Chart Inspector

Chart Inspector is a service that provides endpoints for inspecting Helm charts. It allows users to retrieve resources from Helm charts and perform various operations on them.

Table of Contents

• Overview
• Architecture
• API

Overview

Chart Inspector is a Krateo tool that enables the composition-dynamic-controller to generate its own RBAC policy. It returns a list of resources involved in a chart installation, considering the current cluster state using helm template --server, which evaluates lookups dynamically.

The /resources endpoint wraps the http.RoundTripper of the Helm client with a tracer that intercepts requests made to the Kubernetes API server. It then returns a list of resources involved in the chart installation.

Architecture

API

API Endpoints

Retrieve Helm Chart Resources

• Endpoint: /resources

• Method: GET

• Query Parameters (required):

  • compositionName (string): The name of the Composition resource.
  • compositionNamespace (string): The namespace of the Composition resource.
  • compositionDefinitionName (string): The name of the CompositionDefinition resource.
  • compositionDefinitionNamespace (string): The namespace of the CompositionDefinition resource.
  • compositionVersion (string): The API version of the Composition (e.g. v1alpha1).
  • compositionResource (string): The plural resource name for Compositions (e.g. compositions).

• Query Parameters (optional):

  • compositionGroup (string): Composition group (default: composition.krateo.io).
  • compositionDefinitionGroup (string): CompositionDefinition group (default: core.krateo.io).
  • compositionDefinitionVersion (string): CompositionDefinition version (default: v1alpha1).
  • compositionDefinitionResource (string): CompositionDefinition resource name (default: compositiondefinitions).

• Response: JSON array of resources touched by the Helm chart template.

Example Request

curl "http://localhost:8081/resources?compositionName=my-composition&compositionNamespace=default&compositionDefinitionName=my-cd&compositionDefinitionNamespace=default&compositionVersion=v1alpha1&compositionResource=compositions"

Swagger Documentation

Chart Inspector provides Swagger documentation for its API. You can access it at:

http://localhost:8081/swagger/

Environment variables

Some environment variables affect the behavior of Chart Inspector and the components used in tests.

• DEBUG: If set (e.g. DEBUG=true) enables debug output used in tests and local runs. Default is false.
• HELM_CHART_CACHE_DIR:Directory where downloaded charts are temporarily stored. If not set, /tmp/helmchart-cache is used. The cache is used by getter.Get (getter.go) to avoid repeated downloads.