What is Glue42 Core?

Core Concepts

Glue42 Client


We call a "Glue42 Client" every application which initializes the @glue42/web library and thus connects to the Glue42 Core Environment. On a single domain there could be one or more Glue42 Clients connected to the same Glue42 Core Environment, which gives them full access to the interop, window and contexts functionality offered by the platform.

A Glue42 Client can be any JS application written using Vanilla JS, React, Angular or any other framework.

Initializing a Glue42 Client

To "initialize" a client, means to connect to the Glue42 Core Environment using the @glue42/web library. We have prepared a more detailed guides on how do that using:

We are not going to overlap the explanations there, instead we will get in-depth on how we can configure this initialization and why would we want to do that. Regardless of whether you use Vanilla JS or our React library, the configuration is done using two optional elements, and we will cover both here:


Regardless of whether you use the @glue42/web library directly or our React library, the initialization is done by invoking a factory function exposed by the libraries. This factory function accepts an optional configuration object of type Glue42Web.Config. Full details on the Glue42 Web API can be found at the API reference page, however here we will explain the config object in more details.

The interface of Glue42Web.Config looks like this:

interface Glue42Web.Config {
    worker?: string;
    layouts?: {
        autoRestore?: boolean;
        autoSaveWindowContext?: boolean;
    extends?: string | false;

The extends property can be used to disable fetching glue.config.json (by setting it to false) or to set a location of the file, different from the default (/glue/glue.config.json). This is advisable when you decide not to use a glue.config.json.

Note that if you set a different location for glue.config.json, then you need to make sure that the worker.js (Glue42 Core Environment) is located next to the config. Note that if you set extends to false, then by default all clients will try to connect to the worker at /glue/worker.js. You need to set the worker property, if you want to overwrite the default.

The layouts property enables or disables auto-saving/restoring of windows' location and context on close.


We have covered the glue.config.json in the Glue42 Core Environment section where we explained all of it's properties. We have also explained how you can use this config to extend parts of the Glue42 Core Environment in the Single Application setup guide.

Right now we are interested in what can this config object do to help the Glue42 Clients. The interface of glue.config.json is:

interface Glue42CoreConfig {
    glue?: Glue42Web.Config;
    gateway?: GatewayConfig;

We are interested in the glue property, which is of type Glue42Web.Config. The Glue42Web.Config defined in property glue will be used (unless explicitly told not to) by all clients on the domain as a base config. This base config can be extended by each client and is helpful so that you don't have to declare the same object in all of your clients.


// glue.config.json
    "glue": {
        "layouts": {
            "autoRestore": true,
            "autoSaveWindowContext": true

Glue42Web.Config Without any further configuration all Glue42 Clients will now auto-restore and auto-save their window contexts by default. If you wish a specific client to ignore this default, you can either: