Run on Pod (ROP)

Why Use Run on Pod?

• Convenience: Easily execute scripts or binaries directly on Kubernetes pods without manual copying or complex kubectl commands.
• Flexibility: Support for both script and binary execution, with automatic detection of file type and custom runners.
• Efficiency: Streamlined workflow for developers and operators working with Kubernetes environments.
• Safety: Built-in confirmation prompts and context awareness to prevent accidental executions.

Installation

To install Run on Pod, run:

go install github.com/marianozunino/rop@latest

Or download the binary from the GitHub releases

Usage

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Usage:
  rop [flags]
  rop [command]

Available Commands:
  completion  Generate the autocompletion script for the specified shell
  help        Help about any command
  version     Print the version number of rop

Flags:
  -c, --context string     Kubernetes context (autocomplete available from kube config)
  -n, --namespace string   Kubernetes namespace (defaults to current namespace if not provided)
  -p, --pod string         The target pod name
      --container string   The container name (optional for single-container pods)
  -f, --file string        The file path to execute
  -a, --args stringArray   File arguments
  -d, --dest-path string   Destination path for the script or binary (default "/tmp")
  -r, --runner string      Custom runner for the script (e.g., 'python', 'node')
  -t, --type string        File type: 'script', 'binary', or 'auto' (default "auto")
      --no-confirm         Skip confirmation prompt
  -v, --verbose            Verbose output
  -h, --help               help for rop

Use "rop [command] --help" for more information about a command.

Examples

1. Run a script on a pod:

   rop -c my-context -f ./myscript.sh -p my-pod
   

2. Execute a binary with arguments:

   rop -c prod-cluster -f ./myapp -p backend-pod -t binary -a "--verbose" -a "--config=/etc/myapp.conf"
   

3. Run in a specific container of a multi-container pod:

   rop -c dev-cluster -f ./debug.py -p monitoring-pod --container logger
   

4. Execute without confirmation prompt:

   rop -c staging -f ./update-db.sh -p db-pod --no-confirm
   

5. Use a custom runner for a script:

   rop -c dev-cluster -f ./script.js -p nodejs-pod -r node
   

6. Specify a custom destination path:

   rop -c prod-cluster -f ./config.yaml -p config-pod -d /app/config
   

7. Test out the completion:

   rop completion zsh > /tmp/completion; source /tmp/completion
   

Configuration

Run on Pod doesn't require a configuration file. All options are specified via command-line flags.

How Does Run on Pod Work?

1. Context Awareness: Uses the specified Kubernetes context to ensure you're operating in the correct cluster. Contexts can be auto-completed from the kube config.
2. Namespace Handling: The namespace can also be auto-completed, and if not provided, it defaults to the current namespace of the context.
3. File Detection: Automatically detects whether the file is a script or binary, with an option to override.
4. Pod Selection: Targets the specified pod and optionally a specific container within that pod.
5. File Transfer: Securely copies the file to the target pod.
6. Execution: Runs the file within the pod's context, capturing and displaying output.
7. Cleanup: Removes the transferred file from the pod after execution.

Safety Features

• Confirmation prompt before execution (can be disabled with --no-confirm flag)
• Clear display of target context, pod, and container before execution
• Automatic file type detection to prevent incorrect execution methods

Notes

• Kubernetes Version: This tool has been tested with Kubernetes 1.20+. If you encounter issues with other versions, please report them.
• File Size Limit: Be aware of potential limitations on file sizes that can be transferred to pods. Very large files may cause issues.
• Security: Ensure you have the necessary permissions in your Kubernetes cluster to execute files on pods.
• Network Dependency: Requires network access to your Kubernetes cluster. Performance may vary based on network conditions.
• Custom Runners: When using the --runner flag, ensure that the specified runner is available in the target pod's container.

Contributing

Contributions to Run on Pod are welcome! Please feel free to submit pull requests, create issues for bugs and feature requests, or contribute to the documentation.

License

Run on Pod is released under the MIT License. See the LICENSE file for more details.