Contribution guidelines

This document describes the guidelines to contribute to Short Time Historic (STH) - Comet. If you are planning to contribute to the code you should read this document and get familiar with its content.

Ground rules & expectations

Before we get started, here are a few things we expect from you (and that you should expect from others):

  • Be kind and thoughtful in your conversations around this project. We all come from different backgrounds and projects, which means we likely have different perspectives on "how open source is done." Try to listen to others rather than convince them that your way is correct.
  • Please ensure that your contribution passes all tests. If there are test failures, you will need to address them before we can merge your contribution.
  • When adding content, please consider if it is widely valuable. Please don't add references or links to things you or your employer have created as others will do so if they appreciate it.
  • When reporting a vulnerability on the software, please, put in contact with STH Comet repository maintainers in order to discuss it in a private way.


Being an open source project, everyone can contribute, provided that you follow the next guidelines:

  • Before contributing any code, the author must make sure all the tests work (see below how to run the tests).
  • Developed code must adhere to the syntax guidelines enforced by the linters.
  • Code must be developed following the branching model and change log policies defined below.
  • For any new feature added, unit tests must be provided, taking as a reference the ones already created and included in the project.

To further guide you through your first contributions, we have created the label mentored which are assigned to those bugs and issues simple and interesting enough to be solved by people new to the project. Feel free to assign any of them to yourself and do not hesitate to mention any of the main developers (this is, @gtorodelvalle or @frbattid) in the issue's comments to get help from them during its resolution. They will be glad to help you.

How to contribute

In order to start contributing:

  1. Fork this repository clicking on the "Fork" button on the upper-right area of the page.
  2. Clone your just forked repository: bash git clone
  3. Add the main fiware-sth-comet repository as a remote to your forked repository (use any name for your remote repository, it does not have to be fiware-sth-comet, although we will use it in the next steps): bash git remote add fiware-sth-comet

Before starting your contribution, remember to synchronize the master branch in your forked repository with the master branch in the main fiware-sth-comet repository following the next steps:

  1. Change to your local master branch (in case you are not in it already): bash git checkout master
  2. Fetch the remote changes: bash git fetch fiware-sth-comet
  3. Merge them: bash git rebase fiware-sth-comet/master

Contributions following these guidelines will be added to the master branch, and released in the next version. The release process is explained in the Releasing section below.

Coding guidelines


Uses the provided .eslintrc.json flag files. To check source code style, type

npm run lint

Branching model

There is one special branch in the repository:

  • master: it contains the last stable development code. New features and bugfixes are always merged to master until a new release is created and published.

Apart from the previous branches, there is another set of branches called release/X.Y.Z where the latest version of each release code can be found. To this regard, a release called X.Y.Z is created whenever a new version of the project is released pointing to the latest status of the corresponding release/X.Y.Z release branch.

In order to start developing a new feature or refactoring, a new branch should be created in your local forked repository following the next naming convention:

  • bug/<description>
  • feature/<description>
  • hardening/<description>
  • task/<description>

depending on the type of work.

Once the final code is available in the local forked repository branch, a Pull Request should be sent to the master branch in the fiware-sth-comet remote repository when a review process will start before its final landing. Remember to check both the linters and the tests before creating the Pull Request.

Change log

The project contains a version change log file, called CHANGES_NEXT_RELEASE, that can be found in the root of the project. Whenever a new feature or bug fix is going to be merged into master, a new entry should be added to this change log file. The new entry should contain the reference number of the issue it is solving (if any).

When a new version is released, the change log is cleared and remains fixed in the last commit of that version. The content of the change log is also moved to the release description in the GitHub release.

More on this in the Releasing section below.


The test environment is preconfigured to run the Mocha Test Runner with support for the Should.js assertion Library .

Module mocking during testing can be done with proxyquire.

To run tests, type:

npm test

Continuous testing

Support for continuous testing by modifying a src file or a test. For continuous testing, type

npm run test:watch

If you want to continuously check also source code style, use instead:

npm run watch

Code coverage

A very good practice is to measure the code coverage of your tests.

To generate an HTML coverage report under site/coverage/ and to print out a summary, type

npm run test:coverage

Documentation guidelines


To check consistency of the Markdown markup, type

npm run lint:md


Uses the provided .textlintrc flag file. To check for spelling and grammar errors, dead links and keyword consistency, type

npm run lint:text


Removes node_modules and coverage folders, and package-lock.json file so that a fresh copy of the project is restored.

# Use git-bash on Windows
npm run clean

Prettify Code

Runs the prettier code formatter to ensure consistent code style (whitespacing, parameter placement and breakup of long lines etc.) within the codebase. Uses the prettierrc.json flag file. The codebase also offers an .editorconfig to maintain consistent coding styles across multiple IDEs.

# Use git-bash on Windows
npm run prettier

To ensure consistent Markdown formatting run the following:

# Use git-bash on Windows
npm run prettier:text


The process of making a release consists of the following steps and should only be made by any of the owners or administrators of the main repository:

  1. Synchronize the master branch in your local forked repository to the latest version of the master branch of the remote fiware-sth-comet repository as indicated in the How to contribute section above.
  2. From the updated master branch in your local forked repository, create a new task branch changing the development version number in the package.json file (currently it should include a -next suffix) to the new version to be released (X.Y.Z, for example, without any suffix).
  3. Create a pull request from this task branch to the master branch in the fiware-sth-comet remote repository and ask any of the additional project administrators to review it and to land it.
  4. In the fiware-sth-comet main repository, create a release branch named release/X.Y.Z from the latest version of the master branch using the corresponding version number.
  5. In the fiware-sth-comet main repository, create a new release setting the tag version to X.Y.Z from the new release branch release/X.Y.Z and publish it.
  6. Synchronize the master branch in your local forked repository to the latest version of the master branch of the remote fiware-sth-comet repository as indicated in the How to contribute section above.
  7. From the updated master branch in your local forked repository, create a new task branch and add the -next suffix to the current version number in the package.json file (to signal this as the development version) and remove the contents of the CHANGES_NEXT_RELEASE change log file.
  8. Create a pull request from this new task branch to the master branch in the remote fiware-sth-comet repository.

Version/release numbers

The version numbers will change for each release according to the following rules:

  • All version numbers will always follow the common pattern: X.Y.Z
  • X will change only when there are changes in the release breaking backwards compatibility or when there are very important changes in the feature set of the component. If X changes, Y should be set to 0.
  • Y will change every time a new version is released. If only Y changes, it means some new features or bug fixes have been released, but the component is just an improved version of the current major (X) release.
  • Z will increment its value as new bugfixes are detected and fixed for each major (X) and minor (Y) release.

Between releases, the version number in the master branch will be X.Y.Z-next (where X.Y.Z is the latest stable release), indicating that it is a development version.