---
title: "Node.js large document triage"
canonical_url: "https://www.nutrient.io/guides/dws-viewer/examples/nodejs-large-document-triage/"
md_url: "https://www.nutrient.io/guides/dws-viewer/examples/nodejs-large-document-triage.md"
last_updated: "2026-06-10T14:59:56.779Z"
description: "Upload a document to DWS Viewer API and collect a support-ready triage packet with metadata, text/search checks, and a rendered first-page preview."
---

# Node.js large document triage

This example automates a support-oriented triage workflow for large documents.

The script:

1. Uploads a local file

2. Extracts the returned `document_id`

3. Fetches `document_info`

4. Fetches `properties`

5. Fetches text from page 0

6. Optionally runs a search query

7. Renders page 0 as a PNG preview

8. Saves all outputs to disk

## Prerequisites

- A DWS Viewer API key in `NUTRIENT_DWS_VIEWER_API_KEY`

- Node.js 18 or later

- A local input file

## Complete example

The following script can be run with `node` and accepts command-line arguments for the input file path, MIME type, and an optional search query:

```js

import { mkdir, readFile, writeFile } from "node:fs/promises";
import path from "node:path";

const apiKey = process.env.NUTRIENT_DWS_VIEWER_API_KEY;
const inputPath = process.argv[2];
const mimeType = process.argv[3]?? "application/pdf";
const searchQuery = process.argv[4]?? "";

if (!apiKey) {
  throw new Error("Missing NUTRIENT_DWS_VIEWER_API_KEY");
}

if (!inputPath) {
  throw new Error(
    "Usage: node triage.mjs <inputPath> [mimeType] [optionalSearchQuery]",
  );
}

const fileBuffer = await readFile(inputPath);

const uploadResponse = await fetch("https://api.nutrient.io/viewer/documents", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${apiKey}`,
    "Content-Type": mimeType,
    "Content-Length": fileBuffer.length.toString(),
  },
  body: fileBuffer,
});

if (!uploadResponse.ok) {
  const errorText = await uploadResponse.text();
  throw new Error(`Upload failed: ${uploadResponse.status} ${errorText}`);
}

const uploadResult = await uploadResponse.json();
const documentId = uploadResult.data?.document_id;

if (!documentId) {
  throw new Error("No document_id found in upload response");
}

const outputDir = path.resolve(`./dws-triage-${documentId}`);
await mkdir(outputDir, { recursive: true });

const requestJson = async (pathname) => {
  const response = await fetch(`https://api.nutrient.io${pathname}`, {
    headers: {
      Authorization: `Bearer ${apiKey}`,
      Accept: "application/json",
    },
  });

  if (!response.ok) {
    const errorText = await response.text();
    throw new Error(`${pathname} failed: ${response.status} ${errorText}`);
  }

  return response.json();
};

const requestBinary = async (pathname, accept) => {
  const response = await fetch(`https://api.nutrient.io${pathname}`, {
    headers: {
      Authorization: `Bearer ${apiKey}`,
      Accept: accept,
    },
  });

  if (!response.ok) {
    const errorText = await response.text();
    throw new Error(`${pathname} failed: ${response.status} ${errorText}`);
  }

  return Buffer.from(await response.arrayBuffer());
};

const documentInfo = await requestJson(
  `/viewer/documents/${documentId}/document_info`,
);
const documentProperties = await requestJson(
  `/viewer/documents/${documentId}/properties`,
);
const firstPageText = await requestJson(
  `/viewer/documents/${documentId}/pages/0/text`,
);

let searchResults = null;
if (searchQuery) {
  const params = new URLSearchParams({ q: searchQuery });
  searchResults = await requestJson(
    `/viewer/documents/${documentId}/search?${params.toString()}`,
  );
}

const previewImage = await requestBinary(
  `/viewer/documents/${documentId}/pages/0/image?width=1600`,
  "image/png",
);

await Promise.all([
  writeFile(
    path.join(outputDir, "upload-response.json"),
    JSON.stringify(uploadResult, null, 2),
  ),
  writeFile(
    path.join(outputDir, "document-info.json"),
    JSON.stringify(documentInfo, null, 2),
  ),
  writeFile(
    path.join(outputDir, "document-properties.json"),
    JSON.stringify(documentProperties, null, 2),
  ),
  writeFile(
    path.join(outputDir, "page-0-text.json"),
    JSON.stringify(firstPageText, null, 2),
  ),
  writeFile(path.join(outputDir, "page-0.png"), previewImage),
]);

if (searchResults) {
  await writeFile(
    path.join(outputDir, "search-results.json"),
    JSON.stringify(searchResults, null, 2),
  );
}

console.log(`Saved triage packet to ${outputDir}`);
console.log(`document_id: ${documentId}`);

```

## Run the script

Run the script with the required environment variable and command-line arguments — for example:

```shell

export NUTRIENT_DWS_VIEWER_API_KEY=your_api_key_here
node triage.mjs./large-document.pdf application/pdf invoice

```

Example output directory:

```text./dws-triage-<document_id>/
├── document-info.json
├── document-properties.json
├── page-0-text.json
├── page-0.png
├── search-results.json
└── upload-response.json

```

If you don’t want to run a search check, omit the final argument.

## What this packet helps you validate

Whether:

- The upload succeeded and returned the expected `document_id`

- The document metadata and properties look reasonable

- Page 0 exposes usable extracted text

- A representative term can be found with search

- The first page renders correctly as a server-generated image

## Related guides

- [Large document triage](https://www.nutrient.io/guides/dws-viewer/troubleshooting/large-document-triage.md)

- [Support](https://www.nutrient.io/guides/dws-viewer/support.md)
---

## Related pages

- [Examples](/guides/dws-viewer/examples.md)
- [Node.js integration example](/guides/dws-viewer/examples/nodejs-integration-example.md)
- [Node.js rendering and font diagnostics](/guides/dws-viewer/examples/nodejs-rendering-font-diagnostics.md)
- [Build secure PDF viewers with table extraction functionality](/guides/dws-viewer/examples/build-secure-pdf-viewers-with-table-extraction.md)