extensions

Extensions allow Bolt to expose interfaces (endpoints) without providing their implementations; instead, Bolt delegates their implementations to installed apps.

extensions is simply an object in which each key/field specifies a Bolt endpoint and the corresponding value specifies an endpoint exposed by the app's server that is to be called whenever a user navigates to the Bolt endpoint specified in the afore-mentioned key/field.

An example to make things clearer.

The notes app exposes the endpoint:GET: /notes while Bolt exposes the endpointGET: /home. So, you could have your extensions look like this:

"extensions": {
    "/home": "/notes"
}

After this app is installed, if the user navigates to localhost:400/home, your app will automatically be started (let's say on port 500), and the user will automatically be redirected to localhost:500/notes. If you think about it, extensions are a really cool feature of Bolt. You can have as many key-value pairs in your extensions object.

Default Extensions

More than one app can specify the same Bolt endpoint in their extensions. For instance, another installed app could have:

"extensions": {
    "/home": "/my/own/end/point?source=bolt"
}

Bolt allows end users to specify the default extension for a Bolt endpoint. Likewise, with the user's permission, you can set your extension as the default. More on this later.

Types of Extensions

There are 4 types of extensions your app can provide:

1. Views
2. Data
3. Actions
4. Files

Only views are currently supported.

A Little Tip for You

One day Bolt may allow apps to specify external endpoints (endpoints defined on actual web services/websites) in extensions.