Merge pull request #60 from sanger/creating_printers_in_cupsd

Adding printer to cups

Dockerfile

@@ -3,6 +3,7 @@ ENV BUNDLER_VERSION=2.1.4
 
 RUN apt-get update -qq && apt-get install -y
 RUN apt-get -y install cups-client cups-bsd
+RUN apt-get -y install expect
 
 WORKDIR /code
 
@@ -14,6 +15,9 @@ ADD . /code/
 RUN gem install bundler
 RUN bundle install
 
+COPY create-cups-printer.sh /
+RUN ["chmod", "+x", "/create-cups-printer.sh"]
+
 COPY docker-entrypoint.sh /
 RUN ["chmod", "+x", "/docker-entrypoint.sh"]
 ENTRYPOINT ["/docker-entrypoint.sh"]

app/models/printer.rb

@@ -19,4 +19,25 @@ class Printer < ApplicationRecord
       filters
     end
   end
+
+  after_save :update_printer_in_cups
+
+  def update_printer_in_cups
+    return unless Rails.configuration.auto_create_printer_in_cupsd
+
+    existing_printers = Printer.existing_cups_printers
+    check_if_printer_exists(existing_printers)
+  end
+
+  def check_if_printer_exists(existing_printers)
+    return if existing_printers.include? name
+
+    `/create-cups-printer.sh #{name}`
+  end
+
+  def self.existing_cups_printers
+    existing_printers = `lpstat -a`.split("\n")
+    existing_printers.map! { |printer| printer.split(' ').first }
+    existing_printers
+  end
 end

config/environments/development.rb

@@ -52,6 +52,9 @@
   # Suppress logger output for asset requests.
   config.assets.quiet = true
 
+  # Default setting for adding printers to cupsd server on printer create
+  config.auto_create_printer_in_cupsd = false
+
   # Raises error for missing translations
   # config.action_view.raise_on_missing_translations = true
 

config/environments/production.rb

@@ -79,6 +79,9 @@
   # Use default logging formatter so that PID and timestamp are not suppressed.
   config.log_formatter = ::Logger::Formatter.new
 
+  # Default setting for adding printers to cupsd server on printer create
+  config.auto_create_printer_in_cupsd = true
+
   # Use a different logger for distributed setups.
   # require 'syslog/logger'
   # config.logger = ActiveSupport::TaggedLogging.new(Syslog::Logger.new 'app-name')

config/environments/test.rb

@@ -38,6 +38,9 @@
   # ActionMailer::Base.deliveries array.
   config.action_mailer.delivery_method = :test
 
+  # Default setting for adding printers to cupsd server on printer create
+  config.auto_create_printer_in_cupsd = false
+
   # Print deprecation notices to the stderr.
   config.active_support.deprecation = :stderr
 

create-cups-printer.sh

@@ -0,0 +1,6 @@
+#!/usr/bin/expect
+set printername [lindex $argv 0];
+spawn lpadmin -U "$env(CUPSD_USERNAME)" -p $printername -v socket://$printername.internal.sanger.ac.uk -E
+expect "Password for $env(CUPSD_USERNAME) on cupsd?"
+send -- "$env(CUPSD_PASSWORD)\n"
+expect eof

docker-entrypoint.sh

@@ -1,4 +1,10 @@
 #!/bin/bash
 mkdir /etc/cups/
 echo "ServerName $CUPSD_SERVER_NAME" > /etc/cups/client.conf
+if [ $CUPSD_UPDATE == "true" ]
+then
+    echo "-> Running printers rake task"
+    bundle exec rails printers:create
+    echo "-> Printers rake task complete"
+fi
 exec "$@"

lib/tasks/create_printers.rake

@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+# Can only run in production, unless config for auto_create_printer_in_cupsd is changed
+namespace :printers do
+  desc 'generate list of printers'
+  task create: :environment do |_t|
+    existing_printers = Printer.existing_cups_printers
+    Printer.all.each do |printer|
+      printer.check_if_printer_exists(existing_printers)
+    end
+  end
+end