Getting imgkit + paperclip + s3 to work. Paperclip isn't recognizing "snapshot"

Question

EDIT: One problem was I need to do r = Resource.where(id: 3).first #<== I didn't have the .first before

I'm attempting to get snapshots of URLs by using imgkit + paperclip + s3. I am able to get the snapshots, and successfully upload them to paperclip. For example, the IRB session at the bottom of this post successfully uploads a snapshot of the specified URL to my S3 bucket.

However, I am trying to display the images, and I always get a missing.png image. I experimented in the IRB session given below and found something interesting. I don't think that I am saving resource.snapshot correctly, because I can't get that url again if I find the resource under a different variable name (look at the IRB session below).

All I want to know is how I can get the url of the image I uploaded to S3.

I ran "rails generate paperclip resource snapshot" and then "rake db:migrate" successfully.

Gemfile:

# IMGKit for site thumbnails
gem "imgkit", "~> 1.3.7"

# Amazon S3 storage
gem 'aws-sdk', '~> 1.3.4'

# Paperclip for file uploads
gem "paperclip", :git => "git://github.com/thoughtbot/paperclip.git"

In my resource.rb model:

attr_accessible :snapshot
  has_attached_file :snapshot,
                    :storage => :s3,
                    :s3_credentials => "#{Rails.root}/config/s3.yml"

Here's my IRB session:

