write script to delete unused images.

1 files changed, 34 insertions, 0 deletions

diff --git a/week-7/final7/solve.rb b/week-7/final7/solve.rb
new file mode 100644
index 0000000..fff2a2f
--- /dev/null
+++ b/week-7/final7/solve.rb
@@ -0,0 +1,34 @@
+require 'rubygems'
+require 'bundler'
+Bundler.require
+
+def main
+  client = Mongo::MongoClient.new
+  db = client['final7']
+  images_collection = db['images']
+  albums_collection = db['albums']
+
+  albums = albums_collection.aggregate([
+    { '$unwind': '$images' }, 
+    { '$project': { '_id': '$images' } },
+    { '$group': { '_id': '$_id', count: { '$sum': 1 } } },
+  ])
+  used_images = albums.reduce({}) do |memo, image|
+    memo[image['_id']] = true
+    memo
+  end
+  images = images_collection.find().to_a
+  deleted = 0
+  images.each do |image|
+    image_id = image['_id']
+    if used_images.key?(image_id) == false
+      puts "Deleting: #{image_id}"
+      #images_collection.remove("_id": image_id)
+      deleted += 1
+    end
+  end
+  puts "USED: #{used_images.size}"
+  puts "DELETED: #{deleted}"
+end
+
+main