Optional manifest_path config

README.md

@@ -39,6 +39,7 @@ Below is the default configuration showing all available options;
 activate :imageoptim do |options|
   # Use a build manifest to prevent re-compressing images between builds
   options.manifest = true
+  options.manifest_path = './build/'
 
   # Silence problematic image_optim workers
   options.skip_missing_workers = true

features/manifest.feature

@@ -4,7 +4,15 @@ Feature: Manifest
     Given a successfully built app at "basic-app" with flags "--verbose"
     Then the following files should exist:
       | build/imageoptim.manifest.yml |
-    Then the manifest should have the right timestamp for "build/images/table.jpg"
+    Then the manifest at "build" should have the right timestamp for "build/images/table.jpg"
+
+  Scenario: Save manifest at custom path
+    Given a fixture app "basic-app"
+    And app "basic-app" is using config "custom-manifest-path"
+    Given a successfully built app at "basic-app" with flags "--verbose"
+    Then the following files should exist:
+      | custom/manifest/path/imageoptim.manifest.yml |
+    Then the manifest at "custom/manifest/path" should have the right timestamp for "build/images/table.jpg"
 
   Scenario: Don't write a manifest file if it is disabled
     Given a fixture app "basic-app"

features/support/step_definitions.rb

@@ -8,8 +8,8 @@
   expect(File.size(File.join(current_dir, img))).to be < size.to_i
 end
 
-Then(/^the manifest should have the right timestamp for "(.*?)"$/) do |file|
-  manifest = YAML.load(File.read(manifest_path))
+Then(/^the manifest at "(.*?)" should have the right timestamp for "(.*?)"$/) do |manifest_base_path, file|
+  manifest = YAML.load(File.read(manifest_path(manifest_base_path)))
   file_stamp = File.mtime(File.join(current_dir, file))
   expect(manifest[file]).to eql(file_stamp)
 end
@@ -40,6 +40,6 @@
   expect(File.mtime(target)).not_to eql(@modification_times[target])
 end
 
-def manifest_path
-  File.join(current_dir, 'build', 'imageoptim.manifest.yml')
+def manifest_path(manifest_base_path = 'build')
+  File.join(current_dir, manifest_base_path, 'imageoptim.manifest.yml')
 end

fixtures/basic-app/config-custom-manifest-path.rb

@@ -0,0 +1,3 @@
+activate :imageoptim do |options|
+  options.manifest_path = 'custom/manifest/path'
+end

lib/middleman-imageoptim/manifest.rb

@@ -3,14 +3,15 @@ module Imageoptim
     class Manifest
       MANIFEST_FILENAME = 'imageoptim.manifest.yml'.freeze
 
-      attr_reader :app
+      attr_reader :app, :path_option
 
-      def initialize(app)
+      def initialize(app, path_option = nil)
         @app = app
+        @path_option = path_option
       end
 
       def path
-        File.join(build_dir, MANIFEST_FILENAME)
+        @path ||= File.join(base_path, MANIFEST_FILENAME)
       end
 
       def build_dir
@@ -31,18 +32,28 @@ def resource(key)
 
       private
 
+      def base_path
+        if path_option.present?
+          path_option
+        else
+          build_dir
+        end
+      end
+
       def resources
-        @resources ||= load(path)
+        @resources ||= begin
+          if File.exist?(path)
+            YAML.load_file(path)
+          else
+            {}
+          end
+        end
       end
 
       def dump(source)
         YAML.dump(source)
       end
 
-      def load(path)
-        YAML.load(File.read(path))
-      end
-
       def build(resources)
         resources.inject({}) do |new_manifest, resource|
           new_manifest[resource.to_s] = File.mtime(resource)
@@ -51,6 +62,8 @@ def build(resources)
       end
 
       def write(manifest)
+        FileUtils.mkpath(base_path) unless File.exists?(path)
+
         File.open(path, 'w') do |manifest_file|
           manifest_file.write(manifest)
         end

lib/middleman-imageoptim/optimizer.rb

@@ -100,7 +100,7 @@ def optimizer
       end
 
       def manifest
-        @manifest ||= Manifest.new(app)
+        @manifest ||= Manifest.new(app, options.manifest_path)
       end
 
       def update_bytes_saved(bytes)

lib/middleman-imageoptim/options.rb

@@ -6,17 +6,20 @@ class Options
       # Mapping of valid option names to default values
       EXTENSION_OPTIONS = [
         :image_extensions,
-        :manifest
+        :manifest,
+        :manifest_path
       ].freeze
+
       OPTIONS = {
         advpng: { level: 4 },
         allow_lossy: false,
         gifsicle: { interlace: false },
         image_extensions: %w(.png .jpg .jpeg .gif .svg),
         jpegoptim: { strip: ['all'], max_quality: 100 },
         jpegtran: { copy_chunks: false, progressive: true, jpegrescan: true },
-        nice: true,
         manifest: true,
+        manifest_path: nil,
+        nice: true,
         optipng: { level: 6, interlace: false },
         pack: true,
         pngcrush: { chunks: ['alla'], fix: false, brute: false },
@@ -46,8 +49,8 @@ def symbolize_key(key)
       end
 
       def set_options(user_options)
-        OPTIONS.keys.each do |name|
-          instance_variable_set(:"@#{name}", user_options.fetch(name, OPTIONS[name]))
+        OPTIONS.each do |name, default_value|
+          instance_variable_set(:"@#{name}", user_options.fetch(name, default_value))
         end
       end
     end