Merge EmberCLI-generated Manifest with Sprockets'

Closes [#298]

Expose Ember's fingerprinted assets to Sprockets.

[#298]: #298

app/helpers/ember_rails_helper.rb

@@ -20,10 +20,10 @@ def render_ember_app(name, &block)
   end
 
   def include_ember_script_tags(name, **options)
-    javascript_include_tag(*EmberCli[name].sprockets.assets, options)
+    javascript_include_tag(*EmberCli[name].sprockets.javascript_assets, options)
   end
 
   def include_ember_stylesheet_tags(name, **options)
-    stylesheet_link_tag(*EmberCli[name].sprockets.assets, options)
+    stylesheet_link_tag(*EmberCli[name].sprockets.stylesheet_assets, options)
   end
 end

gemfiles/3.2.gemfile

@@ -3,7 +3,6 @@
 source "https://rubygems.org"
 
 gem "appraisal"
-gem "test-unit", "~> 3.0"
 gem "rails", :git => "https://github.com/rails/rails.git", :branch => "3-2-stable"
 gem "pry"
 

lib/ember_cli/app.rb

@@ -34,6 +34,7 @@ def compile
         @shell.compile
         @build.check!
         copy_index_html_file
+        sprockets.update_manifest!
         true
       end
     end
@@ -82,6 +83,7 @@ def build_and_watch
       prepare
       @shell.build_and_watch
       copy_index_html_file
+      sprockets.update_manifest!
     end
 
     def prepare

lib/ember_cli/assets.rb

@@ -0,0 +1,97 @@
+module EmberCli
+  class Assets
+    def initialize(app_name:, ember_app_name:, manifest:)
+      @app_name = app_name
+      @ember_app_name = ember_app_name
+      @manifest = manifest
+    end
+
+    def javascripts
+      if empty_manifest?
+        fallback_assets
+      else
+        [latest_vendor_js, latest_app_js]
+      end
+    end
+
+    def stylesheets
+      if empty_manifest?
+        fallback_assets
+      else
+        [latest_vendor_css, latest_app_css]
+      end
+    end
+
+    private
+
+    attr_reader :app_name, :ember_app_name, :environment, :manifest
+
+    def vendor_js_files
+      regex = %r{#{app_name}/assets/vendor(.*)\.js\z}
+      files.select { |key| key =~ regex }
+    end
+
+    def latest_vendor_js
+      asset_name, _ = vendor_js_files.
+        sort_by { |_, data| data["mtime"] }.
+        reverse.
+        first
+
+      asset_name
+    end
+
+    def app_js_files
+      regex = %r{#{app_name}/assets/#{ember_app_name}(.*)\.js\z}
+      files.select { |key| key =~ regex }
+    end
+
+    def latest_app_js
+      asset_name, _ = app_js_files.
+        sort_by { |_, data| data["mtime"] }.
+        reverse.
+        first
+
+      asset_name
+    end
+
+    def vendor_css_files
+      regex = %r{#{app_name}/assets/vendor(.*)\.css\z}
+      files.select { |key| key =~ regex }
+    end
+
+    def latest_vendor_css
+      asset_name, _ = vendor_css_files.
+        sort_by { |_, data| data["mtime"] }.
+        reverse.
+        first
+
+      asset_name
+    end
+
+    def app_css_files
+      regex = %r{#{app_name}/assets/#{ember_app_name}(.*)\.css\z}
+      files.select { |key| key =~ regex }
+    end
+
+    def latest_app_css
+      asset_name, _ = app_css_files.
+        sort_by { |_, data| data["mtime"] }.
+        reverse.
+        first
+
+      asset_name
+    end
+
+    def files
+      manifest.files
+    end
+
+    def empty_manifest?
+      files.empty?
+    end
+
+    def fallback_assets
+      ["#{app_name}/assets/vendor", "#{app_name}/assets/#{ember_app_name}"]
+    end
+  end
+end

lib/ember_cli/manifest.rb

@@ -0,0 +1,14 @@
+require "sprockets"
+
+module EmberCli
+  class Manifest
+    def initialize(environment, path)
+      @manifest = ::Sprockets::Manifest.new(environment, path)
+    end
+
+    def merge_into!(other)
+      other.assets.merge!(@manifest.assets)
+      other.files.merge!(@manifest.files)
+    end
+  end
+end

lib/ember_cli/path_set.rb

@@ -75,6 +75,10 @@ def build_error_file
       @build_error_file ||= tmp.join("error.txt")
     end
 
+    def manifest
+      manifests.first
+    end
+
     def bower
       @bower ||= begin
         bower_path = app_options.fetch(:bower_path) { configuration.bower_path }
@@ -109,6 +113,10 @@ def bundler
 
     delegate :name, :options, to: :app, prefix: true
 
+    def manifests
+      Pathname.glob(app_assets.join("assets", "manifest*.json"))
+    end
+
     def default_root
       rails_root.join(app_name)
     end

lib/ember_cli/sprockets.rb

@@ -1,6 +1,8 @@
 require "ember_cli/errors"
 require "non-stupid-digest-assets"
 require "ember_cli/html_page"
+require "ember_cli/manifest"
+require "ember_cli/assets"
 
 module EmberCli
   class Sprockets
@@ -14,6 +16,10 @@ def register!
       register_or_raise!(NonStupidDigestAssets.whitelist)
     end
 
+    def update_manifest!
+      ember_manifest.merge_into!(rails_manifest)
+    end
+
     def index_html(head:, body:)
       html_page = HtmlPage.new(
         content: app.index_file.read,
@@ -24,14 +30,26 @@ def index_html(head:, body:)
       html_page.render
     end
 
