Converting a doc Node.js buffer into pdf file to output it into the client

Question

I have a docx Node.js buffer.

var buf = doc.getZip()
             .generate({type: 'nodebuffer'});

console.log("buffer is ", buf);

I am getting the buffer like

<Buffer 50 4b 03 04 0a 00 00 00 00 00 42 42 3d 4d 23 df 99 8f 65 05 00 00 65 05 00 00 13 00 00 00 5b 43 6f 6e 74 65 6e 74 5f 54 79 70 65 73 5d 2e 78 6d 6c 3c ... >

I want it to get converted to a pdf document and download it in the client side. I don't want the document to be saved into the server side.

I have one solution i.e to convert docx buffer into docx file and then the docx file into pdf.

fs.writeFileSync(path.resolve(__dirname, 'output.docx'), buf);
docToPdf('./output.docx').then(
   console.log("it is done")
)

But, in this way, the document gets saved in the server. And docToPdf is also using LibreOffice. Is there any better way in which I can avoid all this.

Answer 1

https://www.npmjs.com/package/@nativedocuments/docx-wasm (which is new as I write, Jan 2019) will do what you want.

const fs = require('fs');
const docx = require("@nativedocuments/docx-wasm");

// init docx engine
docx.init({
    // ND_DEV_ID: "XXXXXXXXXXXXXXXXXXXXXXXXXX",    // goto https://developers.nativedocuments.com/ to get a dev-id/dev-secret
    // ND_DEV_SECRET: "YYYYYYYYYYYYYYYYYYYYYYYYYY", // you can also set the credentials in the enviroment variables
    ENVIRONMENT: "NODE", // required
    LAZY_INIT: true      // if set to false the WASM engine will be initialized right now, usefull pre-caching (like e.g. for AWS lambda)
}).catch( function(e) {
    console.error(e);
});

async function convertHelper(document, exportFct) {
    const api = await docx.engine();
    await api.load(document);
    const arrayBuffer = await api[exportFct]();
    await api.close();
    return arrayBuffer;
}

convertHelper("sample.docx", "exportPDF").then((arrayBuffer) => {
    fs.writeFileSync("sample.pdf", new Uint8Array(arrayBuffer));
}).catch((e) => {
    console.error(e);
});

As you can see from the above, you'll need an API key (its freemium model). Disclosure: I have an interest in this.