The KubeMQ messaging platform uses Operators to help you build complex and scalable messaging services with minimal coding and overhead.
Join the DZone community and get the full member experience. Over the last several years, the adoption of Kubernetes has increased tremendously. In fact, according to a Cloud Native Computing Foundation (CNCF) survey,78% of respondents in late 2019 were using Kubernetes in production. Leveraging Kubernetes allows organizations to create a management layer to commodify clouds themselves and build cross- or hybrid-cloud deployments that hide the provider-specific implementation details from the rest of the team. One crucial part of the Kubernetes ecosphere is Operators — a tool initially introduced by CoreOS in 2016 to utilize the Kubernetes APIs themselves to deploy and manage the state of applications. Operators are a critical part of the deployment and operation of applications in a cross/hybrid environment. They can help manage and maintain state across a federated Kubernetes deployment (multiple Kubernetes clusters running together) or even across clusters. But what exactly are Operators, and how do they help manage these stateful applications? Let’s take a look at Operators in detail, how they work within Kubernetes, and how the KubeMQ messaging platform uses Operators to help you build complex and scalable messaging services with minimal coding and overhead. At a high level, Operators allow you to automate tasks beyond what Kubernetes natively provides. Operators are software extensions that hook into Kubernetes APIs and the control plane to manage a custom resource (CR) — or an extension to the Kubernetes API. The CR describes the desired state of the application, and the control plane component (the Operator itself) monitors the CR to ensure that the application is running as expected. For example, an Operator might deploy and scale a pod, take and restore a backup, manage network services and ingresses, or manage a persistent data store. Since Operators hook into native Kubernetes tools like kubectl, they become a common language for managing complex deployments where the state is involved.
