Hi all,
We would like to announce the Proposal for Gora, an ORM for Colum Stores,
for the Apache Incubation. We believe that Gora can find a nice home at
Apache.
Wiki of the proposal can be found at
http://wiki.apache.org/incubator/GoraProposal
The proposal is as below.
= Gora Proposal for Apache Incubation =
== Abstract ==
Gora is an ORM framework for column stores such as Apache HBase and Apache
Cassandra with a specific focus on Hadoop.
== Proposal ==
Although there are various excellent ORM frameworks for relational
databases, data modeling in NoSQL data stores differ profoundly from their
relational cousins. Moreover, data-model agnostic frameworks such as JDO are
not sufficient for use cases, where one needs to use the full power of the
data models in column stores. Gora fills this gap by giving the user an
easy-to-use ORM framework with data store specific mappings and built in
Apache Hadoop support.
The overall goal for Gora is to become the standard data representation and
persistence framework for big data. The roadmap of Gora can be grouped as
follows.
* Data Persistence : Persisting objects to Column stores such as HBase,
Cassandra, Hypertable; key-value stores such as Voldermort, Redis, etc; SQL
databases, such as MySQL, HSQLDB, flat files in local file system of Hadoop
HDFS.
* Data Access : An easy to use Java-friendly common API for accessing the
data regardless of its location.
* Indexing : Persisting objects to Lucene and Solr indexes,
accessing/querying the data with Gora API.
* Analysis : Accesing the data and making analysis through adapters for
Apache Pig, Apache Hive and Cascading
* MapReduce support : Out-of-the-box and extensive MapReduce (Apache
Hadoop) support for data in the data store.
== Background ==
ORM stands for Object Relation Mapping. It is a technology which abstacts
the persistency layer
(mostly Relational Databases) so that plain domain level objects can be
used, without the cumbersome effort to save/load the data to and from the
database. Gora differs from current solutions in that:
* Gora is specially focussed at NoSQL data stores, but also has limited
support for SQL databases
* The main use case for Gora is to access/analyze big data using Hadoop.
* Gora uses Avro for bean definition, not byte code enhancement or
annotations
* Object-to-data store mappings are backend specific, so that full data
model can be utilized.
* Gora is simple since it ignores complex SQL mappings
* Gora will support persistence, indexing and anaysis of data, using Pig,
Lucene, Hive, etc
== Rationale ==
ORM frameworks are nothing new. But with the explosion of data generated in
Terabytes and even Petabytes, NoSQL data stores are gaining ever-increasing
popularity. Coupled with limited support to already-proven Apache Hadoop
support in current ORM frameworks, there was a need for a new project.
Gora is currently hosted at Github. However, Gora has ties to ASF in many
ways. As detailed in the proposal section, Gora will be a high level client
for many Apache projects and subprojects including Hadoop(common, hdfs, and
mapreduce), HBase, Cassandra, Avro, Lucene, Solr, Pig, and Hive. Gora
already uses Hadoop, HBase, Cassandra and Avro. Moreover, Gora started its
life inside Apache Nutch project, and now Nutch trunk uses Gora as a
library. Even more, the initial set of committers are all ASF members.
Therefore, we think that Apache will be an excellent home for Gora.
== Initial Goals ==
Initial goals for Gora can be summarized as:
* Iron out the remaining issues with HBase, Cassandra and SQL support.
* Make the first release before the end of the year.
* Improve documentation
* Support for Cascading
== Current Status ==
=== Meritocracy ===
Current commit rights belong to the initial list of committers four of who
are also ASF members. All the developers have extensive experience with
Apache projects. We honor the meritocracy policy of ASF foundation.
=== Community ===
Gora’s community mostly overlap with that of Nutch, Hadoop, HBase, Avro and
Cassandra. We
have a small community for now (5 initial committers, 18 people tracking the
project at Github), but have been piggybacking the Nutch community for a
while. If Gora is accepted to Apache Incubator, we expect more traction.
Moreover, with the increasing popularity of NoSQL databases, we expect more
users.
=== Core Developers ===
Gora was started by the initial code base inside Apache Nutch by Doğacan
Güney. Then Enis Söztutar has refactored and re-architected the project out
of Nutch. Later Julien Nioche, Andrzej Bialecki and Doğacan has ported Nutch
to use the newly formed project. Later, Sertan Alkan has joined. Doğacan and
Julien are Nutch PMC members, Andrzej is the Nutch PMC chair. Enis is an
Apache Hadoop PMC member.
=== Alignment ===
As discusssed in the second paragraph of Rationale Section, all of the
current developers are Apache people, and four of them are PMC members,
which shows that we have some experience with the Apache way. Moreover, Gora
is tightly related with lots of Apache projects, Nutch, Hadoop, HBase,
Cassandra, Avro, Pig, Hive, Lucene to name a few. Gora has started its life
inside Nutch, and now nutch trunk uses Gora to persist web crawl data to
HBase, Cassandra and MySQL, which means that Gora is a very critical
component in Nutch.
