ExitCodeZer0
Posts
Build Powerful PDF Workflows with n8n and FileSlap API

Build Powerful PDF Workflows with n8n and FileSlap API

Create sophisticated automation workflows that generate professional PDFs using n8n and our cloud-based API

July 10, 2025

Why Use n8n for PDF Generation?

n8n is the ultimate automation platform for developers and power users who need:

Complex workflow logic - Conditional branching, loops, and data transformation
Self-hosted control - Keep your data and workflows on your own infrastructure
Advanced integrations - Connect to databases, APIs, and custom services
Visual workflow builder - Design complex automations without coding
Extensive node library - 200+ built-in integrations plus custom nodes

While n8n has some basic PDF capabilities, the FileSlap API integration unlocks unlimited possibilities for creating professional, branded PDFs from any HTML content with advanced formatting and styling.

Setting Up FileSlap API in n8n

1. Get Your API Key

First, sign up at fileslap.com and grab your API key. It's free to start with 50 conversions per month.

2. Configure the HTTP Request Node

n8n's HTTP Request node is perfect for integrating with the FileSlap API. Here's how to set it up:

Basic HTML to PDF Workflow

Step 1: Create Your Workflow

Open n8n and create a new workflow
Add a Trigger node (Webhook, Schedule, or Manual)
Add an HTTP Request node for FileSlap API
Add Output nodes for saving/sending the PDF

Step 2: Configure the HTTP Request Node

Node Settings:

Method: POST
URL: https://api.fileslap.com/api/convert
Authentication: Header Auth
Header Name: X-API-KEY
Header Value: YOUR_API_KEY

Request Body (JSON):

{
  "html": "{{$json.html_content}}"
}

Step 3: Handle the Response

The HTTP Request node will return the PDF as binary data. Connect it to:

Write Binary File node (save locally)
Google Drive node (upload to cloud)
Gmail node (send as attachment)
Slack node (upload to channel)

Advanced n8n Workflows

1. Dynamic Invoice Generation

Workflow: Database → Template → PDF → Email

Setup:

Database node: Query orders from your database
Code node: Transform data into HTML template
HTTP Request node: Convert HTML to PDF via FileSlap
Gmail node: Send PDF invoice to customer
Database node: Update order status

Code Node Example (JavaScript):

const orders = $input.all();
const htmlTemplates = [];

for (const order of orders) {
  const html = `
    <!DOCTYPE html>
    <html>
    <head>
        <title>Invoice #${order.order_number}</title>
        <style>
            body { font-family: Arial, sans-serif; margin: 40px; }
            .header { text-align: center; border-bottom: 2px solid #333; }
            .invoice-details { margin: 30px 0; }
            .items-table { width: 100%; border-collapse: collapse; }
            .total { font-weight: bold; text-align: right; }
        </style>
    </head>
    <body>
        <div class="header">
            <h1>INVOICE</h1>
            <p>Order #${order.order_number} | Date: ${order.order_date}</p>
        </div>
        
        <div class="invoice-details">
            <h3>Bill To:</h3>
            <p>${order.customer_name}<br>
            ${order.customer_email}<br>
            ${order.customer_address}</p>
        </div>
        
        <table class="items-table">
            <thead>
                <tr>
                    <th>Item</th>
                    <th>Quantity</th>
                    <th>Price</th>
                    <th>Total</th>
                </tr>
            </thead>
            <tbody>
                ${order.items.map(item => `
                    <tr>
                        <td>${item.name}</td>
                        <td>${item.quantity}</td>
                        <td>$${item.price}</td>
                        <td>$${item.quantity * item.price}</td>
                    </tr>
                `).join('')}
            </tbody>
        </table>
        
        <div class="total">
            <p>Total: $${order.total}</p>
        </div>
    </body>
    </html>
  `;
  
  htmlTemplates.push({
    json: {
      html_content: html,
      customer_email: order.customer_email,
      order_number: order.order_number
    }
  });
}

return htmlTemplates;

2. Multi-Source Report Generation

Workflow: Multiple APIs → Data Processing → PDF → Distribution

Setup:

HTTP Request nodes: Fetch data from multiple sources
Merge node: Combine data from different sources
Code node: Process and format data
HTTP Request node: Generate PDF report
Split node: Distribute to multiple channels

3. Conditional PDF Processing

Workflow: Data Input → Conditions → Different PDF Types

Setup:

Trigger node: Receive data
IF node: Check conditions (order amount, customer type, etc.)
HTTP Request nodes: Generate different PDF types based on conditions
Merge node: Combine results
Output nodes: Send to appropriate destinations

Advanced n8n Configurations

Error Handling and Retries

Configure robust error handling:

HTTP Request node: Set retry options
IF node: Check for errors in response
Code node: Handle different error types
HTTP Request node: Retry with different parameters
Gmail node: Send error notifications

Batch Processing

Process multiple documents efficiently:

Code node: Split large datasets into batches
Loop node: Process each batch
HTTP Request node: Generate PDFs
Merge node: Combine results
Output node: Save or send batch results

Real-World n8n + FileSlap Use Cases

E-commerce Automation

Order Processing: Generate invoices, receipts, and shipping labels
Customer Communications: Create personalized welcome packets
Inventory Reports: Daily/weekly inventory summaries
Sales Analytics: Convert dashboard data to printable reports

