Task to import Scratch assets

We have permission from the Scratch Foundation to use the library assets available with Scratch.

These tasks imports them assets defined in the in the library configuration files. See [1] for instructions on how to run.

RaspberryPiFoundation/digital-editor-issues#1229

Author: zetter-rpf

.env.example

@@ -62,3 +62,6 @@ SALESFORCE_CONNECT_PORT=5432
 SALESFORCE_CONNECT_DB=salesforce_development
 SALESFORCE_CONNECT_PASSWORD=password
 SALESFORCE_CONNECT_USER=postgres
+
+SCRATCH_ASSET_CONFIG_BASE_URL=https://example.com/config/
+SCRATCH_ASSET_IMPORT_BASE_URL=https://example.com/assets/

lib/scratch_asset_importer.rb

@@ -0,0 +1,37 @@
+require 'ruby-progressbar'
+
+class ScratchAssetImporter
+  def self.import(...)
+    new(...).import
+  end
+
+  attr_reader :asset_base_url, :asset_names
+
+  def initialize(asset_names, asset_base_url)
+    @asset_names = asset_names
+    @asset_base_url = asset_base_url
+  end
+
+  def import
+    asset_names.each do |asset_name|
+      import_asset(asset_name)
+    end
+  end
+
+  private
+
+  def import_asset(asset_name)
+    return if ScratchAsset.exists?(filename: asset_name)
+
+    asset = connection.get("#{asset_name}/get/")
+    ScratchAsset.create!(filename: asset_name).file.attach(io: StringIO.new(asset.body), filename: asset_name)
+  rescue StandardError => e
+    Rails.logger.error("Failed to import asset #{asset_name}: #{e.message}")
+  end
+
+  def connection
+    @connection ||= Faraday.new(url: asset_base_url) do |faraday|
+      faraday.response :raise_error
+    end
+  end
+end

lib/scratch_config_importer.rb

@@ -0,0 +1,33 @@
+require 'ruby-progressbar'
+
+class ScratchConfigImporter
+  def self.import(...)
+    new(...).import
+  end
+
+  attr_reader :asset_base_url, :asset_config_url
+
+  def initialize(asset_config_url, asset_base_url)
+    @asset_config_url = asset_config_url
+    @asset_base_url = asset_base_url
+  end
+
+  def import
+    config = Faraday.get(asset_config_url).body
+    asset_config = JSON.parse(config, symbolize_names: true)
+    asset_names = extract_asset_names(asset_config)
+    ScratchAssetImporter.import(asset_names, asset_base_url)
+  end
+
+  private
+
+  def extract_asset_names(config)
+    names = []
+    config.each do |item|
+      names << item[:md5ext] if item[:md5ext]
+      names.concat(extract_asset_names(item.fetch(:costumes, [])))
+      names.concat(extract_asset_names(item.fetch(:sounds, [])))
+    end
+    names
+  end
+end

lib/tasks/scratch_assets.rake

@@ -0,0 +1,38 @@
+require_relative 'seeds_helper'
+
+namespace :scratch_assets do
+  desc 'Import scratch assets'
+  task import_all: %i[import_backdrops import_costumes import_sounds import_sprites]
+
+  task import_backdrops: :environment do
+    Rails.logger.info 'Importing backdrops...'
+    config_url = "#{config_base_url}backdrops.json"
+    ScratchConfigImporter.import(config_url, import_base_url)
+  end
+
+  task import_costumes: :environment do
+    Rails.logger.info 'Importing costumes...'
+    config_url = "#{config_base_url}costumes.json"
+    ScratchConfigImporter.import(config_url, import_base_url)
+  end
+
+  task import_sounds: :environment do
+    Rails.logger.info 'Importing sounds...'
+    config_url = "#{config_base_url}sounds.json"
+    ScratchConfigImporter.import(config_url, import_base_url)
+  end
+
+  task import_sprites: :environment do
+    Rails.logger.info 'Importing sprites...'
+    config_url = "#{config_base_url}sprites.json"
+    ScratchConfigImporter.import(config_url, import_base_url)
+  end
+
+  def config_base_url
+    ENV.fetch('SCRATCH_ASSET_CONFIG_BASE_URL')
+  end
+
+  def import_base_url
+    ENV.fetch('SCRATCH_ASSET_IMPORT_BASE_URL')
+  end
+end

