🚀 helm-in-pod

⚡ A Helm plugin to run any command (helm/kubectl/etc) inside a Kubernetes cluster

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🤔 Why?

📡 Network Latency Problem

When helm runs commands from your local machine, network latency to distant Kubernetes clusters can significantly slow down operations, especially with large releases containing many manifests.

helm-in-pod solves this by running Helm commands directly inside the cluster, minimizing network latency between the client and Kubernetes API.

✨ Key Benefits

Feature	Description
🏃‍♂️ Fast Execution	Run commands inside the cluster for minimal latency
🔧 Any Command	Execute helm, kubectl, or any other command
📦 Repository Sync	Automatically copies all host Helm repositories
📁 File Transfer	Copy files/folders from host to pod
🌍 Environment Variables	Set custom environment variables in the pod
🐳 Custom Images	Use any Docker image for execution

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📋 Requirements

• 🎯 Helm 3 installed on host machine

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🚀 Installation

📥 Quick Install/Update

# Install or update the plugin
(helm plugin uninstall in-pod || true) && helm plugin install --verify=false https://github.com/Noksa/helm-in-pod

💡 You can specify any existing version from the releases page

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⚡ NEW: Daemon Mode

🔥 Run multiple commands without pod recreation overhead!

# Start once
helm in-pod daemon start --name dev --copy-repo

# Execute many times - INSTANT! ⚡
helm in-pod daemon exec --name dev -- "helm list -A"
helm in-pod daemon exec --name dev -- "helm upgrade myapp ..."

# Stop when done
helm in-pod daemon stop --name dev

10x faster for multiple operations! Perfect for CI/CD, interactive development, and batch deployments.

👉 Read Full Daemon Mode Documentation

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📖 Usage

🔍 Getting Help

helm in-pod --help

🎯 Basic Syntax

helm in-pod exec [FLAGS] -- "COMMAND"

🔧 Available Flags

Flag	Short	Description
--copy	-c	Copy files/folders from host to pod
--env	-e	Set environment variables
--subst-env	-s	Substitute environment variables from host
--image	-i	Use custom Docker image
--update-repo		Update specified Helm repositories
--tolerations		Pod tolerations for node taints
--node-selector		Pod node selectors for node targeting
--host-network		Use host network in pod

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⚙️ How It Works

🔄 Execution Flow

When you run helm in-pod exec, the following happens:

1. 🏗️ Pod Creation: Creates a new helm-in-pod pod in the helm-in-pod namespace
2. 📚 Repository Sync: Copies all existing Helm repositories from host to pod
3. 🔄 Repository Updates: Fetches updates for specified repositories
4. 📁 File Transfer: Copies specified files/directories to the pod
5. ▶️ Command Execution: Runs your specified command inside the pod

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💡 Examples

🔍 Basic Operations

Get all pods

helm in-pod exec -- "kubectl get pods -A"

List Helm releases

helm in-pod exec -- "helm list -A"

📦 Installing Charts

Simple installation

# Add repository on host
helm repo add bitnami https://charts.bitnami.com/bitnami --force-update

# Install from pod
helm in-pod exec --update-repo bitnami -- \
  "helm install -n bitnami-nginx --create-namespace bitnami/nginx nginx"

Installation with custom values

helm repo add bitnami https://charts.bitnami.com/bitnami --force-update

# Copy values file and install
helm in-pod exec \
  --copy /home/alexandr/bitnami/nginx_values.yaml:/tmp/nginx_values.yaml \
  --update-repo bitnami -- \
  "helm upgrade -i -n bitnami-nginx --create-namespace bitnami/nginx nginx -f /tmp/nginx_values.yaml"

⚠️ Important: Use the pod path (/tmp/nginx_values.yaml) in the helm command, not the host path

🗄️ SQL Backend Configuration

Using environment variables

helm in-pod exec \
  -e "HELM_DRIVER=sql" \
  -e "HELM_DRIVER_SQL_CONNECTION_STRING=postgresql://helmpostgres.helmpostgres:5432/db?user=user&password=password" \
  --copy /home/alexandr/bitnami/nginx_values.yaml:/tmp/nginx_values.yaml \
  --update-repo bitnami -- \
  "helm upgrade -i -n bitnami-nginx --create-namespace bitnami/nginx nginx -f /tmp/nginx_values.yaml"

Using host environment substitution

# Set environment variables on host
export HELM_DRIVER=sql
export HELM_DRIVER_SQL_CONNECTION_STRING=postgresql://helmpostgres.helmpostgres:5432/db?user=user&password=password

# Use them in pod
helm in-pod exec \
  -s "HELM_DRIVER,HELM_DRIVER_SQL_CONNECTION_STRING" \
  --copy /home/alexandr/bitnami/nginx_values.yaml:/tmp/nginx_values.yaml \
  --update-repo bitnami -- \
  "helm upgrade -i -n bitnami-nginx --create-namespace bitnami/nginx nginx -f /tmp/nginx_values.yaml"

🔍 Advanced Operations

Using host network

# Run with host network for network troubleshooting
helm in-pod exec --host-network -- "kubectl get pods -A"

# Access services on host network
helm in-pod exec --host-network -- "curl http://localhost:6443"

# Test DNS from host perspective
helm in-pod exec --host-network -- "nslookup kubernetes.default.svc.cluster.local"

Running on tainted nodes

# Tolerate all taints
helm in-pod exec --tolerations "::Exists" -- "helm list -A"

# Tolerate specific key with any effect
helm in-pod exec --tolerations "key=:NoSchedule:Exists" -- "helm list -A"

# Tolerate specific key-value pair
helm in-pod exec --tolerations "key=value:NoSchedule:Equal" -- "helm list -A"

# Multiple tolerations
helm in-pod exec \
  --tolerations "node-role.kubernetes.io/control-plane=:NoSchedule:Exists" \
  --tolerations "dedicated=special:NoExecute:Equal" -- \
  "helm list -A"

Targeting specific nodes with node selectors

# Run on nodes with specific label
helm in-pod exec --node-selector "disktype=ssd" -- "helm list -A"

# Run on control plane nodes (empty value)
helm in-pod exec --node-selector "node-role.kubernetes.io/control-plane=" -- "helm list -A"

# Multiple node selectors
helm in-pod exec \
  --node-selector "disktype=ssd,environment=production" -- \
  "helm list -A"

# Combine with tolerations for control plane
helm in-pod exec \
  --node-selector "node-role.kubernetes.io/control-plane=" \
  --tolerations "node-role.kubernetes.io/control-plane=:NoSchedule:Exists" -- \
  "helm list -A"

Helm diff with custom configuration

helm in-pod exec \
  -e "HELM_DIFF_NORMALIZE_MANIFESTS=true,HELM_DIFF_USE_UPGRADE_DRY_RUN=true,HELM_DIFF_THREE_WAY_MERGE=true" \
  --copy /home/alexandr/bitnami/nginx_values.yaml:/tmp/nginx_values.yaml \
  --update-repo bitnami -- \
  "helm diff upgrade -n bitnami-nginx --create-namespace bitnami/nginx nginx -f /tmp/nginx_values.yaml"

Custom Docker images

# Specific Helm version
helm in-pod exec -i "alpine/helm:3.12.1" -- "helm list -A"

# Custom image with additional tools
helm in-pod exec -i "alpine:3.18" -- "apk add curl --no-cache && curl google.com"