pdf-tax-reader-cl

A Node.js library for extracting specific data from Chilean tax PDF documents. This library is designed to scrape structured PDF documents like "CARPETA TRIBUTARIA ELECTRÓNICA PARA SOLICITAR CRÉDITOS" and extract key information.

🚀 Quick Start

npm install pdf-tax-reader-cl

const { extractTaxData } = require('pdf-tax-reader-cl');

// Extract data from a PDF file
extractTaxData('./tax-document.pdf')
  .then(data => {
    console.log('Extracted Data:', data);
    // {
    //   emitterName: "GUITAL Y PARTNERS LIMITADA",
    //   economicActivities: [
    //     "ASES.COMER.PUBLICIDAD,REPONEDORES,COMERC.FRUT,VERD,BEBIDAS DE FANTASIA",
    //     "463011     VENTA AL POR MAYOR DE FRUTAS Y VERDURAS"
    //   ],
    //   address: "VITACURA 4380 , Dpto. 31 , VITACURA"
    // }
  })
  .catch(error => {
    console.error('Error:', error.message);
  });

Features

• Extract emitter name from PDF documents
• Extract economic activities list
• Extract address information
• Process single PDF files or entire directories
• Save extracted data to JSON format
• Comprehensive error handling and logging

Installation

npm install pdf-tax-reader-cl

Requirements

• Node.js >= 14.0.0
• PDF files must be text-based (not scanned images)
• PDFs must follow the Chilean tax document structure

Usage

Single PDF Processing

const { extractTaxData } = require('pdf-tax-reader-cl');

// Process a single PDF file
extractTaxData('./documents/tax-document.pdf')
  .then(data => {
    console.log('Extracted Data:', data);
  })
  .catch(error => {
    console.error('Error:', error.message);
  });

Multiple PDF Processing

const { processMultiplePDFs } = require('pdf-tax-reader-cl');

// Process all PDF files in a directory
processMultiplePDFs('./documents')
  .then(results => {
    console.log('Processing completed:', results);
    // [
    //   {
    //     filename: "document1.pdf",
    //     data: { emitterName: "...", economicActivities: [...], address: "..." }
    //   },
    //   {
    //     filename: "document2.pdf",
    //     error: "Invalid PDF format"
    //   }
    // ]
  })
  .catch(error => {
    console.error('Error:', error);
  });

TypeScript Support

import { extractTaxData, ExtractedTaxData } from 'pdf-tax-reader-cl';

// Extract data with TypeScript types
extractTaxData('./path/to/document.pdf')
  .then((data: ExtractedTaxData) => {
    console.log('Extracted Data:', data);
    // data.emitterName is string | null
    // data.economicActivities is string[]
    // data.address is string | null
  })
  .catch(error => {
    console.error('Error:', error);
  });

Testing

If you're developing or contributing to this library:

# Clone the repository
git clone https://github.com/Jmzp/pdf-tax-reader-cl.git
cd pdf-tax-reader-cl

# Install dependencies
npm install

# Run tests
npm test

The test suite includes:

• Mock data validation
• Single PDF processing test
• Multiple PDF processing test

Error Handling Examples

The application provides detailed error messages for different types of invalid files:

// Example error handling
try {
    const data = await extractTaxData('./invalid-file.txt');
} catch (error) {
    console.log('Error:', error.message);
    // Output: "Invalid file extension. Expected .pdf, got: txt"
}

try {
    const data = await extractTaxData('./corrupted-file.pdf');
} catch (error) {
    console.log('Error:', error.message);
    // Output: "Invalid PDF format. File does not appear to be a valid PDF document."
}

try {
    const data = await extractTaxData('./non-tax-document.pdf');
} catch (error) {
    console.log('Error:', error.message);
    // Output: "Document does not appear to be a Chilean tax document. Missing expected tax document structure."
}

Data Extraction

The application extracts the following information from PDF documents:

