The dashboard provides information on the outbreak and prevalence of COVID-19 in The Netherlands. It combines measured and modelled data from various sources to give a broad perspective on the subject.
If you want to contact the dashboard team, feel free to open an issue for technical questions, bug reports or security findings. If you have a generic question or remark about the corona policy of the Dutch government, please consult the frequently asked questions or contact page on the dashboard.
The core team works directly from this open-source repository. If you plan to propose changes, we recommend opening an issue beforehand where we can discuss your planned changes. This increases the chance that we might be able to use your contribution (or it avoids doing work if there are reasons why we wouldn't be able to use it).
The project is set up as a monorepo and therefore the code is organized in multiple packages.
app
: The main application that contains the front-end part of the dashboard. READMEcli
: Command-line tools for things like data validation.cms
: Configurations for the Sanity content management system. READMEcommon
: Commonly shared code that multiple packages are using, like types and utils.e2e
: End-to-end tests using Cypressicons
: A React icon component library, used by the CMS and by app
You can run these commands to quickly get started. We advise you to read what's happening behind the scenes by reading the app README
$ yarn
$ yarn bootstrap
$ yarn dev
In this project we use Yarn instead of NPM, so the documentation assumes you
have the yarn
executable installed on your system.
If you would like to run the code on your local machine check out the readme documentation of the app and (optionally the) cms packages.
Without describing in detail all the rules we tend to follow here are some worth noting:
- All filenames are written in kebab-case.
- We use named exports where possible. They improve typing, help refactoring and allow us to work with so-called barrel files (using an index file in a folder to bundle exports for the consuming code). Barrel files should be used sparsely because as long as ES Modules and/or Webpack tree shaking is not fully supported they could increase bundle sizes. We typically only bundle code that would be used together anyway.
- When writing complex components, we like them to have their own folder with
sub-folders for
logic
andcomponents
that contain code which is only used internally by the component. In the case of logic it can also be a filelogic.ts
if there is not a lot of business logic. The components folder typically uses a barrel file. When a component and sub-components share some local types they are often put in a separatetypes.ts
file to avoid circular dependencies. - When a component uses its own folder it typically has a barrel file exporting
only the public interface. The main component should preferably not live in an
index.tsx file but its own named file that is exported by
index.ts
- Booleans are prefixed with is/has/should etc. However, booleans that are part of component props interfaces are usually not prefixed, to keep them aligned with standard html element syntax.
- Data schema properties and locale keys are all snake_cased. These could be viewed as external data sources / APIs.
- Event props and handlers follow a pattern of
onEventName
vshandleEventName
where theon
part is used for the component props API andhandle
is for the actual function definition. This makes it easy to follow when you want to internally handle an event and at the same time pass it on to a handler on the props. - We prefer to use named function declarations over function expressions, except
for inline lambda functions of course. This means
function doSomething(){}
instead ofconst doSomething = () => {}
- We avoid unnecessary short-hand variable names like
arr
for array ori
for index. There are a few exceptions we use regularly;x
for use inmap
andfilter
functions, andacc
for areduce
accumulator. - All Unix timestamps are defined in seconds, not milliseconds like you would expect in Javascript. This is because our data sources are using seconds.
For developers actively working on the platform we recommend reading the documentation here.