HostController.java

package com.liveramp.hank.ui.controllers;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

import com.liveramp.hank.coordinator.Coordinator;
import com.liveramp.hank.coordinator.Host;
import com.liveramp.hank.coordinator.HostCommand;
import com.liveramp.hank.coordinator.HostDomain;
import com.liveramp.hank.coordinator.HostDomainPartition;
import com.liveramp.hank.coordinator.Hosts;
import com.liveramp.hank.coordinator.PartitionServerAddress;
import com.liveramp.hank.coordinator.Ring;
import com.liveramp.hank.coordinator.RingGroup;
import com.liveramp.hank.ui.URLEnc;

public class HostController extends Controller {
  private final Coordinator coordinator;

  public HostController(String name, Coordinator coordinator) {
    super(name);
    this.coordinator = coordinator;
    actions.put("enqueue_command", new Action() {
      @Override
      protected void action(HttpServletRequest req, HttpServletResponse resp) throws IOException {
        doEnqueueCommand(req, resp);
      }
    });
    actions.put("delete_partition", new Action() {
      @Override
      protected void action(HttpServletRequest req, HttpServletResponse resp) throws IOException {
        doDeleteOrUndeletePartition(req, resp, true);
      }
    });
    actions.put("undelete_partition", new Action() {
      @Override
      protected void action(HttpServletRequest req, HttpServletResponse resp) throws IOException {
        doDeleteOrUndeletePartition(req, resp, false);
      }
    });
    actions.put("clear_command_queue", new Action() {
      @Override
      protected void action(HttpServletRequest req, HttpServletResponse resp) throws IOException {
        doClearCommandQueue(req, resp);
      }
    });
    actions.put("discard_current_command", new Action() {
      @Override
      protected void action(HttpServletRequest req, HttpServletResponse resp) throws IOException {
        doDiscardCurrentCommand(req, resp);
      }
    });
    actions.put("update", new Action() {
      @Override
      protected void action(HttpServletRequest req, HttpServletResponse resp) throws IOException {
        doUpdate(req, resp);
      }
    });
  }

  protected void doDiscardCurrentCommand(HttpServletRequest req, HttpServletResponse resp) throws IOException {
    RingGroup rg = coordinator.getRingGroup(req.getParameter("g"));
    Ring r = rg.getRing(Integer.parseInt(req.getParameter("n")));
    Host h = r.getHostByAddress(PartitionServerAddress.parse(URLEnc.decode(req.getParameter("h"))));
    h.nextCommand();
    redirectBack(resp, rg, r, h);
  }

  protected void doClearCommandQueue(HttpServletRequest req, HttpServletResponse resp) throws IOException {
    RingGroup rg = coordinator.getRingGroup(req.getParameter("g"));
    Ring r = rg.getRing(Integer.parseInt(req.getParameter("n")));
    Host h = r.getHostByAddress(PartitionServerAddress.parse(URLEnc.decode(req.getParameter("h"))));
    h.clearCommandQueue();

    redirectBack(resp, rg, r, h);
  }

  private void redirectBack(HttpServletResponse resp, RingGroup rgc, Ring rc, Host hc) throws IOException {
    resp.sendRedirect(String.format("/host.jsp?g=%s&r=%s&h=%s", rgc.getName(), rc.getRingNumber(),
        URLEnc.encode(hc.getAddress().toString())));
  }

  protected void doEnqueueCommand(HttpServletRequest req, HttpServletResponse resp) throws IOException {
    RingGroup rg = coordinator.getRingGroup(req.getParameter("g"));
    Ring r = rg.getRing(Integer.parseInt(req.getParameter("n")));
    Host h = r.getHostByAddress(PartitionServerAddress.parse(URLEnc.decode(req.getParameter("h"))));
    h.enqueueCommand(HostCommand.valueOf(req.getParameter("command")));

    redirectBack(resp, rg, r, h);
  }

  private void doDeleteOrUndeletePartition(HttpServletRequest req, HttpServletResponse resp, boolean deletable) throws IOException {
    RingGroup rg = coordinator.getRingGroup(req.getParameter("g"));
    Ring r = rg.getRing(Integer.parseInt(req.getParameter("n")));
    Host h = r.getHostByAddress(PartitionServerAddress.parse(URLEnc.decode(req.getParameter("h"))));
    HostDomain hd = h.getHostDomain(coordinator.getDomain(req.getParameter("d")));
    HostDomainPartition hdp = hd.getPartitionByNumber(Integer.parseInt(req.getParameter("p")));
    hdp.setDeletable(deletable);

    redirectBack(resp, rg, r, h);
  }

  private void doUpdate(HttpServletRequest req, HttpServletResponse resp) throws IOException {
    RingGroup rg = coordinator.getRingGroup(req.getParameter("g"));
    Ring r = rg.getRing(Integer.parseInt(req.getParameter("n")));
    Host h = r.getHostByAddress(PartitionServerAddress.parse(URLEnc.decode(req.getParameter("h"))));
    h.setFlags(Hosts.splitHostFlags(req.getParameter("hostFlags")));
    PartitionServerAddress address = PartitionServerAddress.parse(req.getParameter("hostAddress"));
    if (!h.getAddress().equals(address)) {
      h.setAddress(address);
      // Redirect to Ring (host address has changed)
      resp.sendRedirect("/ring.jsp?g=" + rg.getName() + "&n=" + r.getRingNumber());
    } else {
      redirectBack(resp, rg, r, h);
    }
  }

  public static String getHostUrl(RingGroup ringGroup, Ring ring, Host host) {
    return "host.jsp?g=" + URLEnc.encode(ringGroup.getName())
        + "&r=" + ring.getRingNumber()
        + "&h=" + URLEnc.encode(host.getAddress().toString());
  }
}