The Reservoir Design System (DS) is NYPL’s open-source extensible React library for products and experiences with the accessibility as its foundation. It ships functional, stateless components with consistent NYPL styling. You can learn more about the project and its goals on the project's wiki.

Note: This library is still in beta. Until we release the stable 1.0.0 version, we are loosely using semantic versioning.

Storybook documentation

• Production - deployed to Github Pages
• Development - deployed to Tugboat QA

Follow these steps to setup a local installation of the project:

1. Clone the repo

$ git clone https://github.com/NYPL/nypl-design-system.git

2. Install all the dependencies

$ npm install

3. Run the Storybook instance and view it at http://localhost:6006

$ npm run storybook

You can now edit styles or templates in the src directory, and they will automatically re-build and update in the Storybook instance. Adding new stories or changing story names will require a page refresh.

Information about active maintainers, how we run reviews, and more can be found in our wiki page for Contributing to the Design System.

Follow the contribution document to follow git branching convetions, component creation and update guidelines, testing methodoly, and documentation guidelines.

We recommend using Node version 12.22.x since the DS has some issues with versions higher than 12.x. The Github Actions for linting, automated testing, deploying to Github Pages, and releasing to npm are all running on Node 12.x.

If you are using nvm, the local .nvmrc file can be use to set your local Node version with the nvm use command (will be set to 12.22.x).

To develop with a local version of the Design System:

1. In the Design System directory, run:

$ npm link

2. Go to the consuming application directory and run:

$ npm link @nypl/design-system-react-components

3. Go back to the Design System directory and run the following command. It allos the local Design System to be rebuilt and exported automatically:

$ npm start

It's possible when running npm link that you'll get an Invalid Hook issue. If this occurs, it's most likely caused by having two versions of React when trying to run the application while the NYPL DS package is linked. This Duplicate React issue is covered by the React team.

To be more specific, you should run the following in your local DS directory, where [../path/to/application] is the local directory of the consuming application.

$ npm link [../path/to/application]/node_modules/react

Now you should be able to run npm start in the DS directory and npm run dev (or whatever your application uses) in the application directory and not get an Invalid Hook error.

To unlink the DS codebase:

1. Run npm unlink in the Design System directory.
2. Run npm unlink --no-save @nypl/design-system-react-components in the consuming application.

To use the Design System in your project:

1. Install the DS:

$ npm install @nypl/design-system-react-components

2. Import the styles in your main css file

@import "~@nypl/design-system-react-components/dist/styles.css";

3. Import the DSProvider component

In order to use DS components in a consuming application, there is a necessary step that must be done for component styles to properly render. Consuming applications need to wrap all the DS components with a simple provider component. Fortunately, this only needs to be done once at the top level of the consuming application.

Once the following is completed, DS components that internally use Chakra UI will render styles properly.

// your main application file
import { DSProvider } from "@nypl/design-system-react-components";

// ...
const ApplicationContainer = (props) => {
  // ...
  return (
    <DSProvider>
      <div className="my-app">
        // ...
        {children}
      </div>
    </DSProvider>
  );
};

4. Use DS components!

Consult Storybook for the list of available components and props that they require.

Here's an example with the Link component:

import { Link } from "@nypl/design-system-react-components";

function NewComponent(props) {
  return <Link href="https://www.hathitrust.org/">HathiTrust</Link>;
}

Sometimes you may have conflicts, perhaps with React-Router. In that case, you can alias your imports:

import * as DS from "@nypl/design-system-react-components";
import { Link } from "react-router";

function NewComponent(props) {
  return (
    <DS.Link>
      <Link to="/license">public domain</Link>
    </DS.Link>
  );
}

<body>
  <NYPLHeader />

  <div class="app">
    <!-- your code here -->
  </div>

  <NYPLFooter />
</body>

The Chakra UI component library has been integrated into the Reservoir Design System. We are still progressing towards using Chakra components and patterns to build DS components, and therefore documentation and features are expected to change. While the implementation details of DS components will use Chakra, the DS package itself will export some Chakra components.

The list of re-exported Chakra components can be found in the main index.ts file. They include:

• Box, Center, Circle, Grid, GridItem, HStack, Square, Stack, VStack

Find more information about the Design System's internal use of Chakra to create and refactor components in the Storybook documentation page. The following two links have the same information but in different formats for your reading preference:

• MDX format
• Storybook page

Chakra was integrated into the Design System in version 0.25.0. For those looking to update to a version greater than or equal 0.25.0, check out our Chakra Migration Guide.

You can also use the Design System styles in your project through the unpkg CDN:

<link href="https://unpkg.com/@nypl/design-system-react-components/dist/styles.css">

If you need to reference a particular version you can do do by including the version number in the URL:

<link href="https://unpkg.com/@nypl/design-system-react-components@0.9.1/dist/styles.css">

You can check out a working Codepen with unpkg here.

The Reservoir Design System leverages Storybook to document all the React components and style guidelines. The Storybook documentation can be found here. For your convenience, the Reservoir Design System components have been organized into logical categories based on both form and function. Please refer to the COMPONENTS section in the Storybook sidebar.

There are currently two main instances of the Reservoir Design System Storybook documentation. There are also "preview" sites that are used to quickly and easily view pull request changes.

Production

The production Storybook documentation is deployed to Github Pages. This is the main instance we use to share the latest stable release of the Reservoir Design System. This documentation site is deployed through Github Actions only on merges to the release branch.

As of July, 2021, the Github Pages production site gets deployed every two weeks on the same schedule as npm releases.

Development

The development Storybook documentation is deployed to Tugboat QA. This development site has all the working updates that get merged to the development branch. This means that this site is constantly being updated as pull requests are being merged in. This site is used to see the lastest changes during a working sprint before a production release is made.

