#MongoDB Connector for Hadoop
##Purpose
The MongoDB Connector for Hadoop is a library which allows MongoDB (or backup files in its data format, BSON) to be used as an input source, or output destination, for Hadoop MapReduce tasks. It is designed to allow greater flexibility and performance and make it easy to integrate data in MongoDB with other parts of the Hadoop ecosystem.
Current stable release: 1.2.0
- Can create data splits to read from standalone, replica set, or sharded configurations
- Source data can be filtered with queries using the MongoDB query language
- Supports Hadoop Streaming, to allow job code to be written in any language (python, ruby, nodejs currently supported)
- Can read data from MongoDB backup files residing on S3, HDFS, or local filesystems
- Can write data out in .bson format, which can then be imported to any MongoDB database with
mongorestore - Works with BSON/MongoDB documents in other Hadoop tools such as Pig and Hive.
See the release page.
The mongo-hadoop connector currently supports the following versions of hadoop: 0.23, 1.0, 1.1, 2.2, 2.3, and CDH 4. The default build
version will build against the last Apache Hadoop (currently 2.3). If you would like to build against a specific version of Hadoop you
simply need to pass -Phadoop_version=<your version>.
Then run ./gradlew jar to build the jars. The jars will be placed in to build/libs for each module. e.g. for the core module,
it will be generated in the core/build/libs directory.
After successfully building, you must copy the jars to the lib directory on each node in your hadoop cluster. This is usually one of the following locations, depending on which Hadoop release you are using:
$HADOOP_HOME/lib/$HADOOP_HOME/share/hadoop/mapreduce/$HADOOP_HOME/share/hadoop/lib/
###Apache Hadoop 1.0 Does not support Hadoop Streaming.
Build using -Phadoop_version=1.0
###Apache Hadoop 1.1 Includes support for Hadoop Streaming.
Build using -Phadoop_version=1.1
###Apache Hadoop 0.23 Includes support for Streaming
Build using -Phadoop_version=0.23
###Cloudera Distribution for Hadoop Release 4
This is the newest release from Cloudera which is based on Apache Hadoop 2.0. The newer MR2/YARN APIs are not yet supported, but MR1 is still fully compatible.
Includes support for Streaming.
Build with -Phadoop_version=cdh4
###Apache Hadoop 2.2 Includes support for Streaming
Build using -Phadoop_version=2.2
###Apache Hadoop 2.3 Includes support for Streaming
Build using -Phadoop_version=2.3
Amazon Elastic MapReduce is a managed Hadoop framework that allows you to submit jobs to a cluster of customizable size and configuration, without needing to deal with provisioning nodes and installing software.
Using EMR with the MongoDB Connector for Hadoop allows you to run MapReduce jobs against MongoDB backup files stored in S3.
Submitting jobs using the MongoDB Connector for Hadoop to EMR simply requires that the bootstrap actions fetch the dependencies (mongoDB
java driver, mongo-hadoop-core libs, etc.) and place them into the hadoop distributions lib folders.
For a full example (running the enron example on Elastic MapReduce) please see here.
Documentation on Pig with the MongoDB Connector for Hadoop.
For examples on using Pig with the MongoDB Connector for Hadoop, also refer to the examples section.
If your code introduces new features, please add tests that cover them if possible and make sure that ./gradlew check still passes.
If you're not sure how to write a test for a feature or have trouble with a test failure, please post on the google-groups with details
and we will try to help.
Justin lee (justin.lee@mongodb.com)
- Mike O'Brien (mikeo@10gen.com)
- Brendan McAdams brendan@10gen.com
- Eliot Horowitz erh@10gen.com
- Ryan Nitz ryan@10gen.com
- Russell Jurney (@rjurney) (Lots of significant Pig improvements)
- Sarthak Dudhara sarthak.83@gmail.com (BSONWritable comparable interface)
- Priya Manda priyakanth024@gmail.com (Test Harness Code)
- Rushin Shah rushin10@gmail.com (Test Harness Code)
- Joseph Shraibman jks@iname.com (Sharded Input Splits)
- Sumin Xia xiasumin1984@gmail.com (Sharded Input Splits)
- Jeremy Karn
- bpfoster
- Ross Lawley
- Carsten Hufe
- Asya Kamsky
- Thomas Millar
Issue tracking: https://jira.mongodb.org/browse/HADOOP/
Discussion: http://groups.google.com/group/mongodb-user/