Kepler.gl is a data-agnostic, high-performance web-based application for visual exploration of large-scale geolocation data sets. Built on top of deck.gl, kepler.gl can render millions of points representing thousands of trips and perform spatial aggregations on the fly.

For what it is capable of, take a look at kepler.gl demo app.

Kepler.gl is a redux component that uses redux reducer to store and manage state transitions. This package consists of a reducer and the UI components to render and customize the map.

For information on how to embed kepler.gl in your app take a look at this tutorial on vis.academy.

Links

• Website
• Demo
• Examples
• App User guide
• Tutorial
• Stack Overflow
• Contribution Guidelines
• API Docs - Coming Soon

Env

Use Node v6 and above, older node versions have not been tested

For best results, use nvm nvm install.

Install kepler.gl

Install node (> 6), yarn, and project dependencies

npm install --save kepler.gl
// or
yarn add kepler.gl

kepler.gl is built upon mapbox. You will need a Mapbox Access Token to use it.

Develop kepler.gl

Take a look at the development guide to develop kepler.gl locally.

Basic Usage

Here are the basic steps to import kepler.gl into your app. You also take a look at the examples folder. Each example in the folder can be installed and run locally.

1. Mount kepler.gl reducer in your app reducer.

Kepler.gl uses Redux to manage its internal state, along with react-palm middleware to handle side effects.

You need to add taskMiddleware to your store too. We are actively working on a solution where react-palm will not be required, however it is still a very nice side effects management tool that works easier for testing than react-thunk.

import keplerGlReducer from 'kepler.gl/reducers';
import {createStore, combineReducers, applyMiddleware, compose} from 'redux';
import {taskMiddleware} from 'react-palm/tasks';

const reducers = combineReducers({
  // <-- mount kepler.gl reducer in your app
  keplerGl: keplerGlReducer,

  // Your other reducers here
  app: appReducer
});

// using createStore
const store = createStore(reducer, applyMiddleware(taskMiddleware))

// using enhancers
const initialState = {}
const middlewares = [taskMiddleware]
const enhancers = [
  applyMiddleware(...middlewares)
]

const store = createStore(reducer, initialState, compose(...enhancers))

If you mount kepler.gl reducer in another address instead of keplerGl, or the kepler.gl reducer is not mounted at root of your state, you will need to specify the path to it when you mount the component with the getState prop.

2. Mount kepler.gl Component

import KeplerGl from 'kepler.gl';

const Map = props => (
  <KeplerGl
      id="foo"
      width={width}
      mapboxApiAccessToken={token}
      height={height}/>
);

Component Props

id (String, required)

• Default: map

The id of this KeplerGl instance. id is required if you have multiple KeplerGl instances in your app. It defines the prop name of the KeplerGl state that is stored in the KeplerGl reducer. For example, the state of the KeplerGl component with id foo is stored in state.keplerGl.foo.

In case you create multiple kepler.gl instances using the same id, the kepler.gl state defined by the entry will be overridden by the latest instance and reset to a blank state.

mapboxApiAccessToken (String, required)

• Default: undefined

You can create a free account at mapbox and create a token at www.mapbox.com/account/access-tokens

getState (Function, optional)

• Default: state => state.keplerGl

The path to the root keplerGl state in your reducer.

width (Number, optional)

• Default: 800

Width of the KeplerGl UI.

height (Number, optional)

• Default: 800

appName (String, optional)

• Default: Kepler.Gl

App name displayed in side panel header

version (String, optional)

• Default: v1.0

version displayed in side panel header

onSaveMap (Function, optional)

• Default: () => {}

Action called when click Save Map Url in side panel header.

actions (Object, optional)

• Default: {}

Actions payload creator to replace default kepler.gl action. Only use custom action when you want to modify action payload.

mint (Boolean, optional)

• Default: true

Whether to load a fresh empty state when component is mounted. when parse mint: true kepler.gl component will always load a fresh state when re-mount the same component, state inside this component will be destroyed once its unmounted. By Parsing mint: false kepler.gl will keep the component state in the store even when it is unmounted, and use it as initial state when re-mounted again. This is useful when mounting kepler.gl in a modal, and keep the same map when re-open.

3. Dispatch custom actions to keplerGl reducer.

One advantage of using the reducer over React component state to handle keplerGl state is the flexibility to customize its behavior. If you only have one KeplerGl instance in your app or never intend to dispatch actions to KeplerGl from outside the component itself, you don’t need to worry about forwarding dispatch and can move on to the next section. But life is full of customizations, and we want to make yours as enjoyable as possible.

There are multiple ways to dispatch actions to a specific KeplerGl instance.

• In the root reducer, with reducer updaters.

