Generate & email pdf in Cloud Functions using Node.js and Firebase cloudstore

Question

I have the following code in cloud functions that triggers whenever the user make an order. Then I want to generate an invoice in pdf using firebase storage and then email the pdf to the user. I have a hard time to get the pdf generate as I am not sure exactly how I should be doing it. The email gets send with no problem to the user once the order is placed. I know how to make an attachment in the mailoptions below but I cant figure out how to create the pdf and insert the product info.

// Triggers once the user place an order
exports.notifyUserOfOrderConfirmation = functions.firestore.document('masterOrders/{masterOrderId}').onCreate((snap, context) => {

    const data = snap.data();
    const orderedUserEmail = data.userEmail;
    const customerOrderId = data.customerOrderId;
    const userId = data.userId;
    const masterOrderId = context.params.masterOrderId;

    return orderProductsQuery(data, masterOrderId, orderedUserEmail, customerOrderId, userId)

});

// Query the firestore to get the ordered products
function orderProductsQuery(data, masterOrderId, orderedUserEmail, customerOrderId, userId) {

    return db.collection('users').doc(userId).collection('orders').doc(customerOrderId).collection('orderCart').get().then(snap => {
        const orderedProducts = [];
        snap.forEach(doc => {
            const productData = doc.data();
            orderedProducts.push(productData);
        })

        // return notifyUserOfOrderConfirmation(data, masterOrderId, orderedUserEmail, customerOrderId, orderedProducts)
        return generatePDF(data, masterOrderId, orderedUserEmail, customerOrderId, orderedProducts)

    }).catch((err) => {
        console.log('Error getting documents', err);
        return Promise.reject(err);
    })
}

This is where I need help with; below code is what I have written so far:

const pdfkit = require("pdfkit");
const Storage  = require('@google-cloud/storage');

// Creates a client
const storage = new Storage ({projectId: MYPROJECTID});

// Lists all buckets in the current project
const buckets = storage.getBuckets();

function generatePDF(data, masterOrderId, orderedUserEmail, customerOrderId, orderedProducts) {
    const doc = new pdfkit();
    const filename = `/${customerOrderId}/test-` + Date.now() + '.pdf'; 
    const bucket = storage.bucket(MYBUCKETNAME)    
    const file = bucket.file(filename);
    const bucketFileStream = file.createWriteStream();

    doc.pipe(bucketFileStream);

    doc.end();

    bucketFileStream.on('finish', function () {
        return notifyUserOfOrderConfirmation(filename, data, masterOrderId, orderedUserEmail, customerOrderId, orderedProducts)
    });

    bucketFileStream.on("error", function (err) {
        console.error(err);
    });
}

And here is when I send the email; I know this code below works just fine without the pdf codes so there is no issue with sending emails without pdf:

async function notifyUserOfOrderConfirmation(filename, data, masterOrderId, orderedUserEmail, customerOrderId, orderedProducts) {

    const bucket = storage.bucket(MYBUCKETNAME);
    const file = bucket.file(filename);    

    const mailOptions = {

        from: `${APP_NAME} <MYEMAIL>`,
        to: orderedUserEmail
    };

    mailOptions.subject = `Order Confirmation`;
    mailOptions.text = `We received your order. attached is your invoice`;

    mailOptions.attachments = [{
        filename: "test.pdf",
        content: file.createReadStream()
    }];

    await transporter.sendMail(mailOptions);
    console.log('New welcome email sent to:', orderedUserEmail);
    return null;
}

When I deploy this; I get no error in my deployment. But when I place an order in the app; I get the following error in the functions of firebase:

Error: socket hang up
    at TLSSocket.onHangUp (_tls_wrap.js:1148:19)
    at Object.onceWrapper (events.js:313:30)
    at emitNone (events.js:111:20)
    at TLSSocket.emit (events.js:208:7)
    at endReadableNT (_stream_readable.js:1064:12)
    at _combinedTickCallback (internal/process/next_tick.js:139:11)
    at process._tickDomainCallback (internal/process/next_tick.js:219:9)

Unhandled rejection

Any idea what is the problem here and I how I can generate the pdf correctly in this scenario?

user12669401 user12669401 · Accepted Answer · 2020-01-10T17:42:12

Figured it out. The above code is actually correct and I just simply had a wrong filename in here const file = bucket.file(filename); so there is no problem with this code and it works like a charm for whoever wants to use it to create pdf and email to the user.

Generate & email pdf in Cloud Functions using Node.js and Firebase cloudstore

1 Answers