org.apache.storm.mongodb.bolt

Class MongoInsertBolt

java.lang.Object

org.apache.storm.topology.base.BaseComponent

org.apache.storm.topology.base.BaseRichBolt

org.apache.storm.mongodb.bolt.AbstractMongoBolt

org.apache.storm.mongodb.bolt.MongoInsertBolt

All Implemented Interfaces:

Serializable, IBolt, IComponent, IRichBolt

public class MongoInsertBolt
extends AbstractMongoBolt

Basic bolt for writing to MongoDB. Note: Each MongoInsertBolt defined in a topology is tied to a specific collection.

See Also:

Serialized Form

Field Summary

Fields inherited from class org.apache.storm.mongodb.bolt.AbstractMongoBolt

collector, mongoClient

Constructor Summary

Constructors

Constructor and Description
MongoInsertBolt(String url, String collectionName, MongoMapper mapper) MongoInsertBolt Constructor.

Method Summary

Modifier and Type	Method and Description
void	declareOutputFields(OutputFieldsDeclarer declarer) Declare the output schema for all the streams of this topology.
void	execute(Tuple tuple) Process a single tuple of input.
Map<String,Object>	getComponentConfiguration() Declare configuration specific to this component.
void	prepare(Map<String,Object> topoConf, TopologyContext context, OutputCollector collector) Called when a task for this component is initialized within a worker on the cluster.
MongoInsertBolt	withBatchSize(int batchSize)
MongoInsertBolt	withFlushIntervalSecs(int flushIntervalSecs)
MongoInsertBolt	withOrdered(boolean ordered)

Methods inherited from class org.apache.storm.mongodb.bolt.AbstractMongoBolt

cleanup

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

MongoInsertBolt

public MongoInsertBolt(String url,
                       String collectionName,
                       MongoMapper mapper)

MongoInsertBolt Constructor.

Parameters:

url - The MongoDB server url

collectionName - The collection where reading/writing data

mapper - MongoMapper converting tuple to an MongoDB document

Method Detail

execute

public void execute(Tuple tuple)

Description copied from interface: IBolt

Process a single tuple of input. The Tuple object contains metadata on it about which component/stream/task it came from. The values of the Tuple can be accessed using Tuple#getValue. The IBolt does not have to process the Tuple immediately. It is perfectly fine to hang onto a tuple and process it later (for instance, to do an aggregation or join).

Tuples should be emitted using the OutputCollector provided through the prepare method. It is required that all input tuples are acked or failed at some point using the OutputCollector. Otherwise, Storm will be unable to determine when tuples coming off the spouts have been completed.

For the common case of acking an input tuple at the end of the execute method, see IBasicBolt which automates this.

Parameters:

tuple - The input tuple to be processed.

withBatchSize

public MongoInsertBolt withBatchSize(int batchSize)

withOrdered

public MongoInsertBolt withOrdered(boolean ordered)

withFlushIntervalSecs

public MongoInsertBolt withFlushIntervalSecs(int flushIntervalSecs)

getComponentConfiguration

public Map<String,Object> getComponentConfiguration()

Description copied from interface: IComponent

Declare configuration specific to this component. Only a subset of the “topology.*” configs can be overridden. The component configuration can be further overridden when constructing the topology using TopologyBuilder

Specified by:

getComponentConfiguration in interface IComponent

Overrides:

getComponentConfiguration in class BaseComponent

prepare

public void prepare(Map<String,Object> topoConf,
                    TopologyContext context,
                    OutputCollector collector)

Description copied from interface: IBolt

Called when a task for this component is initialized within a worker on the cluster. It provides the bolt with the environment in which the bolt executes.

This includes the:

Specified by:

prepare in interface IBolt

Overrides:

prepare in class AbstractMongoBolt

Parameters:

topoConf - The Storm configuration for this bolt. This is the configuration provided to the topology merged in with cluster configuration on this machine.

context - This object can be used to get information about this task’s place within the topology, including the task id and component id of this task, input and output information, etc.

collector - The collector is used to emit tuples from this bolt. Tuples can be emitted at any time, including the prepare and cleanup methods. The collector is thread-safe and should be saved as an instance variable of this bolt object.

declareOutputFields

public void declareOutputFields(OutputFieldsDeclarer declarer)

Description copied from interface: IComponent

Declare the output schema for all the streams of this topology.

Parameters:

declarer - this is used to declare output stream ids, output fields, and whether or not each output stream is a direct stream