Preview Sites

Preview Storybook documentation sites are deployed to Tugboat QA for every pull request. They follow a pattern such as pr[number]-[hash].tugboat.qa where [number] is the number of the pull request it is deploying. For example, for pull request #101, Tugboat will deploy a "preview" site to pr101-wldudndlk24kas42.tugboat.qa. Since these "preview" sites are brought up only for pull requests, this means that the URL varies and that those instances are eventually shut off. They are not meant to be used as long-term sites but rather for reviewing working changes within the team.

When actively developing components or fixing bugs, make sure that the related stories are created or updated. This means updating the respective [component-name].stories.mdx file. For information on how to write stories, check out the Anatomy of a Story wiki page.

For stand-alone document pages in Storybook, you need to:

1. create the [page-name].stories.mdx file in src/docs/
2. add the file reference to the .storybook/main.js file in the stories array

To help consuming application developers understand which version of the DS is required for a specific component, each component story page includes the following:

• when a component was added to the DS
• minimum version of the DS required for the latest version of a component

Example Component Version Table

There should be no need to run the static Storybook instance while actively developing -- it's used exclusively for building out the gh-pages environment and deploying it to Github Pages. In the event that you do run the static Storybook npm script, run:

$ npm run build-storybook

You can then view /storybook-static/index.html in your browser. Make sure not to commit this directory.

The Reservoir Design System is built with Typescript. Check out the Design System's Typescript documentation for more information on why we chose to build React components in Typescript and the benefits and the gotchas we encountered.

The Reservoir Design System runs unit tests with Jest and React Testing Library.

To run all tests once:

$ npm test

If you're actively writing or updating tests, you can run the tests in watch mode. This will wait for any changes and run when a file is saved:

$ npm run test:watch

If you want to run tests on only one specific file, run:

$ npm test -- src/[path/to/file]

For example, to test the Link component, run:

$ npm test -- src/components/Link/Link.test.tsx

The NYPL DS implements snapshot testing with react-test-renderer and jest. Using React Testing Library to test our components works well to make sure that what the user sees is what the component should be rendering. There are also some behavioral tests that test user interactions. If, however, a component's DOM or SCSS styling was unintentionally updated, we can catch those bugs through snapshot testing.

The react-test-renderer package, will create a directory and a file to hold .snap files after a unit test is created. Using the Notification component as an example, this is the basic layout for a snapshot test:

import renderer from "react-test-renderer";

// ...

it("Renders the UI snapshot correctly", () => {
  const tree = renderer
    .create(
      <Notification
        id="notificationID"
        notificationHeading="Notification Heading"
        notificationContent={<>Notification content.</>}
      />
    )
    .toJSON();
  expect(tree).toMatchSnapshot();
});

If this is a new test and we run npm test, a /__snapshots__/Notification.test.tsx.snap file is created. This holds the DOM structure as well as any inline CSS that was added.

exports[`Notification Snapshot Renders the UI snapshot correctly 1`] = `
<aside
  className="notification notification--standard "
  id="notificationID"
>
  // Removed for brevity...
</aside>
`;

Now, if we unintentionally update the Notification.tsx component to render a div instead of an aside element, this test will fail.

If you want to update any existing snapshots, re-run the test script as:

$ npm test -- --updateSnapshot

Each snapshot file also includes a link to its Jest Snapshot documentation which is recommended to read!

Through the @storybook/addon-jest plugin, we can see a component's suite of unit tests right Storybook. In the "Addons" panel, a "Test" tab will display all the tests for the current component and whether they pass or fail.

After writing new tests, run npm run test:generate-output to create a new JSON file that is used by Storybook. This JSON file contains all the test suites for all the components and Storybook picks this up and automatically combines a component with its relevant unit tests. Make sure to commit this file although new builds on Github Pages will recreate this file for the production Storybook instance.

The Reservoir Design System is built with accessibility in mind. By using Chakra UI as our foundational base, the custom DS components built with Chakra have accessibility concerns already implemented. On top of built-in accessible elements, DS components internally work to link labels with input elements, to add correct aria-* attributes, to visually hide text but still associate it with the correct element for titles and descriptions, to auto-generate a random id attribute if none was passed, and much more.

We make use of:

• eslint-plugin-jsx-a11y for finding accessibility errors through linting and through IDE environments.
• jest-axe for running axe-core on every component's unit test file. This is part of the automated tests that run in Github Actions through the npm test command.
• @storybook/addon-a11y for real-time accessibility testing in the browser through Storybook. Every component has a tab that displays violations, passes, and incomplete checks performed by axe-core.

If applicable, DS components have section(s) on accessibility in their Storybook documentation. For example, in the Slider's Storybook file, there are two "Accessibility" sections for each of the two Slider types, "single" and "range". This gives an explanation on additional changes we made to make the combination of elements in the Slider component accessible.

The Reservoir Design System provides accessible stories, but real live data can necessitate additional accessibility requirements beyond what we're committed to in our generic, extensible components. To ensure your products' final result is accessible, please adhere to the accessibility requirements put together by NYPL's accessibility coordinator on Metronome.

NYPL's Metronome instance is currently password protected. For access to Metronome, please contact NYPL's UX team or Design System team.

You can also use the Design System styles in your project through the unpkg CDN:

<link href="https://unpkg.com/@nypl/design-system-react-components/dist/styles.css">

If you need to reference a particular version you can do do by including the version number in the URL:

<link href="https://unpkg.com/@nypl/design-system-react-components@0.9.1/dist/styles.css">

You can check out a working Codepen with unpkg here.