Dhalang is a Ruby wrapper for Google's Puppeteer.
- Generate PDFs from pages
- Generate PDFs from html ( external images/stylesheets supported )
- Capture a screenshot of a webpage
Add this line to your application's Gemfile:
gem 'Dhalang'
And then execute:
$ bundle update
Install puppeteer in your application's root directory:
$ npm install puppeteer
NodeJS v10.18.1 or greater is required
Get a PDF of a website url
Dhalang::PDF.get_from_url("https://www.google.com")
It is important to pass the complete url, leaving out https://, http:// or www. will result in an error.
Get a PDF of a HTML string
Dhalang::PDF.get_from_html("<html><head></head><body><h1>examplestring</h1></body></html>")
Get a PNG screenshot of a website
Dhalang::Screenshot.get_from_url_as_png("https://www.google.com")
Get a JPEG screenshot of a website
Dhalang::Screenshot.get_from_url_as_jpeg("https://www.google.com")
All methods return a string containing the PDF or JPEG/PNG in binary.
To override the default PDF options that are set by Dhalang you can pass as last argument a hash with the custom options you want to set.
For example to set custom margins:
Dhalang::PDF.get_from_url("https://www.google.com", {margin: { top: 100, right: 100, bottom: 100, left: 100}})
For a list of all possible options that can be set, please check out: https://github.com/puppeteer/puppeteer/blob/main/docs/api.md#pagepdfoptions
You may want to change the way Dhalang interacts with Puppeteer in general. User options can be set by providing them in a hash as last argument to any calls you make to the library. Are you setting both custom PDF and user options? Then they should be passed as a single hash.
For example to set a custom navigation timeout:
Dhalang::Screenshot.get_from_url_as_jpeg("https://www.google.com", {navigation_timeout: 20000})
Below table lists all possible configuration parameters that can be set:
| Key | Description | Default |
|---|---|---|
| navigation_timeout | Amount of milliseconds until Puppeteer while timeout when navigating to the given page | 10000 |
| user_agent | User agent to send with the request | Default Puppeteer one |
| view_port | Custom viewport to use for the request | Default Puppeteer one |
| http_authentication_credentials | Custom HTTP authentication credentials to use for the request | None |
To return a PDF from a Rails controller you can do the following:
def example_controller_method
binary_pdf = Dhalang::PDF.get_from_url("https://www.google.com")
send_data(binary_pdf, filename: 'pdfofgoogle.pdf', type: 'application/pdf')
end
To return a PNG from a Rails controller you can do the following:
def example_controller_method
binary_png = Dhalang::Screenshot.get_from_url_as_png("https://www.google.com")
send_data(binary_png, filename: 'screenshotofgoogle.png', type: 'image/png')
end
To return a JPEG from a Rails controller you can do the following:
def example_controller_method
binary_jpeg = Dhalang::Screenshot.get_from_url_as_jpeg("https://www.google.com")
send_data(binary_jpeg, filename: 'screenshotofgoogle.jpeg', type: 'image/jpeg')
end