The EnergyPlus team welcomes your contribution to the project. Since EnergyPlus is open source, user submissions of code, documentation, or any other kind of contribution moves the project forward. If you contribute code, you agree that your contribution may be incorporated into EnergyPlus and made available under the EnergyPlus license on the internet or via other applicable means.
The contribution process for EnergyPlus is composed of three steps:
- Send consent email
In order for us to distribute your code as part of EnergyPlus under the EnergyPlus license, we’ll need your consent. An email acknowledging understanding of these terms and agreeing to them is all that will be asked of any contributor. Send an email to the EnergyPlus project manager (see below for the address) including the following text and a list of co-contributors (if any):
I agree to contribute to EnergyPlus. I agree to the following terms and conditions for my contributions: First, I agree that I am licensing the copyright to my contributions under the terms of the current EnergyPlus license. Second, I hereby grant to Alliance for Sustainable Energy, LLC, to any successor manager and distributor of EnergyPlus appointed by the U.S. Department of Energy, and to all recipients of a version of EnergyPlus that includes my contributions, a non-exclusive, worldwide, royalty-free, irrevocable patent license under any patent claims owned by me, or owned by my employer and known to me, that are or will be, necessarily infringed upon by my contributions alone, or by combination of my contributions with the version of EnergyPlus to which they are contributed, to make, have made, use, offer to sell, sell, import, and otherwise transfer any version of EnergyPlus that includes my contributions, in source code and object code form. Third, I represent and warrant that I am authorized to make the contributions and grant the foregoing license(s). Additionally, if, to my knowledge, my employer has rights to intellectual property that covers my contributions, I represent and warrant that I have received permission to make these contributions and grant the foregoing license(s) on behalf of my employer.
Once we have your consent on file, you’ll only need to redo it if conditions change (e.g. a change of employer).
- Scope agreement and timeline commitment
If your contribution is small (e.g. a bug fix), simply submit your contribution via GitHub. If your contribution is larger (e.g. a new feature), we’ll need to evaluate your proposed contribution. To do that, we need a written description of why you wish to contribute to the EnergyPlus, a detailed description of the project that you are proposing, the precise functionalities that you plan to implement as part of the project, and a timeframe for implementation (see the template contribution proposal document). After we review your materials, we will schedule a meeting or conference call to discuss your information in more detail. We may ask you to revise your materials and make changes to it, which we will re-review. Before you do any work we must reach prior agreement and written approval on project areas, scope, timeframe, expected contents, and functionalities to be addressed.
- Technical contribution process
We want EnergyPlus to adhere to our established quality standards. As such, we ask that you follow our Agile development process - particularly with respect to coding standards, code review, unit tests, and code coverage. These items are explained further below. Smaller, non-code contributions may not require as much review as code contributions, but all contributions will be reviewed. Code contributions will initially be in a source control branch, and then will be merged into the official EnergyPlus repository after review and approval. Any bugs, either discovered by you, us, or any users will be tracked in our bug tracker. We request you that you take full responsibility for correcting bugs. Be aware that, unless notified otherwise, the correction of bugs takes precedence over the submission or creation of new code.
Release Schedule - Contributions should be aligned with the EnergyPlus release schedule. EnergyPlus is released publicly twice each year (approximately on the last workday of March and September). There are cutoff dates for when new contributions are allowed for the upcoming release (approximately February 15 and August 15). If your contribution is incomplete or comes in past the cutoff date for a release, we reserve the right to hold your code for a later release.
Agile Development Process - Work items are tracked and planned as Agile tasks and/or defects. You will be given user credentials to source control and Pivotal Tracker. Your work plan will be entered in Pivotal Tracker and tracked as Agile tasks in Pivotal. Our Agile development cycle (called iteration) is two weeks long, and you will be asked for progress and completion of your tasks planned for the iteration, according to the timeline for the project. A review of your contribution will start when the status of your Pivotal task is marked as “accept”.
Coding Standards - We will point you to coding guidelines to help you with writing EnergyPlus code. Although these standards are not complete or very detailed, they should give you an idea of the style that we would like you to adopt. New additions to EnergyPlus must be written using object-oriented programming techniques and practices. Please also look at the EnergyPlus code itself as an example of the preferred coding style.
Code Reviews - You will be working and testing your code in a source control branch. When a piece of functionality is complete, tested and working, let us know and we will review your code. If the functionality that you contributed is complex, we will ask you for a written design document as well. We want your code to follow coding standards, be clear, readable and maintainable, and of course it should do what it is supposed to do. We will look for errors, style issues, comments (or lack thereof), and any other issues in your code. We will inform you of our comments and we expect you to make the recommended changes. New re-reviews may be expected until the code complies with our required processes.
Unit Tests - We ask that you supply unit tests along with the code that you have written. A unit test is a program that exercises your code in isolation to verify that it does what it is supposed to do. Your unit tests are very important to us. First, they give an indication that your code works according to its intended functionality. Second, we execute your unit tests automatically along with our unit tests to verify that the overall EnergyPlus code continues to work. You will need to write and submit Google Unit Tests (GTests) along with your code before a code review is scheduled.
Code Coverage - We require that your unit tests provide an adequate coverage of the source code you are submitting. You will need to design your unit tests in a way that all critical parts of the code (at least) are tested and verified. A good rule of thumb for code coverage is 70% or greater. There are tools to help you on code coverage.
Documentation - Proper documentation is crucial for our users, without it users will not know how to use your contribution. We require that you create user documentation so that end users know how to use your new functionality.
For further questions or information:
Luigi Gentile Polese
EnergyPlus Project Management
EnergyPlus is funded by the U.S. Department of Energy’s (DOE) Building Technologies Office (BTO), and managed by the National Renewable Energy Laboratory (NREL).
EnergyPlus is developed in collaboration with NREL, various DOE National Laboratories, academic institutions, and private firms.