The Topology view in the Red Hat OpenShift console’s Developer perspective is a thoughtfully designed interface that provides a visual representation of an application’s structure. This view helps developers clearly identify one resource type from another, as well as understand the overall communication dynamics within the application. Launched with the 4.2 release of OpenShift, the Topology view has already earned a spotlight in the cloud-native application development arena. The constant feedback cycles and regular follow-ups on the ongoing trends in the developer community have helped to shape up a great experience in the upcoming release. This article focuses on a few showstopper features in the Topology view that were added for OpenShift 4.3.
Toggle between the List view and the Graph view
To address a frequent ask from the user community, the Topology view now comes with a toggle button to quickly switch between the List view and the Graph view for a given project, as shown in Figure 1. While the Graph view comes in handy in use cases requiring cognizance of the role played by individual components in the application architecture, List views can be helpful for more data-focused and investigative tasks. The introduction of this toggle would enable seamless navigation through views irrespective of the contrast in use cases.
Figure 1: Toggle between the List and Graph view.
Choose components through the contextual actions menu
The Topology view offers an elaborate list of components available as a part of the graph, as shown in Figure 2. There are various resource types, connectors, groupings, and items such as event sources, each of which supports a different set of actions in context. Users can access this exclusive menu for each listed item by performing a right-click over them, which further opens a drop-down list with all available actions. Also, users can click anywhere outside the menu to make it disappear from the view.
Figure 2: Access many components through Topology’s Graph view.
Create a binding between resources
The Topology view allows you to create a connection between any pair of resources by dragging a handle from the origin node(s) and dropping it over a target node, as shown in Figure 3. This capability reduces the cognitive load on developers by providing a smart assessment of whether an Operator-managed backing service is available for creating the intended binding. In the absence of an Operator-managed backing service, an annotation-based connection is created.
Figure 3: Create a connection between resources.
Visualize pod transitions in real time
The Topology view in 4.3 provides convenient and up front access to scale up/down and increase/decrease your pod count via the side panel. Similarly, users can also start rollout or recreate pods for a given node from the contextual menu (accessed through a right-click or from the Actions button on the side panel). Upon performing the associated interaction from the side panel, users see a real-time visualization of the transitions that the pods go through, as shown in Figure 4.
Figure 4: Adjust pod settings and view pod transitions in real time.
Delete an application
The Topology view now supports deleting an application from the Graph view. By invoking the contextual menu for the given application grouping—either by performing a right-click or through the side panel—users can access the Delete action, as shown in Figure 5. Upon confirming this action, the application group (comprising of components with the associated label, as defined by the Kubernetes-recommended labels) is deleted.
Figure 5: Delete an application through the Topology Graph view.
Visualize the event sources sink
The Topology view shows elements from Knative Eventing—namely event sources, which visually provide quick insights for developers into which event sources will trigger their application, as shown in Figure 6.
Figure 6: View Knative event sources in the Topology view.
View Knative services and associated revisions
Users can now view Knative services and their associated Revisions and Deployments in the Topology view. The revisions in a service that are in the active traffic block are displayed as a group within the Topology view, along with the information on their traffic consumption, as shown in Figure 7.
Figure 7: View Knative service Revisions and Deployments in the Topology view.
With the continuous evolution of Kubernetes-related technology and the introduction of new practices and integrations, OpenShift is constantly updated to reflect this progression.
Interested in learning more about application development with OpenShift? Check out our resources on application development in OpenShift.
To provide feedback, either join our OpenShift Developer Experience Google Group, where you can participate in discussions or attend our Office Hours Feedback session, or drop us an email with your comments about the OpenShift Console user experience anytime.Last updated: May 13, 2021