Social Media Automation (n8n)

# Social Media Automation (n8n)

An automated workflow that manages dual-platform social media posting from a Google Sheets content database. Built on n8n, this workflow eliminates manual posting while ensuring content quality through pre-publish validation.

Workflow Architecture

Workflow Nodes

Data Flow

Input: Google Sheet Structure

Processing Pipeline

API Integration Details

Facebook Graph API

// Node: 📘 Facebook Post
{
  method: "POST",
  node: facebook_page_id,  // From sheet: facebook_id
  edge: "photos",
  query: {
    message: facebook_caption,
    url: image_url,
    published: "true"
  }
}

Instagram Graph API (Two-Step)

// Step 1: Create Media Container
// Node: 📷 Instagram Container
{
  method: "POST",
  node: instagram_id,  // From sheet: instagram_id
  edge: "media",
  query: {
    image_url: image_url,
    caption: instagram_caption
  }
}
// Returns: container_id

// Step 2: Publish Container (after status = FINISHED)
// Node: 📤 Publish Instagram
{
  method: "POST",
  node: instagram_id,
  edge: "media_publish",
  query: {
    creation_id: container_id
  }
}
// Returns: instagram_post_id

Image Validation

// Node: 🔍 Validate Image URL
{
  method: "HEAD",
  url: image_url,
  options: {
    timeout: 5000,
    redirect: { maxRedirects: 5 }
  }
}

// Validation: ✅ Image Valids?
{
  conditions: [
    statusCode == 200,
    content-type == "image/jpeg" OR "image/png"
  ]
}

Error Handling

Validation Failure Path

🔍 Validate Image URL 
    ↓ (failed)
⚠️ Validation Error Alert → Telegram notification
    ↓
📝 Mark Validation Failed → Update sheet: status='validation_failed'

Instagram Processing Retry

⏰ Initial Processing Wait (wait for media processing)
    ↓
🔍 Check Instagram Status → GET /{container_id}?fields=status_code
    ↓
✅ Is Instagram Ready?
    ├── YES → 📤 Publish Instagram
    └── NO  → ⏰ Retry Wait Loop → Check again (loop)

Error Workflow

The workflow is configured with an error workflow for handling unexpected failures:

• Error Workflow ID: j44unWD08cU7Buhc
• Caller Policy: Workflows from same owner only

Telegram Notifications

Success Notification

✅ Post Successfully Published

📱 Instagram: Published with ID: {instagram_post_id}
📘 Facebook: Published with ID: {facebook_post_id}

📄 Caption: {caption.substring(0, 100)}...

🖼️ Image: {image_url}

✅ Status: {statusCode} : {statusMessage}

⏰ Time: {current_timestamp}

Validation Failure Alert

❌ Image Validation Failed

🚫 Issue: Image URL is not accessible or invalid

🖼️ URL: {image_url}

📄 Caption: {caption.substring(0, 100)}...

⚠️ Action Required: Please check and update the image URL in the spreadsheet.

🚫 Status: {statusCode} : {statusMessage}

⏰ Time: {current_timestamp}

Configuration

Credentials

Schedule Settings

Key Design Decisions

Why Single Post Per Run?

Processing one post per execution ensures:

• Idempotency: Easy to retry on failure without complex state management
• Rate Limiting: Respects Meta API limits
• Error Isolation: One failure doesn't block subsequent posts
• Auditability: Each post can be tracked individually

Why Two-Step Instagram Posting?

Instagram's API requires:

1. Create container → Get container_id
2. Wait for processing → Check status
3. Publish container → Get post_id

This asynchronous design prevents the workflow from blocking while Meta processes media.

Why Image Validation?

Pre-validating image URLs prevents:

• Failed posts that waste API quota
• Broken images on social platforms
• User confusion when posts silently fail

Why Telegram Notifications?

Immediate visibility into:

• Successful posts (confirmation)
• Failed validations (action required)
• API errors (debugging)

Use Cases

This workflow powers content scheduling for social media campaigns:

1. Content Calendar: Team populates Google Sheet with planned posts
2. Approval Workflow: Mark posts as "pending" when ready to publish
3. Automated Publishing: Workflow runs daily, picks up pending content
4. Cross-Platform Sync: Single entry posts to both Facebook and Instagram
5. Audit Trail: Post IDs tracked in sheet for performance monitoring

Scalability Considerations

Portfolio Context

This n8n workflow demonstrates:

• Low-code automation for business processes
• Multi-platform API integration (Facebook, Instagram, Google, Telegram)
• Error handling with retry logic and notifications
• Workflow design for production reliability