Class: PrintNodeServer

Inherits:
ProxyServer show all
Defined in:
lib/print_node_server.rb

Constant Summary collapse

CHROME_PATH = 
"/Applications/Google Chrome.app/Contents/MacOS/Google Chrome"
POLL_EVERY =

seconds

10

Instance Method Summary collapse

Methods inherited from ProxyServer

#initialize, #set_mime_types

Constructor Details

This class inherits a constructor from ProxyServer

Instance Method Details

#check_for_requirements ⇒ Object 



18
19
20
21
 
# File 'lib/print_node_server.rb', line 18

def check_for_requirements
  raise "Could not find Google Chrome.  Please make sure Google Chrome is installed." if !File.exists?(CHROME_PATH)
  raise "Could not find chromehtml2pdf.  Run:\nnpm install -g chromehtml2pdf" if !File.which("chromehtml2pdf")
end

#default_printer ⇒ Object 



83
84
85
 
# File 'lib/print_node_server.rb', line 83

def default_printer
  ""
end

#loop_action ⇒ Object 



61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
 
# File 'lib/print_node_server.rb', line 61

def loop_action
  res = send_post
  if match = res.body.match(/<next-job>([^<]*)<\/next-job>/)
    url = match[1]
    path = "/tmp/VaePrintNode-#{rand.to_s.gsub(".", "")}.pdf"
    puts "Printing #{url} to #{path}"
    `chromehtml2pdf --marginLeft 0.5 --marginRight 0.5 --out "#{path}" #{Shellwords.shellescape(url)}`
    if File.exists?(path)
      `lp #{path}`
      Thread.new { sleep 15; FileUtils.rm(path) }
    else
      puts "Error: could not generate PDF!"
    end
  end
rescue StandardError => e
  puts e.message
end

#main_loop ⇒ Object 



53
54
55
56
57
58
59
 
# File 'lib/print_node_server.rb', line 53

def main_loop
  loop do
    break if @stop or (@last_successful_post_at + 3600) < Time.now
    loop_action if (@last_post_at + POLL_EVERY) < Time.now
    sleep 1
  end
end

#node_name ⇒ Object 



79
80
81
 
# File 'lib/print_node_server.rb', line 79

def node_name
  Socket.gethostname
end

#print_queue_status ⇒ Object 



91
92
93
 
# File 'lib/print_node_server.rb', line 91

def print_queue_status
  `lpq`
end

#printers_list ⇒ Object 



87
88
89
 
# File 'lib/print_node_server.rb', line 87

def printers_list
  `lpstat -p`
end

#register_node ⇒ Object 



23
24
25
26
27
28
29
30
 
# File 'lib/print_node_server.rb', line 23

def register_node
  res = send_post
  if match = res.body.match(/<secret-key>([a-f0-9]*)<\/secret-key>/)
    @node_id = "/#{match[1]}"
  else
    raise "Could not connect to Vae to register print node."
  end
end

#run ⇒ Object 



5
6
7
8
9
10
11
12
13
14
15
16
 
# File 'lib/print_node_server.rb', line 5

def run
  check_for_requirements
  register_node

  puts "Vae Print Node active, waiting for print jobs ..."
  puts "  (hit Control+C to exit)"

  trap("INT") { @stop = true }
  main_loop

  puts "Quit signal received, cleaning up ..."
end

#send_post ⇒ Object 



32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
 
# File 'lib/print_node_server.rb', line 32

def send_post
  @last_post_at = Time.now
  options = {
    method: :post,
    headers: { "Content-type": "application/json" },
    url: "#{@site.vaeplatform_url}/api/local/v1/print_nodes#{@node_id}",
    payload: {
      print_node: {
        name: node_name,
        default_printer: default_printer,
        printers_list: printers_list,
        print_queue_status: print_queue_status
      }
    }.to_json
  }
  options[:verify_ssl] = false if ENV['VAEPLATFORM_LOCAL']
  res = RestClient::Request.execute(options)
  @last_successful_post_at = Time.now
  res
end