spec/lib/scratch_asset_importer_spec.rb

@@ -0,0 +1,50 @@
+# frozen_string_literal: true
+
+#
+require 'rails_helper'
+require 'scratch_asset_importer'
+
+RSpec.describe ScratchAssetImporter do
+  describe '.import' do
+    it 'imports assets from the config' do
+      image = Rails.root.join('spec/fixtures/files/test_image_1.png').read
+      stub_request(:get, 'https://example.net/internalapi/asset/123abc.png/get/').to_return(status: 200, body: image)
+
+      described_class.import(['123abc.png'], 'https://example.net/internalapi/asset/')
+
+      scratch_asset = ScratchAsset.find_by(filename: '123abc.png')
+      expect(scratch_asset).to be_present
+      expect(scratch_asset.file.download).to eq(image)
+    end
+
+    it 'does nothing if asset already exists' do
+      create(:scratch_asset, :with_file, filename: '123abc.png')
+
+      expect do
+        described_class.import(['123abc.png'], 'https://example.net/internalapi/asset/')
+      end.not_to change(ScratchAsset, :count)
+    end
+
+    it 'can import multiple assets' do
+      image = Rails.root.join('spec/fixtures/files/test_image_1.png').read
+
+      stub_request(:get, 'https://example.net/internalapi/asset/123abc.png/get/').to_return(status: 200, body: image)
+      stub_request(:get, 'https://example.net/internalapi/asset/456xyz.png/get/').to_return(status: 200, body: image)
+
+      described_class.import(['123abc.png', '456xyz.png'], 'https://example.net/internalapi/asset/')
+      expect(ScratchAsset.find_by(filename: '123abc.png')).to be_present
+      expect(ScratchAsset.find_by(filename: '456xyz.png')).to be_present
+    end
+
+    it 'skips assets that fail to import' do
+      image = Rails.root.join('spec/fixtures/files/test_image_1.png').read
+
+      stub_request(:get, 'https://example.net/internalapi/asset/123abc.png/get/').to_return(status: 500, body: 'error')
+      stub_request(:get, 'https://example.net/internalapi/asset/456xyz.png/get/').to_return(status: 200, body: image)
+
+      described_class.import(['123abc.png', '456xyz.png'], 'https://example.net/internalapi/asset/')
+      expect(ScratchAsset.find_by(filename: '123abc.png')).not_to be_present
+      expect(ScratchAsset.find_by(filename: '456xyz.png')).to be_present
+    end
+  end
+end

spec/lib/scratch_config_importer_spec.rb

@@ -0,0 +1,40 @@
+# frozen_string_literal: true
+
+#
+require 'rails_helper'
+require 'scratch_asset_importer'
+
+RSpec.describe ScratchConfigImporter do
+  before do
+    allow(ScratchAssetImporter).to receive(:import)
+  end
+
+  describe '.import' do
+    it 'imports assets from the config' do
+      config = [{ md5ext: '123abc.png' }].to_json
+      stub_request(:get, 'https://example.com/config/backdrops.json').to_return(status: 200, body: config)
+
+      described_class.import('https://example.com/config/backdrops.json', 'https://example.net/internalapi/asset/')
+
+      expect(ScratchAssetImporter).to have_received(:import).with(['123abc.png'], 'https://example.net/internalapi/asset/')
+    end
+
+    it 'handles assets nested under sounds and costumes' do
+      config = [
+        {
+          costumes: [{
+            md5ext: '123abc.png'
+          }],
+          sounds: [{
+            md5ext: '456xyz.png'
+          }]
+        }
+      ].to_json
+      stub_request(:get, 'https://example.com/config/sprites.json').to_return(status: 200, body: config)
+
+      described_class.import('https://example.com/config/sprites.json', 'https://example.net/internalapi/asset/')
+
+      expect(ScratchAssetImporter).to have_received(:import).with(['123abc.png', '456xyz.png'], 'https://example.net/internalapi/asset/')
+    end
+  end
+end