Highcharts TypeScript Declarations (beta)

Highcharts TypeScript Declarations (beta)#

Highcharts 7 is the first release with integrated support for TypeScript through declarations files. TypeScript-compatible editors can give you tooltips and suggestions for Highcharts as you type. The TypeScript compiler watches and points out potential problems while coding. The outcome is a faster and better fail-proofed development cycle for your Highcharts-based solutions.

Summary of Changes from v7.2.1 to v8.0.0#

With Highcharts v8 the file size of TypeScript declarations has been reduced by 40 percent. This has been achieved by combining individual options to more generic shared options. Following are the most significant changes:

Name Scheme in v7.2.1	Name Scheme in v8.0.0
`AccessibilityAnnounceNewDataOptions`	`AccessibilityAnnounceNewDataOptionsObject`
`DataLabelsFilterOperatorValue`	`OptionsOperatorValue`
`ExportingButtonsContextButtonOptions`	`ExportingButtonsOptionsObject`
`NavigatorSeriesDataGroupingOptions`	`DataGroupingOptionsObject`
`PlotLineAccessibilityOptions`¹	`SeriesAccessibilityOptionsObject`
`PlotLineAnimationOptions`¹	`AnimationOptionsObject`
`PlotLineConnectorsOptions`¹	`SeriesConnectorsOptionsObject`
`PlotLineDataGroupingOptions`¹	`DataGroupingOptionsObject`
`PlotLineEventsOptions`¹	`SeriesEventsOptionsObject`
`PlotLineLabelOptions`¹	`SeriesLabelOptionsObject`
`PlotLineMarkerOptions`¹	`PointMarkerOptionsObject`
`PlotLinePointOptions`¹	`PlotSeriesPointOptions`
`PlotLineStatesOptions`¹	`SeriesStatesOptionsObject`
`PlotLineTooltipOptions`¹	`SeriesTooltipOptionsObject`
`PlotLineZonesOptions`¹	`SeriesZonesOptionsObject`
`SeriesLineDataOptions`²	`PointOptionsObject`
`XAxisAccessibilityOptions`³	`AxisAccessibilityOptionsObject`
`XAxisCrosshairOptions`³	`AxisCrosshairOptions`
`XAxisCurrentDateIndicatorOptions`³	`AxisCurrentDateIndicatorOptions`
`XAxisDateTimeLabelFormatsOptions`³	`AxisDateTimeLabelFormatsOptions`
`XAxisMarkerOptions`³	`PointMarkerOptionsObject`

1) Example, other series options like PlotColumn… are similar affected. 2) Example, other series options like SeriesColumn… are similar affected. 3) Example, other axis options like ColorAxis… are similar affected.

Installation#

You need a TypeScript-capable Editor, like Microsoft's Visual Studio Code, for getting autocompletion and hints for Highcharts. Please note that Highcharts contains comprehensive declarations, which makes increased memory usage in a few editors like Webstorm necessary.

Configuration#

TypeScript#

Highcharts is a charting library most often used in the web browser and in that case you probably need to modify the TypeScript configuration for the target platform. The tsconfig.json below, covers a typical use case of Highcharts:

{
    "compilerOptions": {
        "strict": true,
        "target": "es5",
        "module": "amd",
        "moduleResolution": "node",
        "outDir": "mychart/",
    },
    "exclude": [
        "node_modules"
    ]
}

If you place your TypeScript source code (*.ts) in one of your project folders, the TypeScript compiler will automatically find it, compile it and output the JavaScript compiled code (*.js) to the outDir folder. With the exclude property you prevent specified folders from compiling to TypeScript, for example files found in the node_modules folder.

RequireJS#

Not every web browser is capable to load ES6 modules. Here comes RequireJS into action, but needs some configuration to support the Highcharts package:

require.config({
    packages: [{
        name: 'highcharts',
        main: 'highcharts'
    }],
    paths: {
        'highcharts': 'https://code.highcharts.com'
    }
})

For Highcharts Stock and other additions it is recommended to use the previous configuration and load the module (highcharts/modules/stock) instead. For the package you have to change the configuration in the following way:

require.config({
    packages: [{
        name: 'highcharts',
        main: 'highstock'
    }],
    paths: {
        'highcharts': 'https://code.highcharts.com/stock'
    }
})

Details about the configuration options can be found in the RequireJS documentation.

