Type Definitions

Complete reference for all TypeScript interfaces and types exported by undms.

Input Types

Document

Input document interface for extraction.

interface Document {
  name: string;
  size: number;
  type: string;
  lastModified: number;
  webkitRelativePath: string;
  buffer: Buffer;
}

Properties

Property	Type	Description
name	string	File name
size	number	File size in bytes
type	string	MIME type (e.g., text/plain, application/pdf)
lastModified	number	Last modified timestamp (Unix epoch ms)
webkitRelativePath	string	File path for web compatibility
buffer	Buffer	File content as a Buffer

Example

const document: Document = {
  name: 'report.pdf',
  size: 1024,
  type: 'application/pdf',
  lastModified: Date.now(),
  webkitRelativePath: '/documents/report.pdf',
  buffer: Buffer.from(pdfData),
};

---

Output Types

DocumentMetadata

Metadata result for extracted documents.

interface DocumentMetadata {
  name: string;
  size: number;
  processingTime: number;
  encoding: string;
  content: string;
  metadata?: MetadataPayload;
  error?: string;
}

Properties

Property	Type	Description
name	string	Original file name
size	number	File size in bytes
processingTime	number	Extraction time in milliseconds
encoding	string	Detected encoding or MIME type
content	string	Extracted text content
metadata	MetadataPayload	Format-specific metadata (optional)
error	string	Error message if extraction failed (optional)

---

DocumentMetadataWithSimilarity

Document metadata with similarity results.

interface DocumentMetadataWithSimilarity {
  name: string;
  size: number;
  processingTime: number;
  encoding: string;
  content: string;
  metadata?: MetadataPayload;
  error?: string;
  similarityMatches: SimilarityMatch[];
}

Extends DocumentMetadata with similarityMatches.

---

GroupedDocuments

Documents grouped by MIME type.

interface GroupedDocuments {
  mimeType: string;
  documents: DocumentMetadata[];
}

---

GroupedDocumentsWithSimilarity

Grouped documents with similarity data.

interface GroupedDocumentsWithSimilarity {
  mimeType: string;
  documents: DocumentMetadataWithSimilarity[];
}

---

SimilarityMatch

Similarity comparison result.

interface SimilarityMatch {
  referenceIndex: number;
  similarityPercentage: number;
}

Properties

Property	Type	Description
referenceIndex	number	Index into the reference texts array
similarityPercentage	number	Similarity score (0-100)

---

Metadata Types

MetadataPayload

Complete metadata payload with format-specific fields.

interface MetadataPayload {
  text?: TextMetadata;
  docx?: DocxMetadata;
  xlsx?: XlsxMetadata;
  pdf?: PdfMetadata;
  image?: ImageMetadata;
}

Contains one or more format-specific metadata objects depending on the document type.

---

TextMetadata

Text content statistics.

interface TextMetadata {
  lineCount: number;
  wordCount: number;
  characterCount: number;
  nonWhitespaceCharacterCount: number;
}

Properties

Property	Type	Description
lineCount	number	Number of lines
wordCount	number	Total word count
characterCount	number	Total characters including whitespace
nonWhitespaceCharacterCount	number	Characters without whitespace

---

DocxMetadata

DOCX-specific metadata.

interface DocxMetadata {
  paragraphCount: number;
  tableCount: number;
  imageCount: number;
  hyperlinkCount: number;
}

Properties

Property	Type	Description
paragraphCount	number	Total paragraphs
tableCount	number	Number of tables
imageCount	number	Embedded images
hyperlinkCount	number	Hyperlinks in the document

---

XlsxMetadata

XLSX-specific metadata.

interface XlsxMetadata {
  sheetCount: number;
  sheetNames: string[];
  rowCount: number;
  columnCount: number;
  cellCount: number;
}

Properties

Property	Type	Description
sheetCount	number	Number of worksheets
sheetNames	string[]	Names of all sheets
rowCount	number	Total rows across all sheets
columnCount	number	Maximum columns in any sheet
cellCount	number	Total cells with content

---

PdfMetadata

PDF-specific metadata.

interface PdfMetadata {
  title?: string;
  author?: string;
  subject?: string;
  producer?: string;
  pageSize?: PdfPageSize;
  pageCount: number;
}

Properties

Property	Type	Description
title	string	Document title (optional)
author	string	Document author (optional)
subject	string	Document subject (optional)
producer	string	PDF producer application
pageSize	PdfPageSize	First page dimensions
pageCount	number	Total number of pages

---

PdfPageSize

PDF page dimensions.

interface PdfPageSize {
  width: number;
  height: number;
}

---

ImageMetadata

Image-specific metadata.

interface ImageMetadata {
  width: number;
  height: number;
  format?: string;
  cameraMake?: string;
  cameraModel?: string;
  datetimeOriginal?: string;
  location: ImageLocation;
}

Properties

Property	Type	Description
width	number	Image width in pixels
height	number	Image height in pixels
format	string	Image format (JPEG, PNG, etc.)
cameraMake	string	Camera manufacturer
cameraModel	string	Camera model
datetimeOriginal	string	Date/time when photo was taken
location	ImageLocation	GPS coordinates

---

ImageLocation

GPS coordinates from EXIF data.

interface ImageLocation {
  latitude?: number;
  longitude?: number;
}

---

Type Aliases

SimilarityMethod

Valid similarity algorithms.

type SimilarityMethod = 'jaccard' | 'ngram' | 'levenshtein' | 'hybrid';

---

Complete Usage Example

import { extract, computeDocumentSimilarity, computeTextSimilarity } from 'undms';

const documents: Document[] = [
  {
    name: 'report.txt',
    size: 1024,
    type: 'text/plain',
    lastModified: Date.now(),
    webkitRelativePath: '',
    buffer: Buffer.from('Sample content'),
  },
];

// Extract
const extractResults = extract(documents);
const extractedDoc: DocumentMetadata = extractResults[0].documents[0];

// Access metadata
if (extractedDoc.metadata?.text) {
  const textMeta: TextMetadata = extractedDoc.metadata.text;
  console.log(textMeta.wordCount);
}

// Compute document similarity
const similarityResults = computeDocumentSimilarity(documents, ['reference text'], 50, 'hybrid');
const docWithSimilarity: DocumentMetadataWithSimilarity = similarityResults[0].documents[0];

docWithSimilarity.similarityMatches.forEach((match: SimilarityMatch) => {
  console.log(match.referenceIndex, match.similarityPercentage);
});

// Compute text similarity
const textMatches = computeTextSimilarity('source text', ['reference'], 30, 'hybrid');