code: @GET
    @Path(WEBUI_OVERVIEW)
    @ReturnType("alluxio.wire.WorkerWebUIOverview")
    public Response getWebUIOverview() {
      return RestUtils.call(() -> {
        WorkerWebUIOverview response = new WorkerWebUIOverview();
  
        response.setWorkerInfo(new UIWorkerInfo(mWorkerProcess.getRpcAddress().toString(),
            mWorkerProcess.getStartTimeMs(),
            ServerConfiguration.get(PropertyKey.USER_DATE_FORMAT_PATTERN)));
  
        BlockStoreMeta storeMeta = mBlockWorker.getStoreMeta();
        long capacityBytes = 0L;
        long usedBytes = 0L;
        Map<String, Long> capacityBytesOnTiers = storeMeta.getCapacityBytesOnTiers();
        Map<String, Long> usedBytesOnTiers = storeMeta.getUsedBytesOnTiers();
        List<UIUsageOnTier> usageOnTiers = new ArrayList<>();
        for (Map.Entry<String, Long> entry : capacityBytesOnTiers.entrySet()) {
          String tier = entry.getKey();
          long capacity = entry.getValue();
          Long nullableUsed = usedBytesOnTiers.get(tier);
          long used = nullableUsed == null ? 0 : nullableUsed;
  
          capacityBytes += capacity;
          usedBytes += used;
  
          usageOnTiers.add(new UIUsageOnTier(tier, capacity, used));
        }
  
        response.setCapacityBytes(FormatUtils.getSizeFromBytes(capacityBytes))
            .setUsedBytes(FormatUtils.getSizeFromBytes(usedBytes)).setUsageOnTiers(usageOnTiers)
            .setVersion(RuntimeConstants.VERSION);
  
        List<UIStorageDir> storageDirs = new ArrayList<>(storeMeta.getCapacityBytesOnDirs().size());
        for (Pair<String, String> tierAndDirPath : storeMeta.getCapacityBytesOnDirs().keySet()) {
          storageDirs.add(new UIStorageDir(tierAndDirPath.getFirst(), tierAndDirPath.getSecond(),
              storeMeta.getCapacityBytesOnDirs().get(tierAndDirPath),
              storeMeta.getUsedBytesOnDirs().get(tierAndDirPath)));
        }
  
        response.setStorageDirs(storageDirs);
  
        return response;
      }, ServerConfiguration.global());
    }
docs: Gets web ui overview page data.
  
  @return the response object