WebAssembly API

Package

npm: edgeparse-wasm · Source: crates/edgeparse-wasm/

Initialization

Before calling any conversion function, initialize the WASM module:

import init from 'edgeparse-wasm';

// Async initialization — fetches and compiles the .wasm binary
await init();

Call init() once at application startup. Subsequent calls are no-ops.

convert()

Parses PDF bytes and returns a structured JavaScript object representing the full document.

function convert(
  pdf_bytes: Uint8Array,
  format?: string | null,
  pages?: string | null,
  reading_order?: string | null,
  table_method?: string | null,
): any;

Parameters

Parameter	Type	Default	Description
pdf_bytes	Uint8Array	(required)	Raw PDF file bytes
format	string | null	"json"	Output format hint: "json", "markdown", "html", "text"
pages	string | null	"all"	Page range: "all", "1-5", "1,3,7"
reading_order	string | null	"auto"	Reading order algorithm: "auto" (XY-Cut++) or "off"
table_method	string | null	"default"	Table detection: "default" (ruling lines) or "cluster" (borderless)

Return value

A JavaScript object representing the Rust PdfDocument struct, serialized via serde_wasm_bindgen. The top-level document has a kids array containing ContentElement enum variants (externally-tagged):

{
  file_name: string,
  number_of_pages: number,
  author: string | null,
  title: string | null,
  kids: Array<Record<string, any>>  // externally-tagged Rust enum variants
}

Each element in kids is an externally-tagged enum object like { "Paragraph": { ... } } or { "Heading": { ... } }. For most use cases, convert_to_string(bytes, 'json') + JSON.parse() is simpler and gives the same structured schema as the Python/Node.js SDK.

Example

import init, { convert_to_string } from 'edgeparse-wasm';

await init();

const bytes = new Uint8Array(await file.arrayBuffer());

// Easiest: parse JSON string — same schema as Python/Node.js SDK
const doc = JSON.parse(convert_to_string(bytes, 'json'));

// Iterate elements (uses same keys as Python/Node.js JSON output)
for (const el of doc.kids) {
  if (el.type === 'table') {
    console.log('Table found on page', el['page number']);
  }
}

convert_to_string()

Parses PDF bytes and returns a formatted string.

function convert_to_string(
  pdf_bytes: Uint8Array,
  format?: string | null,
  pages?: string | null,
  reading_order?: string | null,
  table_method?: string | null,
): string;

Parameters

Same as convert().

Return value

A string in the requested format:

Format	Output
"json"	JSON string with bounding boxes and element types
"markdown"	Standard Markdown with GFM tables
"html"	HTML5 with semantic elements
"text"	Plain UTF-8 text with reading order preserved

Example

import init, { convert_to_string } from 'edgeparse-wasm';

await init();

const bytes = new Uint8Array(await file.arrayBuffer());

const markdown = convert_to_string(bytes, 'markdown');
const html = convert_to_string(bytes, 'html');
const text = convert_to_string(bytes, 'text');
const json = convert_to_string(bytes, 'json');

version()

Returns the EdgeParse version string.

function version(): string;

Example

import { version } from 'edgeparse-wasm';
console.log(version()); // "0.2.3"

Error handling

Both convert() and convert_to_string() throw JsError on failure (corrupted PDF, invalid page range, etc.):

try {
  const markdown = convert_to_string(bytes, 'markdown');
} catch (err) {
  console.error('PDF parsing failed:', err.message);
}

Browser compatibility

Browser	Minimum version
Chrome	57+
Firefox	52+
Safari	11+
Edge	16+

Requires WebAssembly and ES module support. The build.target: 'esnext' setting in Vite/Webpack ensures compatibility.

TypeScript support

Full .d.ts type definitions ship with the package. Your IDE will provide autocomplete and type checking automatically.

Live demo

Try the interactive demo: edgeparse.com/demo/