App Built-in Extensions

Built-in extensions are default app extensions that are always installed when you create a Backstage app.

Disable built-in extensions

All built-in extensions can be disabled in the same way as you disable any other extension:

app-config.yaml

extensions:
  # Disabling the built-in app root alert element
  - app-root-element:app/alert-display: false

warning

Be careful when disabling built-in extensions, as there may be other extensions depending on their existence. For example, the built-in "alert display" extension displays messages retrieved via AlertApi and disabling this extension will cause the application to no longer display these messages unless you install another extension that displays messages from AlertApi.

Override built-in extensions

You can override any built-in extension whenever their customizations, whether through configuration or input, do not meet a use case for your Backstage instance. Check out this documentation on how to override application extensions.

warning

Be aware there could be some implementation requirements to properly override an built-in extension, such as using same apis and do not remove inputs or configurations otherwise you can cause a side effect in other parts of the system that expects same minimal behavior.

Default built-in extensions

App

This extension is the first extension attached to the extension tree. It is responsible for receiving the application's root element and other Frontend framework inputs.

Inputs

Name	Description	Type	Optional	Default	Extension creator
root	The app root element.	coreExtensionData.reactElement	false	The App/Root extension output.	No creator available, configure or override the App/Root extension.
apis	The app apis factories.	createApiExtension.factoryDataRef	false	See default apis.	createApiExtension
themes	The app themes list.	createThemeExtension.themeDataRef	false	See default themes.	createThemeExtension
components	The app components list.	createComponentExtension.componentDataRef	false	See default components.	createComponentExtension
translations	The app translations list.	createTranslationExtension.translationDataRef	false	-	createTranslationExtension

Default theme extensions

Extensions that provides default theme inputs for the App extension.

kind	namespace	name	id
theme	app	light	theme:app/light
theme	app	dark	theme:app/dark

Default components extensions

Extensions that provides default components inputs for the App extension.

kind	namespace	name	id
components	app	core.components.progress	components:app/core.components.progress
components	app	core.components.notFoundErrorPage	components:app/core.components.notFoundErrorPage
components	app	core.components.errorBoundaryFallback	components:app/core.components.errorBoundaryFallback

Default apis extensions

Extensions that provides default apis inputs for the App extension.

kind	namespace	name	id
api	core.discovery	-	api:core.discovery
api	core.alert	-	api:core.alert
api	core.analytics	-	api:core.analytics
api	core.error	-	api:core.error
api	core.storage	-	api:core.storage
api	core.fetch	-	api:core.fetch
api	core.oauthrequest	-	api:core.oauthrequest
api	core.auth.google	-	api:core.auth.google
api	core.auth.microsoft	-	api:core.auth.microsoft
api	core.auth.github	-	api:core.auth.github
api	core.auth.okta	-	api:core.auth.okta
api	core.auth.gitlab	-	api:core.auth.gitlab
api	core.auth.onelogin	-	api:core.auth.onelogin
api	core.auth.bitbucket	-	api:core.auth.bitbucket
api	core.auth.bitbucket-server	-	api:core.auth.bitbucket-server
api	core.auth.atlassian	-	api:core.auth.atlassian
api	plugin.permission.api	-	api:plugin.permission.api

App root

This is the extension that creates the app root element, so it renders root level components such as app router and layout.

Inputs

Name	Description	Requirements	Optional	Default	Extension creator
router	A React component that should manager the app routes context.	It must be one router component or a custom component compatible with the 'react-router' library.	true	BrowserRouter	createRouterExtension
signInPage	A React component that should render the app sign-in page.	Should call the onSignInSuccess prop when the user has been successfully authorized, otherwise the user will not be correctly redirected to the application home page.	true	The default AppRoot extension does not use a default component for this input, it bypasses the user authentication check and always renders all routes when a login page is not installed.	createSignInPageExtension
children	A React component that renders the app sidebar and main content in a particular layout.	-	false	The App/Layout extension output.	No creator available, configure or override the App/Layout extension.
elements	React elements to be rendered outside of the app layout, such as shared popups.	-	false	See default elements.	createAppRootElementExtension
wrappers	React components that should wrap the root element.	-	true	-	createAppRootWrapperExtension

Default app root elements extensions

Alert Display

An app root element extension that displays messages posted via the AlertApi.

kind	namespace	name	id
app-root-element	app	alert-display	app-root-element:app/alert-display

Configurations

Key	Type	Default value	Description
transientTimeoutMs	number	5000	Time in milliseconds to wait before displaying messages.
anchorOrigin	{ vertical: 'top' | 'bottom', horizontal: 'left' | 'center' | 'right' }	{ vertical: 'top', horizontal: 'center' }	Position on the screen where the message alert will be displayed.

Override or disable the extension

If you do not want to display alerts, disable this extension or if the available settings do not meet your needs, override this extension.

warning

The built-in "alert display" extension displays messages retrieved via AlertApi and disabling this extension will cause the application to no longer display these messages unless you install another extension that displays messages from AlertApi.

OAuth Request Dialog

An app root element extension that renders the oauth request dialog, it is based on the oauthRequestApi.

kind	namespace	name	id
app-root-element	app	oauth-request-dialog	app-root-element:app/oauth-request-dialog

App layout

Renders the app's sidebar and content in a specific layout.

kind	namespace	name	id
-	app	layout	app/layout

Inputs

Name	Description	Type	Optional	Default	Extension creator
nav	A React element that renders the app sidebar.	coreExtensionData.reactElement	false	-	Override the App/Nav extension.
content	A React element that renders the app content.	coreExtensionData.reactElement	false	-	Override the App/Routes extension.

App nav

Extension responsible for rendering the logo and items in the app's sidebar.

kind	namespace	name	id
-	app	nav	app/nav

Inputs

Name	Description	Type	Optional	Default	Extension creator
logos	A nav logos object.	createNavLogoExtension.logoElementsDataRef	true	-	createNavLogoExtension
items	Nav items target objects.	createNavItemExtension.targetDataRef	true	-	createNavItemExtension

App routes

Renders a route element for each route received as input and a NotFoundErrorPage component.

kind	namespace	name	id
-	app	routes	app/routes

Caveats

Be careful when overriding this extension, as to do so correctly you must consider these implementation requirements:

• The routing system is managed by more than one extension, and they all use react-router behind the scenes. There are also some utilities that are based on the same routing library like useRouteRefParams. Therefore, you cannot use a different library without causing side effects in these other extensions and helper utilities;
• Don't remove configs or inputs, just extend these things yourself with optional new options, otherwise it will cause breaking changes for extensions like createPageExtension that depend on this type of inputs;
• Remember to user the route refs for getting paths dynamically, otherwise if an adopter modifies a path through configuration, the route is not going to point to the configured path;
• Adopters expect to be able to customize the NotFoundErrorPage component via Components API, you should render this component for routes not configured.

Inputs

Name	Description	Type	Optional	Default	Extension creator
routes	The route objects list.	{ path: coreExtensionData.routePath, ref: coreExtensionData.routeRef.optional(), element: coreExtensionData.reactElement }	false	-	createPageExtension