren2Request);
            Stat stat = new Stat();
            DataNode n = zks.getZKDatabase().getNode(getChildren2Request.getPath());
            if (n == null) {
              throw new KeeperException.NoNodeException();
            }
            Long aclG;
            synchronized (n) {
              aclG = n.acl;
            }
            PrepRequestProcessor.checkACL(
                zks, zks.getZKDatabase().convertLong(aclG), ZooDefs.Perms.READ, request.authInfo);
            List<String> children =
                zks.getZKDatabase()
                    .getChildren(
                        getChildren2Request.getPath(),
                        stat,
                        getChildren2Request.getWatch() ? cnxn : null);
            rsp = new GetChildren2Response(children, stat);
            break;
          }
      }
    } catch (SessionMovedException e) {
      // session moved is a connection level error, we need to tear
      // down the connection otw ZOOKEEPER-710 might happen
      // ie client on slow follower starts to renew session, fails
      // before this completes, then tries the fast follower (leader)
      // and is successful, however the initial renew is then
      // successfully fwd/processed by the leader and as a result
      // the client and leader disagree on where the client is most
      // recently attached (and therefore invalid SESSION MOVED generated)
      cnxn.sendCloseSession();
      return;
    } catch (KeeperException e) {
      err = e.code();
    } catch (Exception e) {
      // log at error level as we are returning a marshalling
      // error to the user
      LOG.error("Failed to process " + request, e);
      StringBuilder sb = new StringBuilder();
      ByteBuffer bb = request.request;
      bb.rewind();
      while (bb.hasRemaining()) {
        sb.append(Integer.toHexString(bb.get() & 0xff));
      }
      LOG.error("Dumping request buffer: 0x" + sb.toString());
      err = Code.MARSHALLINGERROR;
    }

    long lastZxid = zks.getZKDatabase().getDataTreeLastProcessedZxid();
    ReplyHeader hdr = new ReplyHeader(request.cxid, lastZxid, err.intValue());

    zks.serverStats().updateLatency(request.createTime);
    cnxn.updateStatsForResponse(
        request.cxid, lastZxid, lastOp, request.createTime, System.currentTimeMillis());

    try {
      cnxn.sendResponse(hdr, rsp, "response");
      if (closeSession) {
        cnxn.sendCloseSession();
      }
    } catch (IOException e) {
      LOG.error("FIXMSG", e);
    }
  }