Each action is mapped to a reducer updater in kepler.gl. You can import the reducer updater corresponding to a specific action, and call it with the previous state and action payload to get the updated state. e.g. updateVisDataUpdater is the updater for ActionTypes.UPDATE_VIS_DATA (take a look at each reducer reducers/vis-state.js for action to updater mapping). Here is an example how you can listen to an app action QUERY_SUCCESS and call updateVisDataUpdater to load data into Kepler.Gl.

import keplerGlReducer, {visStateUpdaters} from 'kepler.gl/reducers';

// Root Reducer
const reducers = combineReducers({
 keplerGl: keplerGlReducer,

 app: appReducer
});

const composedReducer = (state, action) => {
 switch (action.type) {
   case 'QUERY_SUCCESS':
     return {
       ...state,
       keplerGl: {
         ...state.keplerGl,

         // 'map' is the id of the keplerGl instance
         map: {
            ...state.keplerGl.map,
            visState: visStateUpdaters.updateVisDataUpdater(
              state.keplerGl.map.visState, {datasets: action.payload})
         }
       }
     };
 }
 return reducers(state, action);
};

export default composedReducer;

• Using redux connect

You can add a dispatch function to your component that dispatches actions to a specific keplerGl component, using connect.

// component
import KeplerGl from 'kepler.gl';

// action and forward dispatcher
import {toggleFullScreen, forwardTo} from 'kepler.gl/actions';
import {connect} from 'react-redux';

const MapContainer = props => (
  <div>
    <button onClick={() => props.keplerGlDispatch(toggleFullScreen())}/>
    <KeplerGl
      id="foo"
    />
  </div>
)

const mapStateToProps = state => state
const mapDispatchToProps = (dispatch, props) => ({
 dispatch,
 keplerGlDispatch: forwardTo(‘foo’, dispatch)
});

export default connect(
 mapStateToProps,
 mapDispatchToProps
)(MapContainer);

• Wrap action payload

You can also simply wrap an action into a forward action with the wrapTo helper

// component
import KeplerGl from 'kepler.gl';

// action and forward dispatcher
import {toggleFullScreen, wrapTo} from 'kepler.gl/actions';

// create a function to wrapper action payload to 'foo'
const wrapToMap = wrapTo('foo');
const MapContainer = ({dispatch}) => (
  <div>
    <button onClick={() => dispatch(wrapToMap(toggleFullScreen())} />
    <KeplerGl
      id="foo"
    />
  </div>
);

4. Replace default components.

Everyone wants the flexibility to render custom kepler.gl componenents. Kepler.gl has a dependency injection system that allow you to inject components to KeplerGl replacing existing ones. All you need to do is to create a component factory for the one you want to replace, import the original component factory and call injectComponents at the root component of your app where KeplerGl is mounted. Take a look at examples/demo-app/src/app.js and see how it renders a custom side panel header in kepler.gl

import {injectComponents, PanelHeaderFactory} from 'kepler.gl/components';

// define custom header
const CustomHeader = () => (<div>My kepler.gl app</div>);
const myCustomHeaderFactory = () => CustomHeader;

// Inject custom header into Kepler.gl, replacing default
const KeplerGl = injectComponents([
  [PanelHeaderFactory, myCustomHeaderFactory]
]);

// render KeplerGl, it will render your custom header instead of the default
const MapContainer = () => (
  <div>
    <KeplerGl
      id="foo"
    />
  </div>
);

Using withState helper to add reducer state and actions to customized component as additional props.

import {withState, injectComponents, PanelHeaderFactory} from 'kepler.gl/components';
import {visStateLens} from 'kepler.gl/reducers';

// custom action wrap to mounted instance
const addTodo = (text) => wrapTo('map', {
    type: 'ADD_TODO',
    text
});

// define custom header
const CustomHeader = ({visState, addTodo}) => (
  <div onClick={() => addTodo('hello')}>{`${Object.keys(visState.datasets).length} dataset loaded`}</div>
);

// now CustomHeader will receive `visState` and `addTodo` as additional props.
const myCustomHeaderFactory = () => withState(
  // keplerGl state lenses
  [visStateLens],
  // customMapStateToProps
  headerStateToProps,
  // actions
  {addTodo}
)(CustomHeader);

5. How to add data to map

In order to interact with a kepler.gl instance and add new data to it the following methods are available:

• updateVisData
• addDataToMap It is also important to remember that Kepler.gl provides an easy API (KeplerGlSchema.getConfigToSave) to generate a dump of the current kepler instance configuration.

addDataToMap

This method is similar to UpdateVisData but it is able to update the full kepler.gl configuration (mapState, mapStyle, visState). This action takes an object as input with the following properties:

{
    datasets | object: same as UpdateVisData
    options | object: same as UpdateVisData
    config | object: this object will contain the full kepler.gl instance configuration {mapState, mapStyle, visState}.
}

config: {
  mapState: {
    latitude: 33.88608913680742,
    longitude: -84.43459130456425
  }
}

the latter will be applied and the map view will be moved the defined coordinates.