Slide show widget

Slide Show.md

Description

This is Dashing widget to include slide show on your dashboard or one of its pages.

##Usage

Make sure to install RMagick gem to support image resizing. The widget also needs my slightly improved standard image widget. Put the slide_show.rb file in your /jobs folder and slide_show_settings.json to /assets/config/.

Make sure directory /assets/config and /assets/images/slide_show are accessible by Dashing user.

To include the widget in a dashboard, add the following snippet to the dashboard layout file:

<li data-row="1" data-col="1" data-sizex="4" data-sizey="2">
  <div data-id="SlideShow" data-view="Image" data-width="100%"></div>
</li>

There are 2 scheduler jobs used: First one gets randomized list of image files with pattern from source directory, resizes them to needed size and puts them to /assets/images/slide_show/<widget name>. It is executed at 5:00 and 18:00. Second randomly loops every 30 seconds through the files in /assets/images/slide_show/<widget name> and sends event with random file URL

##Settings

Mount your images directory to any directory on your server to be accessible by Dashing user. Amend /assets/config/slide_show_settings.json to have parameters specified.

There is no need to restart service if job is already running and settings file is amended.

slide_show.rb

require 'net/http'
require 'rmagick'

class SlideShow
  SETTINGS_FILE = "assets/config/slide_show_settings.json"
  CURRENT_DIR = Dir.pwd
  DEBUG = 0

  def debug
    DEBUG
  end

  # function to validate json
  def valid_json? (json)
    JSON.parse(json)
    return true
  rescue JSON::ParserError
    return false
  end

  def get_settings
     str = IO.read(SETTINGS_FILE)
     return [] if not str or str.empty? or not valid_json?(str)
     JSON.parse(str)
  end

  def get_dir_file_list(directory, pattern, exceptionDirs = [])
    # Take directory files using pattern and delete exception subdirectories
    Dir[directory+'/'+pattern].delete_if { |x| exceptionDirs.any? { |d| x =~ /#{d}/ } }
  end

  def resize_images(files, widget, directory, maxImageSize, quality = 50, fileCount = 100)
    return if not files or files.length == 0
    files[0..fileCount].each do |f|
      newFile = f.sub directory, CURRENT_DIR+"/assets/images/slide_show/#{widget}"
      next if File.exists?(newFile)
      FileUtils.mkdir_p File.dirname(newFile)
      img = Magick::Image.read(f).first
      newImg = img.change_geometry(maxImageSize[0].to_s+'x'+maxImageSize[1].to_s) { |cols, rows, i|
        newImg = i.resize(cols, rows)
        newImg.write(newFile){ self.quality = quality }
      }
    end
  end

  def get_file_list(widget, settings)
    widgetFileDir = CURRENT_DIR+"/assets/images/slide_show/#{widget}"
    files = (get_dir_file_list(widgetFileDir, settings['pattern']).shuffle)[0..30]
    return files if files and files.length > 0
    # no files yet - get new list from source location and resize it
    # take just 15 files not to freeze everything
    resize_images(
      get_dir_file_list(settings['directory'], settings['pattern'], settings['subDirectoryExceptions']).shuffle,
      widget,
      settings['directory'],
      settings['maxImageSize'],
      settings['quality'],
      15)
    # return 10 files not to make everything last too long
    (get_dir_file_list(widgetFileDir, settings['pattern']).shuffle)[0..10]
  end
  
  
  def make_web_friendly(widget, directory, file)
    file.sub directory, "/assets/slide_show/#{widget}" if file
  end
end

@SS = SlideShow.new()
SCHEDULER.cron '* 5/18 * * *' do |job|
  settings = @SS.get_settings
  settings.each do |widget, project|
    puts DateTime.now.to_s+" Resizing images for #{widget}, #{project.to_s}"
    @SS.resize_images(
      @SS.get_dir_file_list(project['directory'], project['pattern'], project['subDirectoryExceptions']).shuffle,
      widget,
      project['directory'],
      project['maxImageSize'],
      project['quality'])
  end
end

@files = nil
SCHEDULER.every '30s', :first_in => 0 do |job|
  settings = @SS.get_settings
  settings.each do |widget, project|
    @files = { widget => @SS.get_file_list(widget, project) } if not @files or not @files[widget] or @files[widget].length == 0
    file = @files[widget][rand(@files[widget].length)]
    puts DateTime.now.to_s+" Working with #{widget}, #{project.to_s}, #{file}" if @SS.debug > 0
    img = Magick::Image::read(file).first
    send_event(widget, {
       image: @SS.make_web_friendly(widget, Dir.pwd+"/assets/images/slide_show/#{widget}", file),
       image_width: img.columns,
       image_height: img.rows
    })
  end
end

slide_show_settings.json

{"SlideShow":{"directory":"/mnt/images/Public TV","pattern":"**/*.{jpg,JPG,gif,GIF,png,PNG}","maxImageSize":[1920,1080],"quality":50,"subDirectoryExceptions":["very bad party","personal employee pictures","something very private"]}}

@slize,

Thanks for nice words and especially for your excellent QA work! Yesterday I started wondering myself, why those pictures are always the same ;). Code updated.

Hi , thanks for your nice gadget but it generates a script leak memory for each new pictures.

Hi Brunas,
I've been trying to get this to work but just can't get there,
can you give me a clue as to why I'd get this error when starting dashing

/Users/tkcharlie/ce_dashboard/jobs/slide_show.rb:90:in read' /Users/tkcharlie/ce_dashboard/jobs/slide_show.rb:90:inblock (2 levels) in <top (required)>'
/Users/tkcharlie/ce_dashboard/jobs/slide_show.rb:86:in each' /Users/tkcharlie/ce_dashboard/jobs/slide_show.rb:86:inblock in <top (required)>'

I've been trying to get this to work for days, but it's not happening. It keeps getting RMagick error messages. Is it possible to get this widget without the resizing part?

Hi Brunas, Thanks for the widget. It's working, however there is still a problem with image duplications. Another question, how to stop the shuffling? Thanks.

Hi,

thanks for that great widget!
Is there a way to stop the randomized slideshow? Would be nice to display the images in a fixed order.

thx