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From Apache Wiki <>
Subject [Incubator Wiki] Update of "GoraProposal" by EnisSoztutar
Date Mon, 13 Sep 2010 12:29:03 GMT
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The "GoraProposal" page has been changed by EnisSoztutar.


New page:
= 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
(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 [[]]  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 [[]].
 * Wiki pages can be found at [[]].
 * List of issues can be found at  [[]].
 * Current web address: [[]].
 * Current email address: 

== 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’s sponsorship. 

The code can be found at [[]].

== External Dependencies ==
External dependencies excluding Apache projects are as follows
 * JDOM - -  Apache-style license
 * SQL Builder - - Artistic License, LGPL. SQL
Builder is intended to be removed from the source due to technical reasons anyway.
 * HSQLDB - - BSD-style license
 * JUnit - - Common Public License 1.0
 * SLF4J - - MIT License
 * Google Guava Libraries - - Apache License 2.0

== Required Resources ==

=== Mailing Lists ===

 * gora-private (with moderated subscriptions)
 * gora-dev
 * gora-commits
 * gora-user

=== Subversion Directory ===

 * [[]]

=== Issue Tracking ===

=== Other Resources ===
We need a wiki at 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

== Initial Committers ==

 || '''Name'''       || '''email'''                || '''Affiliation''' || '''Timezone'''
 || Enis Söztutar    || enis [at]       || Konneka           || +3   ||
 || Doğacan Güney    || dogacan [at]    || Konneka           || +3   ||
 || Sertan Alkan     || sertanalkan [at] || Konneka           || +3   ||
 || Julien Nioche    || jnioche [at]    || DigitalPebble     || +1   ||
 || Andrzej Bialecki || ab [at]         || Sigram            ||      ||

=== Affiliations ===
All of the parties are affiliated with open source consulting shops. Most of the development
was sponsored by, 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
Hadoop, since most of the community is projected to overlap. 

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