128-110-88-73:KnowledgeThief dainewinters$ rails c
    Loading development environment (Rails 3.2.11)
    irb(main):001:0> r = Resource.first
      Resource Load (0.9ms)  SELECT "resources".* FROM "resources" LIMIT 1
    => nil
    irb(main):002:0> r = Resource.first
      Resource Load (1.1ms)  SELECT "resources".* FROM "resources" LIMIT 1
    => #<Resource id: 1, link: "http://cm.dce.harvard.edu/2012/01/13836/publication...", title: "Harvard CS61 - Computer Systems", description: "Harvard's version of CS4400. Topics include assembl...", user_id: nil, created_at: "2013-02-03 20:36:01", updated_at: "2013-02-03 20:36:01", youtubeID: nil, media_type: "video", snapshot_file_name: nil, snapshot_content_type: nil, snapshot_file_size: nil, snapshot_updated_at: nil>
    irb(main):003:0> url = r.link
    => "http://cm.dce.harvard.edu/2012/01/13836/publicationListing.shtml"
    irb(main):004:0> url = PostRank::URI.clean(r.link)
    => "http://cm.dce.harvard.edu/2012/01/13836/publicationListing.shtml"
    irb(main):005:0> side_size = 300
    => 300
    irb(main):006:0> crop_side_size = 300
    => 300
    irb(main):007:0> kit = IMGKit.new(url, :quality => 50,
    irb(main):008:1*                           :width   => side_size,
    irb(main):009:1*                           :height  => side_size,
    irb(main):010:1*                           "crop-w" => crop_side_size,
    irb(main):011:1*                           "crop-h" => crop_side_size,
    irb(main):012:1*                           "zoom"   => 0.35,
    irb(main):013:1*                           "disable-smart-width" => true,
    irb(main):014:1*                           "load-error-handling" => "ignore")
    => #<IMGKit:0x007fa11599adc8 @options={:quality=>50, :width=>300, :height=>300, "crop-w"=>300, "crop-h"=>300, "zoom"=>0.35, "disable-smart-width"=>true, "load-error-handling"=>"ignore"}, @stylesheets=[], @source=http://cm.dce.harvard.edu/2012/01/13836/publicationListing.shtml>
    irb(main):015:0> img = kit.to_img(:jpg)
    => "\xFF\xD8\xFF\xE0\x00\x10JFIF\x00\x01\x01\x01..."
    irb(main):016:0> r.id
    => 1
    irb(main):017:0> r.object_id
    => 70164904582860
    irb(main):018:0> file = Tempfile.new(["resource_snapshot_#{r.id}
    irb(main):019:2" ", 'jpg'], 'tmp', :encoding => 'ascii-8bit')
    => #<File:/Users/dainewinters/rails/KnowledgeThief/tmp/resource_snapshot_1
    20130203-28526-1fpqdwljpg>
    irb(main):020:0> file.write(img)
    => 9756
    irb(main):021:0> file.flush
    => #<File:/Users/dainewinters/rails/KnowledgeThief/tmp/resource_snapshot_1
    20130203-28526-1fpqdwljpg>
    irb(main):022:0> r.snapshot
    => /snapshots/original/missing.png
    irb(main):023:0> r.snapshot = file
    => #<File:/Users/dainewinters/rails/KnowledgeThief/tmp/resource_snapshot_1
    20130203-28526-1fpqdwljpg>
    irb(main):024:0> r.snapshot
    => http://s3.amazonaws.com/knowledgethief-dev/resources/snapshots/000/000/001/original/resource_snapshot_1%0A20130203-28526-1fpqdwljpg?1359924148
    irb(main):025:0> r.save!
       (0.2ms)  BEGIN
       (0.9ms)  UPDATE "resources" SET "snapshot_file_name" = 'resource_snapshot_1
    20130203-28526-1fpqdwljpg', "snapshot_content_type" = 'image/jpeg', "snapshot_file_size" = 9756, "snapshot_updated_at" = '2013-02-03 20:42:28.408205', "updated_at" = '2013-02-03 20:42:35.031108' WHERE "resources"."id" = 1
       (0.8ms)  COMMIT
    => true
    irb(main):026:0> r
    => #<Resource id: 1, link: "http://cm.dce.harvard.edu/2012/01/13836/publication...", title: "Harvard CS61 - Computer Systems", description: "Harvard's version of CS4400. Topics include assembl...", user_id: nil, created_at: "2013-02-03 20:36:01", updated_at: "2013-02-03 20:42:35", youtubeID: nil, media_type: "video", snapshot_file_name: "resource_snapshot_1\n20130203-28526-1fpqdwljpg", snapshot_content_type: "image/jpeg", snapshot_file_size: 9756, snapshot_updated_at: "2013-02-03 20:42:28">
    irb(main):027:0> r.snapshot
    => http://s3.amazonaws.com/knowledgethief-dev/resources/snapshots/000/000/001/original/resource_snapshot_1%0A20130203-28526-1fpqdwljpg?1359924148
    irb(main):028:0> file.unlink
    => nil
    irb(main):029:0> r.snapshot
    => http://s3.amazonaws.com/knowledgethief-dev/resources/snapshots/000/000/001/original/resource_snapshot_1%0A20130203-28526-1fpqdwljpg?1359924148
    irb(main):030:0> r.snapshot.url
    => "http://s3.amazonaws.com/knowledgethief-dev/resources/snapshots/000/000/001/original/resource_snapshot_1%0A20130203-28526-1fpqdwljpg?1359924148"
    irb(main):031:0> r2 = Resource.first
      Resource Load (2.3ms)  SELECT "resources".* FROM "resources" LIMIT 1
    => #<Resource id: 2, link: "http://www.codeschool.com/courses/try-git", title: "Try Git", description: "A great introduction to Git, a popular version cont...", user_id: nil, created_at: "2013-02-03 20:36:01", updated_at: "2013-02-03 20:36:01", youtubeID: nil, media_type: "interactive course", snapshot_file_name: nil, snapshot_content_type: nil, snapshot_file_size: nil, snapshot_updated_at: nil>
