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OldestClientObserver Class

The OldestClientObserver is a utility inspect if the local client is the oldest amongst connected clients (in terms of when they connected) and watch for changes.

It is still experimental and under development. Please do try it out, but expect breaking changes in the future.

This API is provided for existing users, but is not recommended for new users.

To use, import via @fluid-experimental/oldest-client-observer/legacy.

For more information about our API support guarantees, see here.

Signature​

export declare class OldestClientObserver extends TypedEventEmitter<IOldestClientObserverEvents> implements IOldestClientObserver

Extends: TypedEventEmitter<IOldestClientObserverEvents>

Implements: IOldestClientObserver

Remarks​

### Creation

The OldestClientObserver constructor takes an IOldestClientObservable. This is most easily satisfied with either an IContainerRuntime or an IFluidDataStoreRuntime:

// E.g. from within a BaseContainerRuntimeFactory:
protected async containerHasInitialized(runtime: IContainerRuntime) {
    const oldestClientObserver = new OldestClientObserver(runtime);
    // ...
}
// From within a DataObject
protected async hasInitialized() {
    const oldestClientObserver = new OldestClientObserver(this.runtime);
    // ...
}

### Usage

To check if the local client is the oldest, use the isOldest() method.

if (oldestClientObserver.isOldest()) {
    console.log("I'm the oldest");
} else {
    console.log("Someone else is older");
}

### Eventing

OldestClientObserver is an EventEmitter, and will emit events when the local client becomes the oldest and when it is no longer the oldest.

oldestClientObserver.on("becameOldest", () => {
    console.log("I'm the oldest now");
});
oldestClientObserver.on("lostOldest", () => {
    console.log("I'm not the oldest anymore");
});

Constructors​

Constructor Alerts Description
(constructor)(observable) Alpha Constructs a new instance of the OldestClientObserver class

Constructor Details​

(constructor)​

Constructs a new instance of the OldestClientObserver class

This API is provided as an alpha preview and may change without notice.

To use, import via @fluid-experimental/oldest-client-observer/alpha.

For more information about our API support guarantees, see here.

Signature​

constructor(observable: IOldestClientObservable);

Parameters​

Parameter Type Description
observable IOldestClientObservable