bakso-doc

bakso-doc is a Node.js micro-service that creates PDF documents.

It uses Puppeteer and headless Chrome to request an HTML document and create a PDF.

Features:

• Simpler that propietary PDF-building syntaxes. Just use HTML & CSS.
• Simple stateless architecture
• Easy to setup

Menu

• Architecture
• CSS Styles for PDFs
• Get Started
• Delpoyment
• Error Monitoring
• Examples

Architecture

1. Originating app server requests a PDF document.
   1. The request contains the URL of an HTML page.
2. bakso-doc uses Puppeteer to request the HTML page.
3. Page.pdf method is called to generate a PDF document from the HTML page.
4. The entire PDF document is sent back in the response to the originating server.

Synchronous Requests

bakso-doc runs synchronously. When a document is requested, the request does not finish until the entire document is sent back. It is meant to be used in a queue system where the length of time to complete a request is not important.

bakso-doc is agnostic to other parts of the document processing system.

Page Request

Because Puppeteer/Chrome makes the requests diectly by setting the page URL, only GET requests can be made to the document page. You must pass any parameters in the URL query string.

Auth

In the interest of keeping server auth simple and easy to setup, bakso-doc authorizes requests with JWT tokens. The default is to generate a long-lived token for use on the requesting server.

Optionally, the secret can be shared across services and used to both sign and verify the tokens.

Print Stylesheet: Use HTML & CSS to Create Documents

CSS provides a powerful set of media queries and styles to be able to style a document.

@page {
  size: A4 landscape;
}

https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_media_queries/Printing

https://www.smashingmagazine.com/2011/11/how-to-set-up-a-print-style-sheet/

Get Started

Clone the repo:

$ git clone https://github.com/awongh/bakso-doc.git && cd bakso-doc

Install deps:

npm i

Generate the secret and set it in the .env file:

$ touch .env &&
echo "BAKSO_SECRET_KEY=\"$( node -e "console.log(require('crypto').randomBytes(256).toString('base64'));" )\"" >> .env

Generate a requesting token:

$ npm run generate_token <SECRET GOES HERE>

Generate a simple PDF Document

Set the requesting token in the Authorization request header.

Use cURL to make the request and download the file- create a test file called test.pdf in the current directory.

$ TEMP_TOKEN=$(npm run generate_token "<YOUR SECRET HERE>" | tail -n 1) &&
curl -X POST -H "Authorization: ${TEMP_TOKEN}" -H "Content-Type: application/json" --output test.pdf -d '{"pdfParams":{"renderUrl":"https://example.com"}}' http://localhost:5003/download/pdf

Params

See the schemas.js file to see the full accepted request params.

PDF Options

See the PDF options as defined by Pupeteer.

Example:

{
  "name":"myfile",
  "renderUrl":"https://localhost:3000/mydoc",
  "pdfOptions":{
    "width":"8.5in",
    "height":"11in",
    "printBackground":true
  }
}

Deployment

render.com

For deployment on render.com see the render.com branch.

Error Monitoring

Error monitoring with Sentry is already setup.

Add your Sentry DSN to the .env file:

BAKSO_SENTRY_DSN='<YOUR SENTRY DSN>'

Examples

Checkout the examples directory.

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