N8N Fouten Oplossen: 25+ Meest Voorkomende Errors & Oplossingen (2025)

Oplossing 1: Correct Expression Wrapping

{
  "name": {{ $json.name }},
  "email": {{ $json.email }}
}

{
  "name": "{{ $json.name }}",
  "email": "{{ $json.email }}"
}

Let op: Strings moeten ALTIJD tussen quotes, ook als ze uit expressions komen!

Oplossing 1: Gebruik .first(), .last(), of .all() in plaats van .item

Complete Webhook Debug Flow

// Webhook response handler met error checking
const webhookData = $input.item.json;

// Valideer webhook data
if (!webhookData || Object.keys(webhookData).length === 0) {
  return {
    error: true,
    message: "Empty webhook payload",
    timestamp: new Date().toISOString()
  };
}

// Check voor required fields
const requiredFields = ['id', 'action', 'data'];
const missingFields = requiredFields.filter(field => !webhookData[field]);

if (missingFields.length > 0) {
  return {
    error: true,
    message: `Missing fields: ${missingFields.join(', ')}`,
    received: Object.keys(webhookData)
  };
}

// Process webhook data
return {
  success: true,
  processed: webhookData,
  timestamp: new Date().toISOString()
};

Oplossing 2: Production Fix met Custom CA

# Environment variables voor custom certificates
NODE_EXTRA_CA_CERTS=/path/to/ca-bundle.crt
NODE_TLS_REJECT_UNAUTHORIZED=0  # Alleen als laatste redmiddel!

# Docker compose aanpassing
environment:
  - NODE_EXTRA_CA_CERTS=/certs/ca-bundle.crt
volumes:
  - ./certs:/certs:ro

Oplossing 1: Granular Timeout Control

# Environment variables voor verschillende timeout types
N8N_DEFAULT_REQUEST_TIMEOUT=120000      # 2 minuten voor HTTP requests
QUEUE_WORKER_TIMEOUT=300000              # 5 minuten voor workers
EXECUTIONS_TIMEOUT=3600                  # 1 uur max execution time
EXECUTIONS_TIMEOUT_MAX=7200              # 2 uur absolute max

# Per-node timeout in HTTP Request
{
  "timeout": 300000,           // 5 minuten
  "retry": {
    "maxTries": 3,
    "waitBetweenTries": 5000    // 5 seconden tussen retries
  }
}

Oplossing 1: Safe JSON Parser met Error Details

// Robuuste JSON parser met detailed error reporting
function safeJsonParse(jsonString) {
  try {
    return {
      success: true,
      data: JSON.parse(jsonString)
    };
  } catch (error) {
    // Extract error position
    const match = error.message.match(/position (\d+)/);
    const position = match ? parseInt(match[1]) : 0;
    
    // Find problematic part
    const start = Math.max(0, position - 20);
    const end = Math.min(jsonString.length, position + 20);
    const snippet = jsonString.substring(start, end);
    
    // Common fixes
    let fixed = jsonString;
    
    // Try to fix single quotes
    if (jsonString.includes("'")) {
      fixed = jsonString.replace(/'/g, '"');
      try {
        return {
          success: true,
          data: JSON.parse(fixed),
          warning: 'Auto-fixed single quotes to double quotes'
        };
      } catch (e) {}
    }
    
    // Try to fix trailing commas
    fixed = jsonString.replace(/,\s*}/g, '}').replace(/,\s*]/g, ']');
    try {
      return {
        success: true,
        data: JSON.parse(fixed),
        warning: 'Auto-fixed trailing commas'
      };
    } catch (e) {}
    
    return {
      success: false,
      error: error.message,
      position: position,
      snippet: snippet,
      line: (jsonString.substring(0, position).match(/\n/g) || []).length + 1
    };
  }
}

// Gebruik het zo:
const result = safeJsonParse($json.rawData);

if (!result.success) {
  throw new Error(`JSON Parse Error at position ${result.position}: ${result.snippet}`);
}

return result.data;

Oplossing 1: Complete Environment Setup

# .env file structure
# Database
DB_TYPE=postgres
DB_HOST=localhost
DB_PORT=5432
DB_USER=n8n
DB_PASSWORD=secretpassword
DB_DATABASE=n8n

# N8N Configuration
N8N_HOST=0.0.0.0
N8N_PORT=5678
N8N_PROTOCOL=https
N8N_BASIC_AUTH_ACTIVE=true
N8N_BASIC_AUTH_USER=admin
N8N_BASIC_AUTH_PASSWORD=adminpassword

# Execution
EXECUTIONS_PROCESS=main
EXECUTIONS_TIMEOUT=3600
EXECUTIONS_TIMEOUT_MAX=7200

# Security
N8N_ENCRYPTION_KEY=your-encryption-key
WEBHOOK_URL=https://your-domain.com/webhook