BootstrapFileChecker.java

package com.hubspot.baragon.agent.lbs;

import java.util.Collection;
import java.util.concurrent.Callable;

import com.google.common.base.Optional;
import com.hubspot.baragon.models.BaragonConfigFile;
import com.hubspot.baragon.models.BaragonServiceState;
import com.hubspot.baragon.models.ServiceContext;
import org.apache.commons.lang3.tuple.ImmutablePair;
import org.apache.commons.lang3.tuple.Pair;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class BootstrapFileChecker implements Callable<Optional<Pair<ServiceContext, Collection<BaragonConfigFile>>>> {
  private static final Logger LOG = LoggerFactory.getLogger(BootstrapFileChecker.class);

  private final FilesystemConfigHelper configHelper;
  private final BaragonServiceState serviceState;
  private final long now;

  public BootstrapFileChecker(FilesystemConfigHelper configHelper,
                              BaragonServiceState serviceState,
                              long now) {

    this.configHelper = configHelper;
    this.serviceState = serviceState;
    this.now = now;
  }

  @Override
  public Optional<Pair<ServiceContext, Collection<BaragonConfigFile>>> call() {
    try {
      ServiceContext context = new ServiceContext(serviceState.getService(), serviceState.getUpstreams(), now, true);
      Optional<Collection<BaragonConfigFile>> maybeConfigsToApply = configHelper.configsToApply(context);
      if (maybeConfigsToApply.isPresent()) {
        Pair<ServiceContext, Collection<BaragonConfigFile>> configMap = new ImmutablePair<>(context, maybeConfigsToApply.get());
        return Optional.of(configMap);
      }
    } catch (Exception e) {
      LOG.error(String.format("Caught exception while finding config for %s", serviceState.getService()), e);
    }
    LOG.info(String.format("Don't need to apply %s", serviceState.getService().getServiceId()));
    return Optional.absent();
  }
}