Getting Started with the Looker Extension Framework

New in Looker 7.12 is the Looker extension framework.

The Looker extension framework is a development framework that significantly reduces the effort and complexity of building custom JavaScript data applications and tools, such as:

Internal platform applications for your company
External platforms for your customers, such as customer portals for Powered By Looker (PBL) applications built off Looker data
Targeted internal tools
Applications to embed in external applications

Custom applications and tools created with the extension framework can be accessed from within Looker, allowing Looker to handle functions such as authentication, access control and permission management, and API access. This also lets you leverage other common developer resources, such as third-party API endpoints, within Looker.

Extension framework features

The Looker extension framework includes the following features:

The Javascript SDK, which you can use to provide Looker public API access.
Looker components, a library of pre-built TypeScript UI components you can use in your extensions.
The embed SDK, a library of functions you can use to embed dashboards, Looks, and Explores in your extension. See the kitchen sink extension for example code. You can also use the embed SDK to embed your extension into third-party applications by adding the prefix /embed to your extension URL.
The ability to access third-party API endpoints and add third-party data to your extension, or to use external development services:

See the kitchen sink extension for an example of a Looker extension.
The ability to create full screen extensions within Looker:

Full screen extensions can be used for internal or external platform applications. You can use Looker’s existing authentication options for sign-in (such as password login, LDAP, SAML, and Open ID Connect). In a full screen extension, you can prevent a set of users from navigating to other parts of Looker from your extension by adding users to an Extensions Only user group. You can also remove the Looker navigation bar by replacing /extensions with /spartan in the extension URL.

Extension framework requirements

To develop using the Looker extension framework:

You will need LookML developer permissions to your instance.
Your Looker admin must enable the Extension Framework Labs feature.
We recommend familiarity with JavaScript or TypeScript (our examples are written in TypeScript but can be converted to JavaScript).
If you will be building components, we recommend familiarity with React.

Resources for getting started with the Looker extension framework

The following links provide instructions and examples for using the Looker extension framework:

Adding an extension to Looker

To make your extension available from your Looker instance, include the application LookML parameter in your project’s manifest file. Using the kitchen sink extension example:

application: kitchensink { label: "Kitchen sink" url: "http://localhost:8080/bundle.js" entitlements: { local_storage: yes navigation: yes new_window: yes allow_forms: yes allow_same_origin: yes core_api_methods: ["all_connections","search_folders", "run_inline_query", "me", "all_looks", "run_look"] external_api_urls: ["http://127.0.0.1:3000", "http://localhost:3000", "https://*.googleapis.com"] oauth2_urls: ["https://accounts.google.com/o/oauth2/v2/auth"] } }

For details, see the application parameter documentation page.

Permissions assigned to users when using an extension

For most extension use cases, the extension always runs with the permissions granted to the user when they log in.
Any Looker users who have access to at least one of the extension’s underlying models can see the extension listed in the Looker Browse menu:

Users must have access to all of the models that the extension uses for the extension to function fully.
For embedded extensions, the extension takes on the permissions given to the created embed user ID, just like an embedded Look, dashboard, or Explore.
For full screen extensions that use the /spartan option in the extension URL, you can add users to the Extensions Only user group. Users in this group are prevented from viewing Looker pages outside of the extension. Looker admins can customize the Extensions Only group like any other group and assign it a role that has certain permissions and model set access. Users are not required to belong to the Extensions Only group to view a full screen extension; and if a user is not in that user group, the extension will run with the permissions of that logged-in user.