Ruby script to change desktop wallpaper in Plasma > 5.7 from GoPro photo of the day

set_kde_wallpaper.rb

require 'net/http'
require 'open-uri'
require 'open3'
require 'json'
require 'optparse'
require 'tempfile'

options = {}
OptionParser.new do |opts|
  opts.banner = "Usage: #{__FILE__} [options]"

  opts.on('-nNUMBER', '--number=NUMBER', 'Image number from 1 to 9') do |n|
    options[:number] = n
  end

  opts.on("-h", "--help", "Prints this help") do
    puts opts
    exit
  end
end.parse!

number = options[:number] ? options[:number].match(/\A[1-9]{1}\z/) ? $&.to_i : 1 : 1
number -= 1

url = 'https://api.gopro.com/v2/channels/feed/playlists/photo-of-the-day.json?platform=web&page=1&per_page=9'

uri = URI(url)
response = Net::HTTP.get(uri)
data = JSON.parse(response)

image_url = data['media'][number]['thumbnails']['full']['image']
image_uri = URI(image_url)

image_file = Tempfile.new('gopro_wallpaper')

set_wallpaper_script = %Q[
  var allDesktops = desktops();
  print (allDesktops);
  for (i=0; i<allDesktops.length; i++) {
    d = allDesktops[i];
    d.wallpaperPlugin = "org.kde.image";
    d.currentConfigGroup = Array("Wallpaper", "org.kde.image", "General");
    d.writeConfig("Image", "file://#{image_file.path}")
  }
]

begin
  # Download image to tempfile
  File.open(image_file, "wb") do |f|
    open(image_url, "rb") do |read_file|
      f.write(read_file.read)
    end
  end

  stdin, stdout, stderr, wait_thr = Open3.popen3(
    "qdbus org.kde.plasmashell /PlasmaShell org.kde.PlasmaShell.evaluateScript '#{set_wallpaper_script}'"
  )

  if stdout.read =~ /Widgets are locked/
    puts "Cannot change the wallpaper while widgets are locked! (unlock the widgets)"
    exit
  end

  sleep 1
ensure
  image_file.close
end

Unfortunately, I didn't find a way to unlock widgets programmatically.