com.hmsonline.cassandra.triggers.TriggerStore Maven / Gradle / Ivy

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package com.hmsonline.cassandra.triggers;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.cassandra.thrift.ColumnOrSuperColumn;
import org.apache.cassandra.thrift.ColumnParent;
import org.apache.cassandra.thrift.ConsistencyLevel;
import org.apache.cassandra.thrift.KeyRange;
import org.apache.cassandra.thrift.KeySlice;
import org.apache.cassandra.thrift.SlicePredicate;
import org.apache.cassandra.thrift.SliceRange;
import org.apache.cassandra.utils.ByteBufferUtil;
import org.apache.commons.lang.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class TriggerStore extends CassandraStore {
  private static Logger logger = LoggerFactory.getLogger(TriggerStore.class);

  public static final String KEYSPACE = "triggers";
  public static final String COLUMN_FAMILY = "Triggers";
  public static final String ENABLED = "enabled";
  public static final String PAUSED = "PAUSED";
  private static TriggerStore instance = null;

  public TriggerStore(String keyspace, String columnFamily) throws Exception {
    super(keyspace, columnFamily);
    logger.debug("Instantiated trigger store.");
  }

  public static synchronized TriggerStore getStore() throws Exception {
    if (instance == null)
      instance = new TriggerStore(KEYSPACE, COLUMN_FAMILY);
    return instance;
  }

  @SuppressWarnings("unchecked")
  public static Trigger getTrigger(String triggerClass) throws Exception {
    Class clazz = (Class) Class.forName(triggerClass);
    return clazz.newInstance();
  }

  public Map> getTriggers() throws Exception {
    // TODO: Cache this.
    Map> triggerMap = new HashMap>();
    SlicePredicate predicate = new SlicePredicate();
    SliceRange range = new SliceRange(ByteBufferUtil.bytes(""), ByteBufferUtil.bytes(""), false, 10);
    predicate.setSlice_range(range);

    KeyRange keyRange = new KeyRange(1000);
    keyRange.setStart_key(ByteBufferUtil.bytes(""));
    keyRange.setEnd_key(ByteBufferUtil.EMPTY_BYTE_BUFFER);
    ColumnParent parent = new ColumnParent(COLUMN_FAMILY);
    List rows = getConnection(KEYSPACE).get_range_slices(parent, predicate, keyRange,
                                                                   ConsistencyLevel.ALL);
    for (KeySlice slice : rows) {
      String columnFamily = ByteBufferUtil.string(slice.key);
      triggerMap.put(columnFamily, processRow(slice));
    }
    return triggerMap;
  }

  @SuppressWarnings({
      "unchecked", "rawtypes"
  })
  private List processRow(KeySlice slice) throws Exception {
    List triggers = new ArrayList();
    for (ColumnOrSuperColumn column : slice.columns) {
      String className = ByteBufferUtil.string(column.column.name);
      String enabled = ByteBufferUtil.string(column.column.value);
      if (PAUSED.equals(StringUtils.upperCase(className)) && ENABLED.equals(enabled)) {
        return new ArrayList(Arrays.asList(new Trigger[] {
            new PausedTrigger()
        }));
      }
      else if (enabled.equals(ENABLED)) {
        triggers.add(getTrigger(className));
      }
    }
    return triggers;
  }
}