This tool scans a Rust workspace for crates containing Docker/Kubernetes metadata in their Cargo.toml files and generates a complete, production-ready Helm chart with deployments, services, ingress, and configuration templates.

Features

Automatic Service Discovery: Scans all Cargo.toml files in a workspace to find services with Kubernetes metadata
Complete Helm Chart Generation: Creates Chart.yaml, values.yaml, deployment templates, service templates, ingress template, and helper templates
Metadata Extraction: Uses [package.metadata.kube] sections from Cargo.toml files to extract:
- Docker image names
- Service ports
- Replica counts
- Service names
Production Ready: Generated charts include health checks, resource limits, node selectors, affinity rules, and tolerations
Helm Best Practices: Follows Helm chart conventions and passes helm lint validation

Installation

Build the tool from source:

cd helm-chart-tool
cargo build --release

The binary will be available at target/release/helm-chart-tool.

Usage

Basic Usage

./target/release/helm-chart-tool --workspace /path/to/rust/workspace --output ./my-helm-chart

Command Line Options

--workspace, -w PATH: Path to the workspace root (default: .)
--output, -o PATH: Output directory for the Helm chart (default: ./helm-chart)
--name, -n NAME: Name of the Helm chart (default: predict-otron-9000)

Example

# Generate chart from current workspace
./target/release/helm-chart-tool

# Generate chart from specific workspace with custom output
./target/release/helm-chart-tool -w /path/to/my/workspace -o ./charts/my-app -n my-application

Cargo.toml Metadata Format

The tool expects crates to have Kubernetes metadata in their Cargo.toml files:

[package]
name = "my-service"
version = "0.1.0"

# Required: Kubernetes metadata
[package.metadata.kube]
image = "ghcr.io/myorg/my-service:latest"
replicas = 1
port = 8080

# Optional: Docker Compose metadata (currently not used but parsed)
[package.metadata.compose]
image = "ghcr.io/myorg/my-service:latest"
port = 8080

Required Fields

image: Full Docker image name including registry and tag
port: Port number the service listens on
replicas: Number of replicas to deploy (optional, defaults to 1)

Generated Chart Structure

The tool generates a complete Helm chart with the following structure:

helm-chart/
├── Chart.yaml              # Chart metadata
├── values.yaml             # Default configuration values
├── .helmignore            # Files to ignore when packaging
└── templates/
    ├── _helpers.tpl        # Template helper functions
    ├── ingress.yaml        # Ingress configuration (optional)
    ├── {service}-deployment.yaml    # Deployment for each service
    └── {service}-service.yaml       # Service for each service

Generated Files

Chart.yaml

Standard Helm v2 chart metadata
Includes keywords for AI/ML applications
Maintainer information

values.yaml

Individual service configurations
Resource limits and requests
Service types and ports
Node selectors, affinity, and tolerations
Global settings and ingress configuration

Deployment Templates

Kubernetes Deployment manifests
Health checks (liveness and readiness probes)
Resource management
Container port configuration from metadata
Support for node selectors, affinity, and tolerations

Service Templates

Kubernetes Service manifests
ClusterIP services by default
Port mapping from metadata

Ingress Template

Optional ingress configuration
Disabled by default
Configurable through values.yaml

Example Output

When run against the predict-otron-9000 workspace, the tool generates:

$ ./target/release/helm-chart-tool --workspace .. --output ../generated-helm-chart
Parsing workspace at: ..
Output directory: ../generated-helm-chart
Chart name: predict-otron-9000
Found 4 services:
  - leptos-app: ghcr.io/geoffsee/leptos-app:latest (port 8788)
  - inference-engine: ghcr.io/geoffsee/inference-service:latest (port 8080)
  - embeddings-engine: ghcr.io/geoffsee/embeddings-service:latest (port 8080)
  - predict-otron-9000: ghcr.io/geoffsee/predict-otron-9000:latest (port 8080)
Helm chart generated successfully!

Validation

The generated charts pass Helm validation:

$ helm lint generated-helm-chart
==> Linting generated-helm-chart
[INFO] Chart.yaml: icon is recommended
1 chart(s) linted, 0 chart(s) failed

Deployment

Deploy the generated chart:

# Install the chart
helm install my-release ./generated-helm-chart

# Upgrade the chart
helm upgrade my-release ./generated-helm-chart

# Uninstall the chart
helm uninstall my-release

Customization

Customize the deployment by modifying values.yaml:

# Enable ingress
ingress:
  enabled: true
  className: "nginx"
  hosts:
    - host: my-app.example.com

# Adjust resources for a specific service
predict_otron_9000:
  replicas: 3
  resources:
    limits:
      memory: "4Gi"
      cpu: "2000m"
    requests:
      memory: "2Gi"
      cpu: "1000m"

Requirements

Rust 2021+ (for building the tool)
Helm 3.x (for deploying the generated charts)
Kubernetes cluster (for deployment)

Limitations

Currently assumes all services need health checks on /health endpoint
Resource limits are hardcoded defaults (can be overridden in values.yaml)
Ingress configuration is basic (can be customized through values.yaml)

Contributing

Add new features to the tool
Test with various Cargo.toml metadata configurations
Validate generated charts with helm lint
Ensure charts deploy successfully to test clusters

License

This tool is part of the predict-otron-9000 project and follows the same license terms.