    irb(main):032:0> r2
    => #<Resource id: 2, link: "http://www.codeschool.com/courses/try-git", title: "Try Git", description: "A great introduction to Git, a popular version cont...", user_id: nil, created_at: "2013-02-03 20:36:01", updated_at: "2013-02-03 20:36:01", youtubeID: nil, media_type: "interactive course", snapshot_file_name: nil, snapshot_content_type: nil, snapshot_file_size: nil, snapshot_updated_at: nil>
    irb(main):033:0> r2.snapshot
    => /snapshots/original/missing.png
    irb(main):034:0> r
    => #<Resource id: 1, link: "http://cm.dce.harvard.edu/2012/01/13836/publication...", title: "Harvard CS61 - Computer Systems", description: "Harvard's version of CS4400. Topics include assembl...", user_id: nil, created_at: "2013-02-03 20:36:01", updated_at: "2013-02-03 20:42:35", youtubeID: nil, media_type: "video", snapshot_file_name: "resource_snapshot_1\n20130203-28526-1fpqdwljpg", snapshot_content_type: "image/jpeg", snapshot_file_size: 9756, snapshot_updated_at: "2013-02-03 20:42:28">
    irb(main):035:0> r2 = Resource.where(id: 1)
      Resource Load (0.6ms)  SELECT "resources".* FROM "resources" WHERE "resources"."id" = 1
    => [#<Resource id: 1, link: "http://cm.dce.harvard.edu/2012/01/13836/publication...", title: "Harvard CS61 - Computer Systems", description: "Harvard's version of CS4400. Topics include assembl...", user_id: nil, created_at: "2013-02-03 20:36:01", updated_at: "2013-02-03 20:42:35", youtubeID: nil, media_type: "video", snapshot_file_name: "resource_snapshot_1\n20130203-28526-1fpqdwljpg", snapshot_content_type: "image/jpeg", snapshot_file_size: 9756, snapshot_updated_at: "2013-02-03 20:42:28">]
    irb(main):036:0> r2
    => [#<Resource id: 1, link: "http://cm.dce.harvard.edu/2012/01/13836/publication...", title: "Harvard CS61 - Computer Systems", description: "Harvard's version of CS4400. Topics include assembl...", user_id: nil, created_at: "2013-02-03 20:36:01", updated_at: "2013-02-03 20:42:35", youtubeID: nil, media_type: "video", snapshot_file_name: "resource_snapshot_1\n20130203-28526-1fpqdwljpg", snapshot_content_type: "image/jpeg", snapshot_file_size: 9756, snapshot_updated_at: "2013-02-03 20:42:28">]
    irb(main):037:0> r2.snapshot
    NoMethodError: undefined method `snapshot' for #<ActiveRecord::Relation:0x007fa115d42b88>
        from /Users/dainewinters/.rbenv/versions/1.9.3-p327-perf/lib/ruby/gems/1.9.1/gems/activerecord-3.2.11/lib/active_record/relation/delegation.rb:45:in `method_missing'
        from (irb):37
        from /Users/dainewinters/.rbenv/versions/1.9.3-p327-perf/lib/ruby/gems/1.9.1/gems/railties-3.2.11/lib/rails/commands/console.rb:47:in `start'
        from /Users/dainewinters/.rbenv/versions/1.9.3-p327-perf/lib/ruby/gems/1.9.1/gems/railties-3.2.11/lib/rails/commands/console.rb:8:in `start'
        from /Users/dainewinters/.rbenv/versions/1.9.3-p327-perf/lib/ruby/gems/1.9.1/gems/railties-3.2.11/lib/rails/commands.rb:41:in `<top (required)>'
        from script/rails:12:in `require'
        from script/rails:12:in `<main>'
    irb(main):038:0> r2.snapshot_file_name
    NoMethodError: undefined method `snapshot_file_name' for #<ActiveRecord::Relation:0x007fa115d42b88>
        from /Users/dainewinters/.rbenv/versions/1.9.3-p327-perf/lib/ruby/gems/1.9.1/gems/activerecord-3.2.11/lib/active_record/relation/delegation.rb:45:in `method_missing'
        from (irb):38
        from /Users/dainewinters/.rbenv/versions/1.9.3-p327-perf/lib/ruby/gems/1.9.1/gems/railties-3.2.11/lib/rails/commands/console.rb:47:in `start'
        from /Users/dainewinters/.rbenv/versions/1.9.3-p327-perf/lib/ruby/gems/1.9.1/gems/railties-3.2.11/lib/rails/commands/console.rb:8:in `start'
        from /Users/dainewinters/.rbenv/versions/1.9.3-p327-perf/lib/ruby/gems/1.9.1/gems/railties-3.2.11/lib/rails/commands.rb:41:in `<top (required)>'
        from script/rails:12:in `require'
        from script/rails:12:in `<main>'
    irb(main):039:0> r2
    => [#<Resource id: 1, link: "http://cm.dce.harvard.edu/2012/01/13836/publication...", title: "Harvard CS61 - Computer Systems", description: "Harvard's version of CS4400. Topics include assembl...", user_id: nil, created_at: "2013-02-03 20:36:01", updated_at: "2013-02-03 20:42:35", youtubeID: nil, media_type: "video", snapshot_file_name: "resource_snapshot_1\n20130203-28526-1fpqdwljpg", snapshot_content_type: "image/jpeg", snapshot_file_size: 9756, snapshot_updated_at: "2013-02-03 20:42:28">]
    irb(main):040:0> 

Answer 1

Turns out, I was doing everything right except:

r = Resource.where(id: 3)

Needs to be

r = Resource.where(id: 3).first

As the first one returns an array.