1. Emitter Name (Nombre del emisor)

• Extracts the company or entity name that generated the document
• Pattern: Nombre del emisor: [COMPANY_NAME]

2. Economic Activities (Actividades Económicas)

• Extracts all economic activities listed in the document
• Includes both general descriptions and specific activity codes
• Pattern: Looks for lines containing activity codes (6 digits) or specific keywords

3. Address (Domicilio)

• Extracts the registered address of the taxpayer
• Pattern: Domicilio: [ADDRESS]

Output Format

The extracted data is returned in the following JSON format:

{
  "emitterName": "GUITAL Y PARTNERS LIMITADA",
  "economicActivities": [
    "ASES.COMER.PUBLICIDAD, REPONEDORES, COMERC.FRUT, VERD, BEBIDAS DE FANTASIA",
    "463011 VENTA AL POR MAYOR DE FRUTAS Y VERDURAS",
    "463020 VENTA AL POR MAYOR DE BEBIDAS ALCOHOLICAS Y NO ALCOHOLICAS",
    "692000 ACTIVIDADES DE CONTABILIDAD, TENEDURIA DE LIBROS Y AUDITORIA; CONSULTO",
    "731001 SERVICIOS DE PUBLICIDAD PRESTADOS POR EMPRESAS",
    "783000 OTRAS ACTIVIDADES DE DOTACION DE RECURSOS HUMANOS",
    "854909 OTROS TIPOS DE ENSEÑANZA N.C.P.",
    "855000 ACTIVIDADES DE APOYO A LA ENSEÑANZA"
  ],
  "address": "VITACURA 4380, Dpto. 31, VITACURA"
}

API Reference

Functions

extractTaxData(pdfPath: string): Promise<ExtractedTaxData>

Extract tax data from a PDF file.

processMultiplePDFs(directoryPath: string): Promise<ProcessingResult[]>

Process multiple PDF files in a directory.

saveToJSON(data: any, outputPath: string): void

Save extracted data to JSON file.

isValidPDF(dataBuffer: Buffer): boolean

Validate if a file is a valid PDF.

hasValidExtension(filePath: string): boolean

Validate file extension.

isTaxDocument(text: string): boolean

Check if the document appears to be a Chilean tax document.

validateExtractedData(data: ExtractedTaxData): ValidationResult

Validate extracted data completeness.

Types

ExtractedTaxData

interface ExtractedTaxData {
  emitterName: string | null;
  economicActivities: string[];
  address: string | null;
}

ProcessingResult

interface ProcessingResult {
  filename: string;
  data?: ExtractedTaxData;
  error?: string;
}

Dependencies

• pdf-parse: For extracting text content from PDF files
• Built-in Node.js modules: fs, path

Error Handling & Validation

The application includes comprehensive error handling and validation for:

File Validation

• File existence: Checks if the file exists before processing
• File extension: Validates that the file has a .pdf extension
• File size: Ensures the file is not empty
• PDF format: Validates PDF structure and signatures

Content Validation

• PDF structure: Verifies the file is a valid PDF document
• Text content: Ensures the PDF contains extractable text (not just scanned images)
• Tax document structure: Validates that the document appears to be a Chilean tax document
• Data completeness: Ensures all required fields are successfully extracted

Error Types Handled

• File not found errors
• Invalid file extensions (.txt, .doc, etc.)
• Corrupted or invalid PDF files
• Empty files
• PDFs without extractable text
• Non-tax documents
• Incomplete data extraction
• Directory access errors

Limitations

• The application is designed specifically for Chilean tax documents with the structure shown in the example
• PDF must be text-based (not scanned images)
• Extraction accuracy depends on the consistency of the PDF format
• The application will reject non-PDF files, corrupted PDFs, and documents that don't match the expected tax document structure

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add some amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

License

This project is licensed under the MIT License - see the LICENSE file for details.

Author

Jorge Zapata - GitHub

Support

If you find this library useful, please consider giving it a ⭐️ on GitHub!