Uses Chrome in Headless mode to print pages to PDF. Each page is loaded in it’s own browser context, similar to an Incognito window.

Pages may be printed that require authentication allowing you to print pages that are behind login wall.

When using HPDF you need to have a headless chrome running. By default HPDF will look for chrome at http://localhost:9222. This can be configured in your configuration files by using:

config :hpdf, HPDF,
  address: "http://my_custom_domain:9222"

You can get a headless chrome browser by using a docker container.

A public container can be found at: https://hub.docker.com/r/justinribeiro/chrome-headless/

docker run -d -p 9222:9222 --cap-add=SYS_ADMIN justinribeiro/chrome-headless

Example

case HPDF.print_page!(my_url, timeout: 30_000) do
  {:ok, pdf_data} -> do_stuff_with_the_pdf_binary_data(pdf_data)
  {:error, error_type, reason} -> #Handle error
  {:error, reason} -> # Handle error

Common error types provided by HPDF

• :page_error - An error was returned by the browser
• :page_redirected - The URL was redirected
• :page_load_failure - The page loaded with a non 200 status code
• :crashed - The browser crashed

Using header authentication

When printing a page using header authentication, usually it’s not only the original page, but all AJAX requests made within it that need to have the authentication header included.

Assuming you have a token

header_value = get_my_auth_header()
headers = %{"authorization" => header_value}

case HPDF.print_page!(my_url, timeout: 30_000, page_headers: headers) do
  {:ok, pdf_data} -> do_stuff_with_the_pdf_binary_data(pdf_data)
  {:error, error_type, reason} -> #Handle error
  {:error, reason} -> # Handle error
end

Using cookie authentication

An initiating cookie can be used to access pages.

cookie = %{
  name: "_cookie_name",
  value: cookie_value,
  domain: "your.domain",
  path: "/",
  secure: true,
  httpOnly: true,
}

{:ok, data} = HPDF.print_pdf!(url, timeout: 30_000, cookie: cookie)