Shell

Overview

The Shell package provides powerful shell command execution capabilities for OOMOL workflows. It enables you to run shell commands with custom environment variables, control working directories, and capture command output for further processing.

Features

• Shell Command Execution: Run any shell command with full syntax support including pipes, redirects, and command substitution
• Environment Control: Set custom environment variables for command execution
• Working Directory Management: Specify custom working directories for commands
• Output Capture: Capture and process command stdout/stderr output
• JavaScript Integration: Process shell output with JavaScript scriptlets

Core Components

Shell Task

The main shell execution task that provides:

• Command Input: Accepts any valid shell command string
• Environment Variables: Set custom environment variables in KEY=VALUE format
• Working Directory: Optional directory specification for command execution
• Output: Returns combined stdout/stderr as string output

Playground Flow

A demonstration workflow that shows:

• How to execute shell commands with environment variables
• Command output processing with JavaScript
• Integration between shell execution and scriptlet processing

Usage Examples

Basic Command Execution

command: echo "Hello World"

With Environment Variables

command: echo $CUSTOM_VAR
cwd: /tmp
envs: CUSTOM_VAR=Hello

Complex Commands

command: ls -la | grep txt
cwd: /home/user

Technical Details

• Executor: Shell executor with full bash/sh compatibility
• Output: Combined stdout and stderr as single string
• Environment: Variables are appended to existing environment
• Error Handling: Command exit codes are preserved for workflow control

Integration

The shell task integrates seamlessly with other OOMOL components:

• Connect to file processing tasks
• Chain with JavaScript/Python scriptlets
• Use output as input for subsequent workflow nodes