You can use Aspose.Slides Cloud SDK for Node.js to convert presentations to PDF, PNG, and many other formats. The following code example shows you how to convert a PowerPoint presentation to a PDF document using Aspose.Slides Cloud:

const cloud = require("asposeslidescloud")
const fs = require("fs")

const slidesApi = new cloud.SlidesApi("client_id", "client_secret")

const fileStream = fs.createReadStream("example.pptx")

// Convert the presentation to a PDF document.
slidesApi.convert(fileStream, "pdf").then((response) => {

    // Save the PDF document to a file.
    fs.writeFile("output.pdf", response.body, (error) => {
        if (error) throw error
    })
})

This is a paid product, but you can make 150 free API calls per month for presentation conversions and other purposes. It provides a REST-based API for managing presentations. I work as a Support Developer at Aspose.