Migration#

Migration from Definitely Typed#

If you previously used TypeScript declarations for Highcharts like @types/highcharts, you should uninstall them to prevent any mismatch:

npm uninstall @types/highcharts

Migration from JavaScript#

For full fail-proofed development you may convert your project's source code to TypeScript. The initial step is:

npm install typescript && npx tsc --init

More information about migrating JavaScript projects to TypeScript can be found in the official TypeScript handbook.

Solving Problems#

Debugging#

If TypeScript is complaining about your Highcharts options, then it might not find the correct series as a reference. If that is the case, cast the series options explicitly to the desired type and you get more helpful error messages:

series: [{
    type: "line",
    data: [1, 2, "3", 4, 5] as Highcharts.SeriesLineDataOptions
}]

Missing Modules#

Sometimes there isn't a TypeScript declaration for a Highcharts module available. Then cast the module and unknown functions to the any type. Create first a global.d.ts file in your root folder with the following file content:

declare module '*';

After that, you can use all JavaScript modules and cast the Highcharts namespace as required. For example:

import * as Highcharts from 'highcharts';
// Module with declaration:
import AccessibilityModule from 'highcharts/modules/accessibility';
// Module with any type:
import NewModule from 'highcharts/modules/new';
// Initiate the chart
(Highcharts as any).newChart('container', {
    series: [{
        type: 'new',
        data: [1, 2, 3, 4, 5]
    }]
});

Reporting Bugs#

The TypeScript declarations for Highcharts are in a beta state. They can be used in production, but we can't guarantee your code from breaking with future type updates. In that case, probably small modifications to the types will be necessary. If you found something in TypeScript that is not working as in our documentation or demos, you can create an issue report to inform us.

Extending Highcharts in TypeScript#

The Highcharts libraries come with a huge amount of possibilities right out of the box, but for a special use case you might need to extend default behavior of Highcharts. Extending Highcharts in TypeScript follows a straightforward pattern as illustrated with the below example.

Steps#

Set proper types for your extensions
Declare additional interfaces with your extensions to the Highcharts namespace
Make use of existing Highcharts types and interfaces
For a deep dive into TypeScript declaration take a look at the official TypeScript guide.

Example#

If you like to have a custom highlight function for you data points, you could come up with the following code. You might notice, that the beginning code is actually not real TypeScript and instead is just common ECMAScript, widely known as JavaScript:

import * as Highcharts from 'highcharts';
Highcharts.Point.prototype.highlight = function (event) {
    event = this.series.chart.pointer.normalize(event);
    this.onMouseOver(event);
    this.series.chart.tooltip.refresh(this);
    this.series.chart.xAxis[0].drawCrosshair(event, this);
};

First you have to make TypeScript aware of the types in your function, so you have to specify the type of the event parameter in this example:

// ...
Highcharts.Point.prototype.highlight = function (
    event: Highcharts.PointerEvent
): void {
// ...

Secondly assure TypeScript, that creating a new function on Highcharts.Point is really made by intention. You can do this with declarations for the Highcharts namespace - in a separate file like ./global.d.ts or directly in your code:

// ...
declare module 'highcharts/highcharts' {
    interface Point {
        highlight (event: Highcharts.PointerEventObject): void;
    }
}
// ...

Finally the source code of the example would look like this:

import * as Highcharts from 'highcharts';
declare module 'highcharts/highcharts' {
    interface Point {
        highlight (event: Highcharts.PointerEventObject): void;
    }
}
Highcharts.Point.prototype.highlight = function (
    event: Highcharts.PointerEvent
): void {
    event = this.series.chart.pointer.normalize(event);
    this.onMouseOver(event);
    this.series.chart.tooltip.refresh(this);
    this.series.chart.xAxis[0].drawCrosshair(event, this);
};