== Known Risks ==
=== Orphaned Products ===
Most of the development depends on Enis and Doğacan for now. Both of them
intent to continue Gora development. However, we also acknowledge that more
core developers are needed for the project to be truly successful. The
general strategy to acquire more developers will be to acquire more users,
and encourage users to be active in the community and develop patches.
Moreover, the next release of Nutch planned before the end of 2010 has
extensive Gora support. We expect more interest from Nutch community, and we
will continue to announce Gora notifications at Hadoop,HBase and Cassandra
mailing lists.
=== Inexperience with Open Source ===
We believe that all of the developers have extensive open source experience.
Four of the initial committers are apache members. The codebase is also open
source since April 2010. We also have some documentation, wiki pages, issue
tracker and dev mailing list.
=== Homogeneous Developers ===
We have a semi-distributed development environment where Doğacan, Enis and
Sertan share the same office, but Andrzej and Julien are independent. With
the aim of acquiring more developers, we expect more heterogeneous
development.
=== Reliance on Salaried Developers ===
Gora development have been supported by [[ant.com]] search engine as
contract work. It is expected that this contract will continue in the
future. However, even without sponsors, we are commited to continue on Gora
development, since we believe in the technology it brings and it’s vital
role in Nutch, and our other closed sourced projects.
=== Relationships with Other Apache Products ===
Gora will be tightly related to lots of Apache projects:
* Nutch : Apache nutch was to home to Gora’s initial code base. Now, Nutch
trunk uses Gora as a library. The next relase of Nutch, planned before the
end of 2010 will be using Gora’s first release.
* Hadoop : Gora has extensive support for Hadoop MapReduce Gora defines all
the necessary data structures for working with Hadoop .Data stored in column
oriented data stores can be analyzed with Gora using Hadoop.
* Avro : Gora uses and extends Avro. Data beans in Gora are defined using
Avro schemas ,and compiled into Java code with the extended version of the
Avro compiler. Avro is also used in data serialization.
* HBase : Gora supports HBase as a persistency backend.
* Cassandra : Gora support Cassandra as a persistency backend.
* Lucene/Solr : Gora intends to support Lucene/Solr as a persistency and
indexing backend.
* Pig : Gora intends to support Pig for data anaysis
* Hive : Gora intends to support Hive for data analysis
=== An Excessive Fascination with the Apache Brand ===
Gora is a natural fit for Apache due to it's current commiters and depending
projects.
== Documentation ==
* The project is currently hosted at http://github.com/enis/gora/.
* Wiki pages can be found at http://wiki.github.com/enis/gora/.
* List of issues can be found at http://github.com/enis/gora/issues/.
* Current web address: http://groups.google.com/group/gora-dev.
* Current email address: gora-...@googlegroups.com.
== Initial Source ==
The initial source was developed as a patch to the Apache Nutch project. But
the storage abstraction layer was orthogonal to the web crawler, and we
decided to extract it to a separate project with much wider goals. Thus
Gora, as a project, was born. The initial code is developed by Enis and
Dogacan with ant.com’s sponsorship.
The code can be found at http://github.com/enis/gora/.
== External Dependencies ==
External dependencies excluding Apache projects are as follows
* JDOM - http://jdom.org/ - Apache-style license
* SQL Builder - http://openhms.sourceforge.net/sqlbuilder/ - Artistic
License, LGPL. SQL Builder is intended to be removed from the source due to
technical reasons anyway.
* HSQLDB - http://hsqldb.org/ - BSD-style license
* JUnit - http://junit.org - Common Public License 1.0
* SLF4J - http://www.slf4j.org/ - MIT License
* Google Guava Libraries - http://code.google.com/p/guava-libraries/ -
Apache License 2.0
== Required Resources ==
=== Mailing Lists ===
* gora-private (with moderated subscriptions)
* gora-dev
* gora-commits
=== Subversion Directory ===
* [[http://svn.apache.org/repos/asf/incubator/gora]]
=== Issue Tracking ===
* JIRA (GORA)
=== Other Resources ===
We need a wiki at http://wiki.apache.org. Currently, we have a wiki at
Github, Since there is not a lot of pages there, we can manually move the
pages to the wiki at wiki.apache.org.
== Initial Committers ==
Name email
Affiliation Timezone
Enis Söztutar enis [at] apache.org Konneka +3
Doğacan Güney dogacan [at] apache.org Konneka +3
Sertan Alkan sertanalkan [at] gmail.com Konneka +3
Julien Nioche jnioche [at] apache.org DigitalPebble +1
Andrzej Bialecki ab [at] apache.org Sigram
=== Affiliations ===
All of the parties are affiliated with open source consulting shops. Most of
the development was sponsored by ant.com, however we expect that the amount
of volunteer work will increase, and more developers will come on board.
== Sponsors ==
=== Champion ===
* Chris Mattmann (mattmann AT apache DOT org)
=== Nominated Mentors ===
* Chris Mattmann (mattmann AT apache DOT org)
* Andrzej Bialecki (ab AT apache DOT org )
=== Sponsoring Entity ===
Apache Incubator. Successful graduation can result in either being a TLP, or
a subproject of
Hadoop, since most of the community is projected to overlap.
