# Contributing

BRouter is heavily based on the following libraries:

-   [Leaflet](leafletjs.com/) maps library, used in conjuction with many plugins.
-   [Bootstrap](https://getbootstrap.com/) design library.
-   [JQuery](https://jquery.com) javascript library.
-   [Node.js](https://nodejs.org/) and [Yarn](https://yarnpkg.com/en/).

## Install dependencies

```sh
yarn
```

## Build

```sh
#for development
yarn build debug

#for release
yarn build
```

## Develop

```sh
yarn serve
```

### Develop with Docker

```sh
#to install dependencies
docker-compose run --rm install

#to serve for development
docker-compose run --rm -p 3000:3000 serve

#or
docker-compose up serve
```

## Translations

`TL;DR` if you contribute to BRouter and add some translatable content, please make sure not to modify anything in `locales` folder, except `locales/en.json`. Full explanation below.

### How internationalization works

BRouter is translated using [i18next](https://www.i18next.com/) library, via command `gulp i18next`. It extracts translatable elements into `locales/en.json` file (English version). (Note that unused translation keys or keys not referenced in `keys.js` might get removed automatically. Make sure to commit any changes first before running this, and only amend the previous commit after checking the diff carefully.)

As soon as this file is modified, it must be uploaded by the maintainers to Transifex (manually) with the command `yarn push-transifex`.

Anyone can then translate BRouter directly on [Transifex](https://www.transifex.com/openstreetmap/brouter-web/) platform.

From time to time (eg. when preparing releases), we can update translated content with the command `yarn pull-transifex`. **It will overwrite all JSON files in `locales` directory**.

## License

BRouter is licensed under [MIT](LICENSE). Please make sure before adding any library that it is compatible with that. (GPL licenses are incompatible for instance).