PushSubscription: toJSON() method
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since March 2023.
Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.
Note: This feature is available in Web Workers.
The toJSON() method of the PushSubscription interface returns a JSON-serializable plain object representing the PushSubscription object.
The method is automatically called by JSON.stringify() when a PushSubscription object is encountered during JSON serialization.
Syntax
toJSON()
Parameters
None.
Return value
A JSON-serializable plain object containing the following properties:
endpointexpirationTimekeys: thep256dhandauthvalues returned bygetKey(), encoded as base64url strings without padding
Unless stated otherwise, each property's value is copied as-is.
Examples
Calling toJSON() directly
This example obtains a PushSubscription object. Calling toJSON() directly returns a plain object. Its properties have the same values as the corresponding properties of the original object.
navigator.serviceWorker.ready.then((reg) => {
reg.pushManager.getSubscription().then((subscription) => {
const json = subscription.toJSON();
console.log(json); // A plain object
console.log(typeof json); // "object"
console.log(json.endpoint); // Same value as subscription.endpoint
});
});
Serializing to a JSON string
Within the getSubscription() callback from the previous example, the same object can be serialized using JSON.stringify(), which calls the toJSON() method automatically.
console.log(JSON.stringify(subscription));
This would log a JSON string like so (formatted for readability):
{
"endpoint": "https://push.example.com/subscriptions/12345",
"expirationTime": null,
"keys": {
"p256dh": "...",
"auth": "..."
}
}
The base64url-encoded key values are abbreviated as "..." for readability.
Specifications
| Specification |
|---|
| Push API # dom-pushsubscription-tojson |