Code Execution

Code execution nodes allow you to run custom JavaScript or Python code within your workflows for complex data transformations, custom logic, or integration with external libraries.

Available Nodes

Node	Description	Documentation
JavaScript	Execute ECMAScript 5.1 compatible JavaScript code in secure sandbox	JavaScript Node →
Python	Execute Python 3.x code code in secure sandbox	Python Node →

Quick Start

JavaScript Node

Execute JavaScript code with access to built-in functions and workflow context:

// Access workflow context - full access to nodes, vars, consts, and user data
var items = ctx.vars.items || [];
var userRole = ctx.user.roles[0] || 'user';
var previousResult = ctx.nodes.dataProcessor.outputs.data || {};
var total = 0;

// Process data (ES5.1 compatible)
for (var i = 0; i < items.length; i++) {
  if (items[i] && items[i].value) {
    total += items[i].value;
  }
}

// Return result (automatically stored in workflow context)
return { 
  total: total, 
  count: items.length,
  processedBy: ctx.user.login,
  workspace: ctx.workspace_slug 
};

Key Features:

ECMAScript 5.1 JavaScript sandbox
Built-in crypto, random, and conversion utilities
Full workflow context access via ctx object (see context docs)
Secure sandboxed execution

→ Learn more about JavaScript nodes

Python Node

Execute Python code with support for external libraries and complex data processing:

# Access full workflow context - nodes, vars, consts, user, and system data
items = args.get('vars', {}).get('items', [])
user_role = args.get('user', {}).get('roles', ['user'])[0]
previous_data = args.get('nodes', {}).get('dataProcessor', {}).get('outputs', {}).get('data', {})
workspace_name = args.get('workspace_slug', 'unknown')

# Process data
processed = []
for item in items:
    if item.get('active'):
        processed.append({
            'id': item['id'],
            'processed_value': item.get('value', 0) * 2,
            'processed_by': args.get('user', {}).get('login', 'system')
        })

# Return result (automatically stored in workflow context)
result = {
    'processed': processed,
    'count': len(processed),
    'workspace': workspace_name,
    'processor_role': user_role
}

Key Features:

Full Python 3.x runtime with built-in libraries
Full workflow context access via args variable (see context docs)
Comprehensive data processing capabilities

→ Learn more about Python nodes

Architecture Overview

JavaScript Nodes

Runtime: ECMAScript 5.1 JavaScript sandbox
Execution: Direct in-process with worker pool
Security: VM sandboxing
Libraries: Built-in utilities only

Python Nodes

Runtime: Python 3.x sandbox environment
Execution: Isolated sandbox execution
Security: Container isolation
Libraries: Python standard library built-in

Common Use Cases

Use Case	Recommended Node	Why
Simple data transformation	JavaScript	Fast, built-in utilities
Complex calculations	Python	Math/statistics libraries, better numerics
API integrations	JavaScript	Built-in HTTP utilities
Advanced data processing	Python	Collections, itertools, statistics
String/XML processing	JavaScript	Built-in conversion utilities
Large dataset processing	Python	Memory efficient, built-in data structures

Best Practices

Universal Guidelines

Validate inputs - Check for required data and proper types
Handle errors gracefully - Use appropriate error handling patterns
Use workflow variables - Access shared data via context
Return structured data - Use objects/dictionaries for results
Keep code focused - Single responsibility per node

Language-Specific

JavaScript: Use only ES5.1 syntax, leverage built-in utilities
Python: Use standard library efficiently, leverage built-in data structures

Workflow Context Access

Both JavaScript and Python nodes have full access to the workflow execution context. For comprehensive documentation, see Workflow Context.

JavaScript:

// Access node outputs, variables, constants, user info, and system data
var nodeData = ctx.nodes.apiCall.outputs.result;
var variables = ctx.vars.userData;
var constants = ctx.consts.API_ENDPOINT;
var userInfo = ctx.user.login;
var workspace = ctx.workspace_slug;

Python:

# Access complete workflow context via args variable
node_data = args.get('nodes', {}).get('apiCall', {}).get('outputs', {}).get('result')
variables = args.get('vars', {}).get('userData')
constants = args.get('consts', {}).get('API_ENDPOINT')
user_info = args.get('user', {}).get('login')
workspace = args.get('workspace_slug')

Getting Started

Choose your language based on your use case and requirements
Read the specific documentation for your chosen node type
Review best practices for robust, maintainable code
Test with simple examples before building complex logic

JavaScript Node Documentation →
Python Node Documentation →
Best Practices →

Code Execution

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