TypeScript and Chrome Notification

A couple of options here:

1. Add the following line to the top of your file.

   declare var Notification: any;

   This will make the transpiler pass but won't give you the much of TypeScript's features.

2. Download the definition type (chrome.d.ts).

   TSD seems to be the most popular definition manager.
   Typings is another promising alternative.

A generic typing file is available via this GitHub TypeScript issue;

Create a new typing definition file called notification.d.ts and add the following code.

type NotificationPermission = "default" | "denied" | "granted";

type NotificationDirection = "auto" | "ltr" | "rtl";

interface NotificationPermissionCallback {
    (permission: NotificationPermission): void;
}

interface NotificationOptions {
    dir?: NotificationDirection;
    lang?: string;
    body?: string;
    tag?: string;
    image?: string;
    icon?: string;
    badge?: string;
    sound?: string;
    vibrate?: number | number[],
    timestamp?: number,
    renotify?: boolean;
    silent?: boolean;
    requireInteraction?: boolean;
    data?: any;
    actions?: NotificationAction[]
}

interface NotificationAction {
    action: string;
    title: string;
    icon?: string;
}

declare class Notification extends EventTarget {
    constructor(title: string, options?: NotificationOptions);

    static readonly permission: NotificationPermission;
    static requestPermission(): Promise<NotificationPermission>;
    static requestPermission(deprecatedCallback: (permission: NotificationPermission) => void): void;

    static readonly maxActions: number;

    onclick: EventListenerOrEventListenerObject;
    onerror: EventListenerOrEventListenerObject;

    close(): void;

    readonly title: string;
    readonly dir: NotificationDirection;
    readonly lang: string;
    readonly body: string;
    readonly tag: string;
    readonly image: string;
    readonly icon: string;
    readonly badge: string;
    readonly sound: string;
    readonly vibrate: number[];
    readonly timestamp: number;
    readonly renotify: boolean;
    readonly silent: boolean;
    readonly requireInteraction: boolean;
    readonly data: any;
    readonly actions: NotificationAction[]
}

Making sure the typings file is included in your project (tsconfig.json);

    "typeRoots": [
        "typings/notification.d.ts"
    ]

You should now be able to access Notification.