n8n Workflow Automation

What is n8n?

n8n is an open-source workflow automation platform. It enables non-technical users and developers to build integration workflows without complex code. Think of it as IFTTT but self-hosted, extensible, and enterprise-ready.

Core Components

• Workflow: Visual representation of automation steps
• Nodes: Individual actions or integrations
• Connections: Data flow between nodes
• Triggers: Webhooks, scheduled events, polls
• Credentials: Secure auth storage for services

Workflow Types

• Trigger-based: Starts from webhook/schedule
• Always-on: Continuous polling or listening
• Manual: Executed by user interaction
• Cron: Time-based recurring automations

Key Benefits

• No server infrastructure needed (vs custom code)
• Visual workflow design reduces errors
• Quick integration of 400+ pre-built nodes
• Extensible via custom code in JavaScript
• Ideal for cross-system synchronization

Custom JavaScript Node

Use the Code node to write custom JavaScript for logic that exceeds basic node capabilities. Access input data via $input, manipulate it, and return structured output.

// Example: Transform input data
const user = $input.all()[0].json;
return {
    fullName: `${user.first} ${user.last}`,
    email: user.email,
    timestamp: new Date().toISOString()
};

HTTP Requests

The HTTP node is powerful for calling any REST API. Configure method, URL, headers, and body. Use expression language to reference data from previous nodes.

// Example body with expressions
{
    "userId": "{{ $node.SplitData.json.id }}",
    "action": "update",
    "timestamp": "{{ $now.toISOString() }}"
}

Conditional Logic

Use IF nodes to branch workflows. Routes data through different paths based on conditions. Combine with Switch nodes for multiple branches. Essential for error handling and data validation.

Error Handling

Add error handlers to workflow paths. Prevent cascading failures by catching and logging errors. Use Try-Catch pattern: main flow + error handler node that logs or notifies.

Loop Nodes

Process collections of data iteratively. For-in loop iterates over arrays. Useful for batch operations, syncing multiple records, or building aggregated results.

Data Transformation

• Item lists: Filter and sort arrays
• Merge: Combine multiple inputs
• Set: Rename, add, remove fields
• Function: Apply functions to fields
• Expression editor: Advanced data mapping

Data Sync Pattern

Webhook receives data → Transform fields → Query destination database → Update existing or create new record → Log result

Notification Pattern

Trigger (form submission, API call) → Extract relevant data → Format message → Send via email/Slack/SMS → Log delivery

Approval Workflow

Request received → Store in database → Send approval request → Wait for response → Execute action based on decision

Scheduled Reports

Cron trigger on schedule → Query data from multiple sources → Transform and aggregate → Format as PDF/CSV → Email to stakeholders

Multi-System Sync

Change in System A → Fetch full context → Transform for System B format → Update System B → Log sync event → Alert on conflict

Webhook Receiver

Expose webhook endpoint → Validate request signature → Queue processing → Handle async without blocking source system → Return 200 immediately

Workflow Design

• Use meaningful node names for clarity
• Add comments for complex sections
• One workflow per integration concern
• Use sub-workflows for reusable logic
• Keep main flow simple, delegate to sub-workflows

Error Management

• Always add error handlers to critical nodes
• Log errors with context for debugging
• Implement retry logic with exponential backoff
• Set up alerting for workflow failures
• Use dead-letter queues for failed records

Security & Credentials

• Never hardcode credentials in workflows
• Use n8n's credential system exclusively
• Rotate credentials regularly
• Use environment variables for configuration
• Restrict webhook endpoints with validation

Performance Optimization

• Paginate API requests to avoid timeouts
• Filter data early to reduce processing
• Use batch operations when available
• Implement caching for reference data
• Monitor workflow execution times

SaaS & Communication

• Gmail, Outlook, SendGrid
• Slack, Teams, Discord
• Calendars, Typeform, Airtable

Databases

• PostgreSQL, MySQL, MongoDB
• Firebase, Supabase
• DynamoDB, Elasticsearch

Developer Tools

• GitHub, GitLab, Bitbucket
• Jira, Linear, Asana
• Docker, AWS, GCP

Generic Connectors

• HTTP requests (any REST API)
• Webhooks (receive data)
• SFTP, FTP file transfer
• Custom code execution