Exporting only a specific set of pages in Node with Unfetch

In this guide, we'll show you how to export only a specific set of pages from a document using Node and the Unfetch library to convert them to PDF using PDFShift's API.

When you're converting a document, you might want to export only a specific set of pages from a document. This can be done by setting the pages parameter to the request.

It behaves exactly like the page parameter you can see when you print a document from your browser.

It accepts the following pattern:

• A number, such as 2. This will print the page 2
• A range, such as 2-4. This will print the pages 2 to 4 (2, 3 and 4)
• A list, such as 2,4,5,9. This will print the pages 2, 4, 5 and 9

This way, you can only export the pages that you really need and get immediately the result you want in the PDF, without having to edit it.

Here's an example:

const fetch = require('unfetch')
const fs = require('fs');

// You can get an API key at https://pdfshift.io
api_key = 'sk_xxxxxxxxxxxx'

params = {
    source: 'https://en.wikipedia.org/wiki/PDF',
    pages: '2-4'
}

const response = await fetch('https://api.pdfshift.io/v3/convert/pdf', {
    method: 'POST',
    headers: {
        'Content-Type': 'application/json',
        'Authorization': `Basic ${Buffer.from(`api:${api_key}`).toString('base64')}`
    },
    body: JSON.stringify(params)
})

// Handle errors:
if (!response.ok) {
    throw new Error(`Request failed with status code ${response.status}: ${response.data}`);
}

fs.writeFileSync('result.pdf', await response.blob());

console.log('The PDF document was generated and saved to result.pdf');