Content Management

Blog Archives: Convert blog posts to PDF for offline reading
Newsletter Compilations: Monthly newsletter summaries
Documentation: Convert markdown to PDF for distribution
Social Media Reports: Analytics and performance summaries

Business Operations

Financial Reports: Monthly/quarterly financial summaries
HR Documentation: Employee handbooks, policies, and forms
Project Reports: Status updates and milestone summaries
Meeting Minutes: Convert notes to formal PDF documents

Customer Service

Support Tickets: Generate ticket summaries and resolutions
Knowledge Base: Convert help articles to PDF guides
Customer Onboarding: Welcome packets and setup guides
Feedback Reports: Customer survey results and analysis

Performance Optimization

1. Parallel Processing

Use n8n's parallel execution capabilities:

Split node: Divide work into parallel streams
HTTP Request nodes: Process multiple PDFs simultaneously
Merge node: Combine results when complete

2. Caching Strategies

Implement caching for frequently used templates:

Code node: Check cache for existing templates
IF node: Use cached version or generate new
HTTP Request node: Generate only when needed

3. Rate Limiting

Handle API rate limits gracefully:

Code node: Implement delays between requests
Queue node: Process requests in order
Error handling: Retry with exponential backoff

Advanced Data Transformation

Database Integration

Connect directly to your databases:

// PostgreSQL/MySQL query results to HTML
const records = $input.all();
const html = `
  <!DOCTYPE html>
  <html>
  <head>
    <title>Database Report</title>
    <style>
      table { width: 100%; border-collapse: collapse; }
      th, td { border: 1px solid #ddd; padding: 8px; }
      th { background-color: #f2f2f2; }
    </style>
  </head>
  <body>
    <h1>Database Report</h1>
    <table>
      <thead>
        <tr>
          ${Object.keys(records[0].json).map(key => `<th>${key}</th>`).join('')}
        </tr>
      </thead>
      <tbody>
        ${records.map(record => `
          <tr>
            ${Object.values(record.json).map(value => `<td>${value}</td>`).join('')}
          </tr>
        `).join('')}
      </tbody>
    </table>
  </body>
  </html>
`;

return [{ json: { html_content: html } }];

API Data Aggregation

Combine data from multiple APIs:

// Combine data from multiple sources
const salesData = $('Sales API').all();
const customerData = $('Customer API').all();
const inventoryData = $('Inventory API').all();

// Create comprehensive report
const html = `
  <!DOCTYPE html>
  <html>
  <head>
    <title>Comprehensive Business Report</title>
    <style>
      .section { margin: 20px 0; padding: 15px; border: 1px solid #ddd; }
      .metric { display: inline-block; margin: 10px; padding: 10px; background: #f8f9fa; }
    </style>
  </head>
  <body>
    <h1>Business Report - ${new Date().toLocaleDateString()}</h1>
    
    <div class="section">
      <h2>Sales Summary</h2>
      <div class="metric">Total Sales: $${salesData.reduce((sum, item) => sum + item.json.amount, 0)}</div>
      <div class="metric">Orders: ${salesData.length}</div>
    </div>
    
    <div class="section">
      <h2>Customer Overview</h2>
      <div class="metric">Active Customers: ${customerData.length}</div>
      <div class="metric">New This Month: ${customerData.filter(c => c.json.created_this_month).length}</div>
    </div>
    
    <div class="section">
      <h2>Inventory Status</h2>
      <div class="metric">Low Stock Items: ${inventoryData.filter(i => i.json.quantity < 10).length}</div>
      <div class="metric">Total SKUs: ${inventoryData.length}</div>
    </div>
  </body>
  </html>
`;

return [{ json: { html_content: html } }];

Monitoring and Debugging

Workflow Monitoring

n8n Execution Logs: Monitor workflow performance
HTTP Request Response: Check API call success/failure
Error Handling: Capture and log errors
Performance Metrics: Track execution times

Debugging Tips

Test with Sample Data: Use small datasets for testing
Validate HTML: Check HTML structure before API calls
Monitor API Usage: Track conversion counts and limits
Error Notifications: Set up alerts for workflow failures

Security Best Practices

API Key Management

Environment Variables: Store API keys securely
Access Control: Limit API key permissions
Rotation: Regularly rotate API keys
Monitoring: Track API key usage

Data Protection

Input Validation: Validate all input data
Output Sanitization: Clean output before PDF generation
Access Logging: Log all PDF generation requests
Secure Storage: Store PDFs in secure locations

Get Started Today

Ready to build powerful PDF automation workflows?

Sign up at fileslap.com
Get your API key from the dashboard
Install n8n (self-hosted or cloud)
Create your first workflow using the HTTP Request node
Test with simple HTML before building complex workflows

n8n + FileSlap = Unlimited automation possibilities for professional PDF generation.

Need Help?

Documentation: fileslap.com/docs
n8n Community: Join the n8n Discord for workflow help
API Reference: Complete API documentation with examples
Support: Reach out to our team for custom integration help

Transform your data into professional PDFs with the power of n8n automation and FileSlap's cloud-based API.

Tags: #n8n #Automation #PDF #API #Workflow #SelfHosted #FileSlap #Integration