Puppeteer is a library which basically provides high level Api's that lets us run the browser from Node.js. So we can use it to generate Pdf's and many other things.
yarn add dev serverless pupeteer
yarn add chrome-aws-lambda pug puppeteer-core serverless-apigw-binary serverless-offline
We use the serverless library to handle our AWS step and also to run our lambda functions locally. Serverless.yml is a configuration file where we can define our AWS resources and do other fun things. Refer the docs.
Before you begin, setup your AWS Credentials.
Then create a serverless.yml file and add this
service: pdf-puppeteer
provider:
name: aws
runtime: nodejs8.10
stage: dev
profile: default
plugins:
- serverless-offline
functions:
pdf:
handler: pdf.pdf
serverless-offline is a serverless plugin that lets us run the pdf lambda function locally. More on that later.
These two libraries do all the magic for us. Since the deployment package for AWS Lambda will go over the size limit, we can't use the full version of puppeteer
. Puppeteer
is around 300 MB because it downloads Chromium during yarn add
before exposing the API. But luckily, chrome-aws-lambda
ships the chromium binary for serverless environments and puppeteer-core is a version of Puppeteer that is only 2 MB and which can connect to our own Chromium instance of choice. So together with chrome-aws-lambda it provides a “full” puppeteer and is small enough to be deployed.
If you try to run our lambda function locally using serverless invoke local -f pdf
, it won't work because puppeteer-core
doesn’t download chromium and chrome-aws-lambda
is only for AWS lambda, ie not for your local environment. To make it run locally, we need to install the full puppeteer
as devDependencies, and in the code we need to check if the request comes from serverless-offline, if yes then set the executablePath to your local Chromium.
./node_modules/puppeteer/.local-chromium/mac-674921/chrome-mac/Chromium.app/Contents/MacOS/Chromium
is the local executablePath for chromium we installed with puppeteer on devDependencies.
event.isOffline
in pdf.js
checks if we are running serverless locally and sets the executable path accordingly.
This is the full code inside our lambda function.
"use strict";
const chromium = require("chrome-aws-lambda");
var AWS = require("aws-sdk");
const pug = require("pug");
const fs = require("fs");
const path = require("path");
AWS.config.update({ region: "us-east-1" });
const s3 = new AWS.S3();
module.exports.pdf = async (event, context, callBack) => {
const dummyData = {
name: "Ayappa Reddy"
};
const executablePath = event.isOffline
? "./node_modules/puppeteer/.local-chromium/mac-674921/chrome-mac/Chromium.app/Contents/MacOS/Chromium"
: await chromium.executablePath;
const template = pug.compileFile("./template.pug");
const html = template({ ...dummyData });
let browser = null;
try {
browser = await chromium.puppeteer.launch({
args: chromium.args,
defaultViewport: chromium.defaultViewport,
executablePath,
headless: chromium.headless
});
const page = await browser.newPage();
page.setContent(html);
const pdf = await page.pdf({
format: "A4",
printBackground: true,
margin: { top: "1cm", right: "1cm", bottom: "1cm", left: "1cm" }
});
// TODO: Response with PDF (or error if something went wrong )
const response = {
headers: {
"Content-type": "application/pdf",
"content-disposition": "attachment; filename=test.pdf"
},
statusCode: 200,
body: pdf.toString("base64"),
isBase64Encoded: true
};
const output_filename = `invoice.pdf`;
const s3Params = {
Bucket: "pdf-puppeteer",
Key: `public/pdfs/${output_filename}`,
Body: pdf,
ContentType: "application/pdf",
ServerSideEncryption: "AES256"
};
s3.putObject(s3Params, err => {
if (err) {
console.log("err", err);
return callBack(null, { error });
}
});
context.succeed(response);
// fs.writeFileSync("invoice.pdf", pdf); // Locally
} catch (error) {
return context.fail(error);
} finally {
if (browser !== null) {
await browser.close();
}
}
};
We have already created a S3 bucket called "pdf-puppeteer" in our AWS account. All the generated pdfs will be saved under /pdf-puppeteer/public/pdfs/invoice.pdf
if you run the lambda either locally or in development. Please create a bucket in S3 if you wish so and modify pdf.js
with the correct bucket name in s3Params
.
If you would like to see your changes locally without saving to S3 all the time and instead to invoice.pdf
at the root of the project directory. Modify pdf.js
like so,
"use strict";
const chromium = require("chrome-aws-lambda");
var AWS = require("aws-sdk");
const pug = require("pug");
const fs = require("fs");
const path = require("path");
module.exports.pdf = async (event, context, callBack) => {
const dummyData = {
name: "Ayappa Reddy"
};
const executablePath = event.isOffline
? "./node_modules/puppeteer/.local-chromium/mac-674921/chrome-mac/Chromium.app/Contents/MacOS/Chromium"
: await chromium.executablePath;
const template = pug.compileFile("./template.pug");
const html = template({ ...dummyData });
let browser = null;
try {
browser = await chromium.puppeteer.launch({
args: chromium.args,
defaultViewport: chromium.defaultViewport,
executablePath,
headless: chromium.headless
});
const page = await browser.newPage();
page.setContent(html);
const pdf = await page.pdf({
format: "A4",
printBackground: true,
margin: { top: "1cm", right: "1cm", bottom: "1cm", left: "1cm" }
});
// TODO: Response with PDF (or error if something went wrong )
const response = {
headers: {
"Content-type": "application/pdf",
"content-disposition": "attachment; filename=test.pdf"
},
statusCode: 200,
body: pdf.toString("base64"),
isBase64Encoded: true
};
context.succeed(response);
fs.writeFileSync("invoice.pdf", pdf); // Locally
} catch (error) {
return context.fail(error);
} finally {
if (browser !== null) {
await browser.close();
}
}
} ;
All we did here was remove the code that saves the pdf to S3 and instead uncomment the part that says fs.writeFileSync("invoice.pdf", pdf)
We use `pug` as the templating engine for our HTML.
