metadata: add ability to search exif metadata.

Usage:

* https://danbooru.donmai.us/media_metadata?search[has_metadata]=true
* https://danbooru.donmai.us/media_metadata?search[has_metadata]=false
* https://danbooru.donmai.us/media_metadata?search[metadata_has_key]=GIF:GIFVersion
* https://danbooru.donmai.us/media_metadata?search[metadata][GIF:GIFVersion]=89a
* https://danbooru.donmai.us/media_metadata?search[metadata][GIF:GIFVersion]&search[metadata][GIF:BackgroundColor]=0

app/logical/concerns/searchable.rb

@@ -125,6 +125,30 @@ module Searchable
     where_operator(qualified_column, *range)
   end
 
+  # @param attr [String] the name of the JSON field
+  # @param hash [Hash] the hash of values it should contain
+  def where_json_contains(attr, hash)
+    # XXX Hack to transform strings to numbers. Needed to match numeric JSON
+    # values when given string input values from an URL.
+    hash = hash.transform_values do |value|
+      if Integer(value, exception: false)
+        value.to_i
+      elsif Float(value, exception: false)
+        value.to_f
+      else
+        value
+      end
+    end
+
+    where("#{qualified_column_for(attr)} @> :hash", hash: hash.to_json)
+  end
+
+  # @param attr [String] the name of the JSON field
+  # @param hash [String] the key it should contain
+  def where_json_has_key(attr, key)
+    where("#{qualified_column_for(attr)} ? :key", key: key)
+  end
+
   def search_boolean_attribute(attr, params)
     if params[attr].present?
       boolean_attribute_matches(attr, params[attr])
@@ -218,6 +242,8 @@ module Searchable
       search_inet_attribute(name, params)
     when :enum
       search_enum_attribute(name, params)
+    when :jsonb
+      search_jsonb_attribute(name, params)
     when :array
       search_array_attribute(name, subtype, params)
     else
@@ -406,6 +432,26 @@ module Searchable
     relation
   end
 
+  def search_jsonb_attribute(name, params)
+    relation = all
+
+    if params[name].present?
+      relation = relation.where_json_contains(:metadata, params[name])
+    end
+
+    if params["#{name}_has_key"]
+      relation = relation.where_json_has_key(:metadata, params["#{name}_has_key"])
+    end
+
+    if params["has_#{name}"].to_s.truthy?
+      relation = relation.where.not(name => "{}")
+    elsif params["has_#{name}"].to_s.falsy?
+      relation = relation.where(name => "{}")
+    end
+
+    relation
+  end
+
   def search_array_attribute(name, type, params)
     relation = all
     singular_name = name.to_s.singularize

app/logical/upload_service/utils.rb

@@ -63,7 +63,7 @@ class UploadService
 
       process_resizes(upload, file, original_post_id)
 
-      MediaAsset.create_from_media_file!(media_file)
+      MediaAsset.create!(file: media_file)
     end
 
     def automatic_tags(media_file)

app/models/media_asset.rb

@@ -1,20 +1,20 @@
 class MediaAsset < ApplicationRecord
   has_one :media_metadata, dependent: :destroy
 
-  def self.create_from_media_file!(media_file)
-    create!(
-      md5: media_file.md5,
-      file_ext: media_file.file_ext,
-      file_size: media_file.file_size,
-      image_width: media_file.width,
-      image_height: media_file.height,
-      media_metadata: MediaMetadata.new(metadata: media_file.metadata),
-    )
-  end
-
   def self.search(params)
     q = search_attributes(params, :id, :created_at, :updated_at, :md5, :file_ext, :file_size, :image_width, :image_height)
     q = q.apply_default_order(params)
     q
   end
+
+  def file=(file_or_path)
+    media_file = file_or_path.is_a?(MediaFile) ? file_or_path : MediaFile.open(file_or_path)
+
+    self.md5 = media_file.md5
+    self.file_ext = media_file.file_ext
+    self.file_size = media_file.file_size
+    self.image_width = media_file.width
+    self.image_height = media_file.height
+    self.media_metadata = MediaMetadata.new(file: media_file)
+  end
 end

app/models/media_metadata.rb

@@ -15,8 +15,12 @@ class MediaMetadata < ApplicationRecord
   belongs_to :media_asset
 
   def self.search(params)
-    q = search_attributes(params, :id, :created_at, :updated_at, :media_asset_id)
+    q = search_attributes(params, :id, :created_at, :updated_at, :media_asset, :metadata)
     q = q.apply_default_order(params)
     q
   end
+
+  def file=(file_or_path)
+    self.metadata = MediaFile.open(file_or_path).metadata
+  end
 end

test/functional/media_metadata_controller_test.rb

@@ -9,6 +9,26 @@ class MediaMetadataControllerTest < ActionDispatch::IntegrationTest
 
         assert_response :success
       end
+
+      context "searching" do
+        setup do
+          @jpg = create(:media_metadata, file: "test/files/test.jpg")
+          @gif = create(:media_metadata, file: "test/files/test.gif")
+          @png = create(:media_metadata, file: "test/files/test.png")
+        end
+
+        should respond_to_search(has_metadata: true).with { [@png, @gif, @jpg] }
+
+        should respond_to_search(metadata_has_key: "File:ColorComponents").with { [@jpg] }
+        should respond_to_search(metadata: { "File:ColorComponents": 3 }).with { [@jpg] }
+        should respond_to_search(metadata: { "File:ColorComponents": "3" }).with { [@jpg] }
+
+        should respond_to_search(metadata_has_key: "GIF:GIFVersion").with { [@gif] }
+        should respond_to_search(metadata: { "GIF:GIFVersion": "89a" }).with { [@gif] }
+
+        should respond_to_search(metadata_has_key: "PNG:ColorType").with { [@png] }
+        should respond_to_search(metadata: { "PNG:ColorType": "RGB" }).with { [@png] }
+      end
     end
   end
 end