Fixes

lib/chromium/pdf.rb

@@ -8,30 +8,39 @@ module Chromium
   module Pdf
     extend ActiveSupport::Concern
 
+    DEFAULT_CHROME_ARGUMENTS = [
+      '--headless',
+      '--disable-gpu',
+      '--no-pdf-header-footer',
+      '--run-all-compositor-stages-before-draw',
+      '--no-sandbox',
+      '--disable-dev-shm-usage',
+      '--disable-background-networking'
+    ].freeze
+
     ##
     # @param unescaped_filename [String] The filename to save the PDF as.
     # @param print_url [String] The URL of the page you want to be processed.
     # @param arguments [Array<String>] An array of arguments to pass to the Chrome binary.
     # @yield [file, filename] Yields the file object and the filename to the block.
     #
-    def generate_pdf!(unescaped_filename, print_url, arguments: ['--headless --disable-gpu'])
+    def generate_pdf!(unescaped_filename, print_url, arguments: DEFAULT_CHROME_ARGUMENTS, &block)
       chrome_path = ENV.fetch('GOOGLE_CHROME_BIN', nil)
       filename = unescaped_filename.gsub('&', 'and')
 
       Dir.mktmpdir do |path|
         filepath = "#{path}/#{filename}"
-
-        chrome_print chrome_path, print_url, filename, filepath, arguments
+        chrome_print chrome_path, print_url, filename, filepath, arguments, &block
       end
     end
 
     protected
 
-    def chrome_print(chrome_path, print_url, filename, filepath, arguments)
-      system("LD_PRELOAD='' #{chrome_path} --print-to-pdf='#{filepath}' #{arguments.join(' ')} #{print_url}")
+    def chrome_print(chrome_path, print_url, filename, filepath, arguments, &block)
+      Kernel.system("LD_PRELOAD='' #{chrome_path} --print-to-pdf='#{filepath}' #{arguments.join(' ')} #{print_url}")
 
       File.open(filepath) do |file|
-        yield file, filename
+        block&.call(file, filename)
       end
     end
   end

lib/generators/chromium/pdf/install/templates/app/jobs/generate_pdf_job.rb

@@ -12,7 +12,7 @@ class GeneratePdfJob < ApplicationJob
   good_job_control_concurrency_with(
     enqueue_limit: 1,
     perform_limit: 1,
-    key: arguments.first.id
+    key: -> { "generate_pdf_#{arguments.first.id}" }
   )
 
   around_perform do |_job, block|

test/chromium/test_pdf.rb

@@ -17,11 +17,24 @@ def test_generate_pdf_calls_chrome_print
 
   def test_chrome_print_calls_file_open
     job = TestGeneratePdfJob.new
-    File.stub :open, :ran do
-      result = job.send(:chrome_print, 'chrome', 'url', 'name', 'path', ['argument']) do |_file, filename|
-        assert_equal 'name', filename
+    Kernel.stub :system, true do
+      File.stub :open, :ran do
+        result = job.send(:chrome_print, 'chrome', 'url', 'name', 'path', ['argument']) do |_file, filename|
+          assert_equal 'name', filename
+        end
+        assert_equal :ran, result
+      end
+    end
+  end
+
+  def test_generate_pdf_yields_to_block
+    job = TestGeneratePdfJob.new
+    Kernel.stub :system, true do
+      File.stub :open, :ran do
+        job.generate_pdf!('filename', 'url') do |_file, filename|
+          assert_equal 'filename', filename
+        end
       end
-      assert_equal :ran, result
     end
   end
 end