# Entando Component Repository
The Entando Component Repository (ECR) is meant to be a repository to share reusable components among different Entando instances.
The following glossary relates to the ECR and related concepts:
An Entando component - simply referred to as component - is a piece of reusable code/resource to be used in an Entando widget, page or application. Examples of components are widgets, microfrontends, content-types, labels, plugins, and static resources
# ECR Bundle
An ECR bundle - is a package containing one or more components and a 'descriptor.yaml' file providing information about the bundle. The bundle is published on an Git registry and is shared with an Entando application using the EntandoDeBundle custom resource.
# EntandoDeBundle custom resource
The EntandoDeBundle custom resource is a Kubernetes custom resource readable by the Entando6 operator. It’s used to provide information about an ECR bundle and make the bundle available in kubernetes for the entando-component-manager.
The entando-component-manager - a.k.a component-manager is part of the Entando6 app and dialogs both with the Kubernetes cluster via the entando-k8s-service and with the entando-core. The entando-component-manager reads the bundles from the cluster and exposes them via an API accessible from AppBuilder. The component-manager is also responsible of the installation/removal of components from entando-core
The Entando-K8S-Service is part of the Entando infrastructure and is responsible for the low-level communication with the K8S cluster API.
From an architectural point of view, the ECR is composed of
- The EntandoDeBundles which contain the metadata associated with a bundle
- The Entando-k8s-service which reads the bundles from the cluster/namspace(s) and serves them via a consumable API
- The Component-manager which creates the connection between the EntandoApp and the K8S-service.
# Example flow
The user lands on the ECR page in app-builder and wants to see the list of bundles shared with that EntandoApp
AppBuilder asks the component-manager for the list of available bundles
Component-manager queries the k8s-service to get the available bundles
The k8s-service queries the cluster/namespace(s) it is able to read from for available bundles and returns the list to the component-manager
Component-manager returns a list to App-Builder
The user is able to see the available bundles and is able to install one or more of them