Apache Tamaya - Proposal

Abstract

Tamaya is a highly flexible configuration solution based on an modular, extensible and injectable key/value based design, which should provide a minimal but extendible modern and functional API leveraging SE, ME and EE environments.

Tamaya hereby translates into in the middle, which is exactly, what configuration should be. It should be in the middle between your code and your runtime.

NOTE: Alternative names could be Mahkah=earth, Dakota=friend or Orenda=magic force.

Proposal

Tamaya is a highly flexible configuration API based on an modular, extensible and injectable key/value based design. The basic building blocks hereby are:

The API's focus is on simplicity and ease of use. Developers should only have to know a minimal set of artifacts to work with the solution. The API is built on latest Java 8 features and therefore fit perfectly with the functional features of Java 8.

Additionally Apache Tamaya will provide

Background

There is a global initiative running now for about a year lead by Anatole Tresch (Credit Suisse) with the target of standardizing configuration in Java EE and SE. Due to several reasons it seems currently most sensible to start an OSS project on the topic to join forces that actively want to contribute to the project. It is highly probably that standardization will be restarted at a later point once we have a widely used Apache standard. For further information you may look at http://javaeeconfig.blogspot.com .

Rationale

Configuration is one of the most cross-cutting concerns, which still lacks of a standard. Java EE is currently (EE7) in most areas strictly only configurable during build time of the deployed artifacts. Especially dynamic provisioning of resources or runtime configuration is not supported and in many cases impossible to add without tweaking the underlying application server. On the other hand running two separate configuration solutions for Java EE and Java SE as well make no or little sense. So it would be important we have a unified configuration model at hand, that is flexible enough, so

Initial Goals

The initial goals of the Apache Tamaya project are to:

Current Status

There is an existing running code base implementing a significant part of the features mentioned already at https://github.com/java-config and licensed under Apache v2.0, which will be contributed into the incubator. The separation between API and implementation hereby should stay enforced, since

Meritocracy

We plan to do everything possible to encourage an environment that supports a meritocracy. We did the same as well with JSR 354, were people throughout the world helped us to get the RI/TCK at a very good level. Similarly, whenever possible, we encouraged people to join the expert group, so they also would be capable of contributing to the API directly. In all cases we discussed all questions amd feedback transparently regardless if it was an EG member or just a member of Hackday, Hackergarten.

Community

The project initiative already is significantly supported by JUGs such as SouJava, LJC, iJUG, Berlin Brandenburg JUG, JUG Zurich, as well as companies such as Credit Suisse and Walmart. It is expected that support will raise very quickly so the library will evolve and be widely used as well.

Core Developers

The core team will be a set of well known experts from the Java SE and EE area (in random order):

It is expected that more people will join the incubator once it's running:

Alignment

Credit Suisse, which lead the initiative through Anatole Tresch during the last year, has a strong commitment to Open Source Software. As a consequence also their first JSR (354, Money & Currency) was released under Apache v2. The same is the case for all other core contributors and supporters.

Known Risks

Main Risk could be that main committers could cease the project before it is possible to build up a public community. Nevertheless the wide support of JUGs and companies involved already as well as the engagement of main drivers of the initiatives during the last year makes this not a very probable scenario.

Orphaned products

See main risks. Basically the engagement of all stakeholders (Credit Suisse, JUGs, other companies) should ensure this initiative will evolve hopefully rather quickly to a key component in the Java eco-system, both in SE, as well as ME and EE. Additionally all stakeholders involved (companies, as well as individuals/JUGs) have direct benefits of the functionality provided.

Inexperience with Open Source

Starting point will be the experimental repository at https://github.com/java-config. Additionally the talks given by Anatole (e.g. at Javaone 2014) and the blogs under http://javaeeconfig.blogspot.com help to give a good starting point on some of the concepts implemented/contributed. Nevertheless the idea is that the ideas are further evolved, basically similar to a JSR, to ensure all relevant views and aspects will be included.

All of the core committers have already experience working on open source projects or JSRs. Many of them even already are members of the ASF.

Homogenous Developers

The current list of committers includes developers from several different companies plus many independent volunteers. The committers are geographically distributed across the U.S., Brazil, Europe, and Asia. They are experienced with working in a distributed environment.

Reliance on Salaried Developers

Some of the developers are paid partially by their employer to contribute to this project, but given the anticipation from the Java community for a powerful Configuration implementation and the committers' sense of ownership for the code, the project would continue without issue if no salaried developers contributed to the project. Anatole, as the main committer and driver of the initiative currently, is paid only partially and basically drives the initiative as part of his community engagement in general already as of now.

Relationships with Other Apache Products

The project's core API will be independent of any other projects, because

Tamaya will provide a minimal standalone implementation as well. Nevertheless it will be possible that other solutions implement the API as well, e.g. Apache Commons Configuration (especially version 2). The API/SPI should be build in a way, so features from other solutions such as

can be used or even be leveraged (e.g. by adding environment dependent configuration instance management).

Tamaya will also provide adapter modules for other technologies/projects, so the solution can inter-operate with existing frameworks and solutions as a provider similarly. This explicitly also includes the possibility to use Tamaya as a configuration/property source for.

Integration into Java EE has to be coordinated with Apache Deltaspike Configuration, to avoid two conflicting configuration standards for Java EE.

An Excessive Fascination with the Apache Brand

While we expect the Apache brand may help attract more contributors, our interests is in establishing a powerful and widely used standard for configuration. At a later stage, if successful, standardizing it within a JSR also may be an option. We believe this process starts with growing a strong and self-managed community that can someday lead the charge in any future standardization efforts. Furthermore, we have been enthusiastic users of Apache and feel honored at getting the opportunity to join and learn.

Documentation

References to further reading material.

  \[1\] Java (EE) Configuration Blog:
    http://javaeeconfig.blogspot.com

  \[2\] Java Configuration Experimental Repo:
    https://github.com/java-config

  \[3\] The [JavaOne] Presentation Slideset:
    http://de.slideshare.net/AnatoleTresch/a-first-drat-to-java-configuration

Links to some other existing solutions:

  \[4\] Apache Commons Configuration: http://commons.apache.org/proper/commons-configuration/

  \[5\] Apache Deltaspike Configuration: https://deltaspike.apache.org/documentation/configuration.html

  \[6\] Spring Configuration: http://projects.spring.io/spring-framework/
      http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/context/annotation/PropertySource.html

  \[7\] Java Configuration Builder: https://github.com/TNG/config-builder

  \[8\] JFig: http://jfig.sourceforge.net/

  \[9\] Owner: http://owner.aeonbits.org/

Initial Source

Initial source will be from https://github.com/java-config . Most of the functionalities are already fully functional, documentation must be improved.

It is already licensed under Apache v2.

External Dependencies

The following external dependencies have been identified:

The core functionality will be dependent on/use

The parts requiring EE will probably make us of

The API part of the current initial source is completely standalone (it does not have any further dependencies than the JDK). The SE 8 based part does mainly depend on Apache commons-logging for logging.

Cryptography

The framework will not bring along additional cryptographic algorithms.

Required Resources

Mailing lists

We initially would like to start with the minimum required lists:

Git Repository

It is proposed that the source code for the Apache Tamaya project be hosted in the Apache Git repository:

Issue Tracking

The following JIRA project would be required to track issues for the Apache Tamaya project:

Other Resources

None.

Initial Committers

Affiliations

Sponsors

Champion:

Sponsors:

Nominated Mentors

Sponsoring Entity

We would like Apache Incubator to sponsor this project.