Understanding Ambari Views

from a Development, Persona, Versions and Deployment perspective.

Apache Ambari includes the Ambari Views Framework, which enables developers to create UI components, or Views, that “plug into” the Ambari Web interface. Ambari automatically creates and presents to users some instances of Views, if the service used by that View is added to the cluster. For example, if Apache YARN service is added to the cluster, the YARN Queue Manager View displays to Ambari web users. In other cases, the Ambari Admin user must manually create a view instance.

Developing and using Views enables you to extend and customize the Ambari web to meet your specific needs.

Using Views also extends your Ambari implementation to allow third parties to plug in new resource types, along with APIs, providers, and UIs to support them. Views are deployed on the Ambari Server, which enables Ambari Admins to create View instances and set access privileges for users and groups.

The following sections describe the basics of Views and how to deploy and manage View instances in Ambari:

Views are basically web applications that can be “plugged in to” Ambari. Just like a typical web application, a View can include server-side resources and client-side assets. Server-side resources, which are written in Java, can integrate with external systems (such as cluster services) and expose REST end-points that are used by the view. Client-side assets, such as HTML, JavaScript, and CSS, provide the UI for the view that is rendered in the Ambari web interface.

Development:

Ambari Views Framework Ambari exposes the Views Framework as the basis for View development. The Framework provides the following:

Method for describing and packaging a View
Method for deploying a View
Framework services for a View to integrate with Ambari
Method for managing View versions, instances, and permissions

The Ambari Views framework is separate from Views themselves. The framework is a core feature of Ambari that you use to create, deploy, integrate, and manage your own, custom views.

You develop and deliver a view by performing the following tasks:

Develop the View (similar to how you would build a web application)
Package the View (similar to a WAR)
Deploy the View to Ambari (using the Ambari Administration interface)
Create and configure instances of the View (performed by Ambari Admins)

Persona:

Three user persona interact with Views:

View developer: Person who builds the front end and back end of a View and uses the framework services available during development. The developer creates the View, resulting in a View package that is delivered to an Ambari Admin.
Ambari Admin: Ambari user that has Ambari Admin privilege and uses the Views Management section of the Ambari Administration interface to create and managing instances of Views. Ambari Admin also deploys the View packages delivered by the View developer.
View user: Ambari user that has access to one or more Views in the Ambari web (basically, the end user).

Versions:

Each View must have a unique name, although it can have one or more View versions. Each View name and version combination is a single View package. After a View package is deployed, Ambari Admins can create View instances, each of which is identified by a unique View instance name. The Ambari Admin can then set access permissions for each View instance.

Deployment:

Views can be deployed and managed in the operational Ambari Server, the Ambari Server operating your cluster. Alternatively, Views can be deployed and managed in one or more separate standalone Ambari Servers. Running standalone Ambari Server instances is useful when users who will access views will not have (and should not) have access to the operational Ambari Server. You can run one or more separate standalone Ambari Server instances to scale-out your solution for handling a large number of users.

The following Ambari views currently available to you:

Yarn Queue Manager View: Provides a visual way to configure YARN capacity scheduler queue capacity.
Files View: Allows you to browse the HDFS file system.
SmartSense View: Allows you to capture bundles, set bundle capture schedule, and view and download captured bundles.
Workflow Manager View: Allows you to easily create and schedule workflows and monitor workflow jobs.

Subsequent chapters in this guide describe tasks performed by an Ambari Administrator to make Views available to users in their Ambari-managed cluster. This guide does not describe View development and packaging.