Create a file `template.pug` at the root of the project directory and add your HTML.
In `pdf.js`, the two lines below will compile our template file with the data, possibly from the db.
const template = pug.compileFile("./template.pug");
const html = template({ ...dummyData });
Here is a basic template.pug
file.
doctype html
html(lang="en")
head
meta(charset="utf-8")
title Example 2
style
include style.css
body
header.clearfix
#logo
img(src="./logo.png")
#company
h2.name Company Name
div 455 Foggy Heights, AZ 85004, US
div (602) 519-0450
div
a(href="mailto:[email protected]") [email protected]
main
#details.clearfix
#client
.to INVOICE TO:
h2.name John Doe
.address 796 Silver Harbour, TX 79273, US
.email
a(href="mailto:[email protected]") [email protected]
#invoice
h1 INVOICE 3-2-1
.date Date of Invoice: 01/06/2014
.date Due Date: 30/06/2014
table(border="0" cellspacing="0" cellpadding="0")
thead
tr
th.no #
th.desc DESCRIPTION
th.unit UNIT PRICE
th.qty QUANTITY
th.total TOTAL
tbody
tr
td.no 01
td.desc
h3 Website Design
| Creating a recognizable design solution based on the company's existing visual identity
td.unit $40.00
td.qty 30
td.total $1,200.00
tr
td.no 02
td.desc
h3 Website Development
| Developing a Content Management System-based Website
td.unit $40.00
td.qty 80
td.total $3,200.00
tr
td.no 03
td.desc
h3 Search Engines Optimization
| Optimize the site for search engines (SEO)
td.unit $40.00
td.qty 20
td.total $800.00
tfoot
tr
td(colspan="2")
td(colspan="2") SUBTOTAL
td $5,200.00
tr
td(colspan="2")
td(colspan="2") TAX 25%
td $1,300.00
tr
td(colspan="2")
td(colspan="2") GRAND TOTAL
td $6,500.00
#thanks Thank you!
#notices
div NOTICE:
.notice A finance charge of 1.5% will be made on unpaid balances after 30 days.
footer
| Invoice was created on a computer and is valid without the signature and seal.
The line include style.css
includes our stylesheet style.css
from the project root.
@font-face {
font-family: SourceSansPro;
src: url(SourceSansPro-Regular.ttf);
}
.clearfix:after {
content: "";
display: table;
clear: both;
}
a {
color: #0087c3;
text-decoration: none;
}
body {
position: relative;
width: 21cm;
height: 29.7cm;
margin: 0 auto;
color: #555555;
background: #ffffff;
font-family: Arial, sans-serif;
font-size: 14px;
font-family: SourceSansPro;
}
header {
padding: 10px 0;
margin-bottom: 20px;
border-bottom: 1px solid #aaaaaa;
}
#logo {
float: left;
margin-top: 8px;
}
#logo img {
height: 70px;
}
#company {
float: right;
text-align: right;
}
#details {
margin-bottom: 50px;
}
#client {
padding-left: 6px;
border-left: 6px solid #0087c3;
float: left;
}
#client .to {
color: #777777;
}
h2.name {
font-size: 1.4em;
font-weight: normal;
margin: 0;
}
#invoice {
float: right;
text-align: right;
}
#invoice h1 {
color: #0087c3;
font-size: 2.4em;
line-height: 1em;
font-weight: normal;
margin: 0 0 10px 0;
}
#invoice .date {
font-size: 1.1em;
color: #777777;
}
table {
width: 100%;
border-collapse: collapse;
border-spacing: 0;
margin-bottom: 20px;
}
table th,
table td {
padding: 20px;
background: #eeeeee;
text-align: center;
border-bottom: 1px solid #ffffff;
}
table th {
white-space: nowrap;
font-weight: normal;
}
table td {
text-align: right;
}
table td h3 {
color: #57b223;
font-size: 1.2em;
font-weight: normal;
margin: 0 0 0.2em 0;
}
table .no {
color: #ffffff;
font-size: 1.6em;
background: #57b223;
}
table .desc {
text-align: left;
}
table .unit {
background: #dddddd;
}
table .qty {
}
table .total {
background: #57b223;
color: #ffffff;
}
table td.unit,
table td.qty,
table td.total {
font-size: 1.2em;
}
table tbody tr:last-child td {
border: none;
}
table tfoot td {
padding: 10px 20px;
background: #ffffff;
border-bottom: none;
font-size: 1.2em;
white-space: nowrap;
border-top: 1px solid #aaaaaa;
}
table tfoot tr:first-child td {
border-top: none;
}
table tfoot tr:last-child td {
color: #57b223;
font-size: 1.4em;
border-top: 1px solid #57b223;
}
table tfoot tr td:first-child {
border: none;
}
#thanks {
font-size: 2em;
margin-bottom: 50px;
}
#notices {
padding-left: 6px;
border-left: 6px solid #0087c3;
}
#notices .notice {
font-size: 1.2em;
}
footer {
color: #777777;
width: 100%;
height: 30px;
position: absolute;
bottom: 0;
border-top: 1px solid #aaaaaa;
padding: 8px 0;
text-align: center;
}
Refer the pug
docs for more info on creating your HTML.
Finally, use sls deploy
to deploy the lambda function to AWS.