The Custom Document Loader provides the ability to create custom document loading functionality using JavaScript. This module enables flexible and customized document processing through user-defined functions.
This module provides a flexible document loader that can:
* Execute custom JavaScript functions for document loading
* Handle input variables dynamically
* Support both document and text outputs
* Run in a sandboxed environment
* Access flow context and variables
* Process custom metadata
## Inputs
### Required Parameters
* **Javascript Function**: Custom code that returns either:
* Array of document objects (for Document output)
* String (for Text output)
### Optional Parameters
* **Input Variables**: JSON object containing variables accessible in the function with $ prefix
## Outputs
* **Document**: Array of document objects containing metadata and pageContent
* **Text**: Concatenated string from pageContent of documents
## Features
* Sandboxed execution environment
* Variable injection support
* Flow context access
* Custom dependency support
* Error handling
* Timeout protection
* Input validation
## Document Structure
When returning documents, each object must have:
```javascript
{
pageContent: 'Document Content',
metadata: {
title: 'Document Title',
// ... other metadata
}
}
```
## Example Usage
### Document Output
```javascript
return [
{
pageContent: 'Document Content',
metadata: {
title: 'Document Title',
source: 'Custom Source'
}
}
]
```
### Text Output
```javascript
return "Processed text content"
```
## Available Context
* **$input**: Input value passed to the function
* **$vars**: Access to flow variables
* **$flow**: Flow context object containing:
* chatflowId
* sessionId
* chatId
* input
## Notes
* Functions run in a secure sandbox
* 10-second execution timeout
* Built-in dependencies available
* External dependencies configurable
* Input variables must be valid JSON
* Error handling for invalid returns
* Supports async operations
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