-    def assets
-      ["#{app.name}/assets/vendor", "#{app.name}/assets/#{ember_app_name}"]
+    def javascript_assets
+      assets.javascripts
+    end
+
+    def stylesheet_assets
+      assets.stylesheets
     end
 
     private
 
     attr_reader :app
 
+    def assets
+      Assets.new(
+        app_name: app.name,
+        ember_app_name: ember_app_name,
+        manifest: rails_manifest,
+      )
+    end
+
     def ember_app_name
       @ember_app_name ||= app.options.fetch(:name) { package_json.fetch(:name) }
     end
@@ -41,6 +59,14 @@ def package_json
         JSON.parse(app.paths.package_json_file.read).with_indifferent_access
     end
 
+    def ember_manifest
+      @ember_manifest ||= Manifest.new(Rails.env, app.paths.manifest)
+    end
+
+    def rails_manifest
+      Rails.application.assets_manifest
+    end
+
     def asset_matcher
       %r{\A#{app.name}/}
     end

spec/lib/ember_cli/assets_spec.rb

@@ -0,0 +1,125 @@
+require "ember_cli/assets"
+
+describe EmberCli::Assets do
+  describe "#javascripts" do
+    it "includes the most recent javascript build artifacts" do
+      manifest = build_manifest(
+        files: {
+          "foo/assets/bar-abc123.js" => {
+            "logical_path" => "vendor.js",
+            "mtime" => 1.day.ago.iso8601,
+          },
+          "foo/assets/bar-def456.js" => {
+            "logical_path" => "vendor.js",
+            "mtime" => 2.days.ago.iso8601,
+          },
+          "foo/assets/vendor-abc123.js" => {
+            "logical_path" => "vendor.js",
+            "mtime" => 1.day.ago.iso8601,
+          },
+          "foo/assets/vendor-def456.js" => {
+            "logical_path" => "vendor.js",
+            "mtime" => 2.days.ago.iso8601,
+          },
+          "not-a-match" => {},
+        }
+      )
+      assets = build_assets(
+        app_name: "foo",
+        ember_app_name: "bar",
+        manifest: manifest,
+      )
+
+      javascripts = assets.javascripts
+
+      expect(javascripts).to match_array([
+        "foo/assets/bar-abc123.js",
+        "foo/assets/vendor-abc123.js",
+      ])
+    end
+
+    context "when the manifest is empty" do
+      it "falls back to the default assets" do
+        assets = build_assets(
+          manifest: build_empty_manifest,
+          app_name: "foo",
+          ember_app_name: "bar",
+        )
+
+        javascripts = assets.javascripts
+
+        expect(javascripts).to match_array([
+          "foo/assets/vendor",
+          "foo/assets/bar",
+        ])
+      end
+    end
+  end
+
+  describe "#stylesheets" do
+    it "includes the most recent stylesheet build artifacts" do
+      manifest = build_manifest(
+        files: {
+          "foo/assets/bar-abc123.css" => {
+            "logical_path" => "vendor.css",
+            "mtime" => 1.day.ago.iso8601,
+          },
+          "foo/assets/bar-def456.css" => {
+            "logical_path" => "vendor.css",
+            "mtime" => 2.days.ago.iso8601,
+          },
+          "foo/assets/vendor-abc123.css" => {
+            "logical_path" => "vendor.css",
+            "mtime" => 1.day.ago.iso8601,
+          },
+          "foo/assets/vendor-def456.css" => {
+            "logical_path" => "vendor.css",
+            "mtime" => 2.days.ago.iso8601,
+          },
+          "not-a-match" => {},
+        }
+      )
+      assets = build_assets(
+        app_name: "foo",
+        ember_app_name: "bar",
+        manifest: manifest,
+      )
+
+      stylesheets = assets.stylesheets
+
+      expect(stylesheets).to match_array([
+        "foo/assets/bar-abc123.css",
+        "foo/assets/vendor-abc123.css",
+      ])
+    end
+
+    context "when the manifest is empty" do
+      it "falls back to the default assets" do
+        assets = build_assets(
+          manifest: build_empty_manifest,
+          app_name: "foo",
+          ember_app_name: "bar",
+        )
+
+        stylesheets = assets.stylesheets
+
+        expect(stylesheets).to match_array([
+          "foo/assets/vendor",
+          "foo/assets/bar",
+        ])
+      end
+    end
+  end
+end
+
+def build_assets(manifest: build_manifest, **options)
+  EmberCli::Assets.new(options.merge(manifest: manifest))
+end
+
+def build_manifest(files: {})
+  double(files: files)
+end
+
+def build_empty_manifest
+  build_manifest
+end

spec/lib/ember_cli/manifest_spec.rb

@@ -0,0 +1,31 @@
+require "ember_cli/manifest"
+
+describe EmberCli::Manifest do
+  describe "#merge_into!" do
+    it "merges the manifest into the provided manifest" do
+      manifest_file = create_json_file(
+        "assets" => {
+          "asset" => "path/to/asset.js",
+        },
+        "files" => {
+          "file" => "path/to/file.js",
+        },
+      )
+      manifest = EmberCli::Manifest.new("test", manifest_file.path)
+      rails_manifest = OpenStruct.new(assets: {}, files: {})
+
+      manifest.merge_into!(rails_manifest)
+
+      expect(rails_manifest.assets).to eq("asset" => "path/to/asset.js")
+      expect(rails_manifest.files).to eq("file" => "path/to/file.js")
+    end
+  end
+
+  def create_json_file(json)
+    tempfile = Tempfile.new("json")
+    tempfile.write(JSON.dump(json))
+    tempfile.close
+
+    tempfile
+  end
+end