OCI Compatible Archives Support

[Virviil]

Description

Add support for non-image OCI artifacts like Helm charts and ArgoCD applications packed as OCI artifacts, requiring a different processing workflow.

Complexity

High - This is a complex task requiring a fundamentally different approach since these artifacts lack standard Docker image structure.

Challenge

Unlike Docker images, OCI artifacts (Helm charts, ArgoCD apps, etc.) have:

• No standard image config structure
• No layer history like Docker images
• Different metadata and annotation handling
• Various artifact types with different internal structures

Tasks

• Research OCI artifact specifications and common types
• Implement artifact type detection from OCI manifest
• Design alternative Git commit structure for non-layered artifacts
• Create custom processors for different artifact types:
  • Helm charts
  • ArgoCD applications
  • Generic OCI artifacts
• Implement metadata extraction specific to each artifact type
• Add comprehensive tests for different artifact scenarios
• Update CLI to handle artifact-specific options

Skills Required

• Rust programming (advanced)
• Deep OCI specification knowledge
• Helm chart understanding
• ArgoCD application structure knowledge
• Complex workflow and architecture design
• Metadata parsing and Git repository design

Technical Challenges

Artifact Detection

// Detect artifact type from manifest annotations
match manifest.annotations.get("org.opencontainers.artifact.type") {
    Some("application/vnd.cncf.helm.chart.content.v1.tar+gzip") => process_helm_chart(),
    Some("application/vnd.argoproj.application+yaml") => process_argo_app(),
    _ => process_generic_artifact(),
}

Different Git Structure

Instead of layer-based commits, create artifact-based structure:

• Initial commit: Artifact metadata
• Content commits: Logical groupings of files
• Preserve artifact-specific annotations and labels

Helm Chart Processing

• Extract Chart.yaml metadata
• Process templates, values, and dependencies
• Maintain Helm-specific directory structure

ArgoCD Application Processing

• Parse application manifests
• Handle Kustomize/Helm source references
• Preserve ArgoCD-specific configurations

Implementation Approach

1. Detection Phase: Identify artifact type from manifest
2. Processing Phase: Use artifact-specific processor
3. Git Generation Phase: Create appropriate repository structure
4. Metadata Phase: Extract and store artifact-specific metadata

Files to Create

• src/artifact_processors/ - New module for artifact handling
• src/artifact_processors/helm.rs - Helm chart processor
• src/artifact_processors/argo.rs - ArgoCD app processor
• src/artifact_processors/generic.rs - Generic artifact processor

Files to Modify

• Main processing pipeline - Add artifact detection
• Git repository generation - Support different structures
• CLI options - Add artifact-specific flags

Expected Impact

Expand oci2git beyond Docker images to support the growing ecosystem of OCI artifacts, making it a comprehensive OCI analysis tool.

This is an advanced task perfect for experienced Hacktoberfest contributors! 🎃

Hacktoberfest 2025 🍂