File Attachments

API triggers support file attachments using multipart/form-data. Attachments are stored in S3 and made available to your workflow via signed URLs in the inputs.

Supported Content Types

API triggers support the following content types:

application/json: JSON payload with structured data
application/x-www-form-urlencoded: Form-encoded data (key-value pairs)
multipart/form-data: Form data with file attachments (API triggers only)

Note: Webhook triggers support JSON and form-encoded data only. File attachments are not supported for webhook triggers.

Limits

Maximum 25MB per file
Maximum 100MB total across all attachments
Maximum 20 files per request
Executable files and scripts are blocked for security

Example Requests

Single File Attachment

curl --location 'https://triggers.app.pinkfish.ai/ext/triggers/YOUR_WORKFLOW_ID' \
--header 'X-API-KEY: YOUR_API_KEY' \
--form 'description="Process this document"' \
--form 'file=@"/path/to/document.pdf"'

Multiple File Attachments

curl --location 'https://triggers.app.pinkfish.ai/ext/triggers/YOUR_WORKFLOW_ID' \
--header 'X-API-KEY: YOUR_API_KEY' \
--form 'action="process"' \
--form 'files=@"/path/to/file1.pdf"' \
--form 'files=@"/path/to/file2.jpg"' \
--form 'metadata="{\"priority\": \"high\"}"'

Using JavaScript/Node.js

const FormData = require('form-data');
const fs = require('fs');

const form = new FormData();
form.append('description', 'Process this document');
form.append('file', fs.createReadStream('/path/to/document.pdf'));

const response = await fetch('https://triggers.app.pinkfish.ai/ext/triggers/YOUR_WORKFLOW_ID', {
  method: 'POST',
  headers: {
    'X-API-KEY': 'YOUR_API_KEY',
    ...form.getHeaders()
  },
  body: form
});

Using Python

import requests

url = 'https://triggers.app.pinkfish.ai/ext/triggers/YOUR_WORKFLOW_ID'
headers = {'X-API-KEY': 'YOUR_API_KEY'}

files = [
    ('file', ('document.pdf', open('/path/to/document.pdf', 'rb'), 'application/pdf'))
]
data = {'description': 'Process this document'}

response = requests.post(url, headers=headers, files=files, data=data)

Accessing Attachments in Your Workflow

Attachments are available in your workflow inputs as an array. Each attachment includes:

filename: The sanitized filename (path components removed, special characters sanitized)
contentType: The MIME type of the file
size: File size in bytes
url: A signed URL to download the file from S3 (valid for 24 hours)

Example Inputs Structure

{
  "description": "Process this document",
  "attachments": [
    {
      "filename": "document.pdf",
      "contentType": "application/pdf",
      "size": 245678,
      "url": "https://s3.amazonaws.com/..."
    }
  ]
}

Using Attachments in Code Steps

You can access attachments in your workflow code:

// Get the first attachment URL
const attachmentUrl = @workflow.inputs.attachments[0].url;

// Download the file
const response = await fetch(attachmentUrl);
const fileData = await response.arrayBuffer();

// Process the file
// ...

Using Attachments with Slash Commands

You can pass attachment URLs directly to slash commands that accept file URLs:

// Pass attachment URL to PDF processing
const pdfUrl = @workflow.inputs.attachments[0].url;
// Use /pdf-to-text with the URL

Security Considerations

Executable files (.exe, .sh, .bat, etc.) are automatically blocked
Filenames are sanitized to prevent path traversal attacks
Files are stored in isolated S3 buckets per run
Signed URLs expire after 24 hours
File size limits prevent abuse

Troubleshooting

”Too many attachments” Error

You’ve exceeded the 20 file limit. Split your request into multiple API calls.

”File too large” Error

Individual files cannot exceed 25MB. Compress or split large files before uploading.

”Total attachment size exceeds limit” Error

The combined size of all attachments exceeds 100MB. Reduce the number or size of files.

”Blocked file type” Error

The file type you’re trying to upload is blocked for security reasons. Executable files and scripts are not allowed.

Attachments Not Appearing in Workflow

Ensure you’re using multipart/form-data content type
Check that you’re using an API trigger (not a webhook trigger)
Verify the files were uploaded successfully (check the run inputs in the Runs Monitor)

API Documentation