Adds support for relative url root (#138)

* Adds support for relative url root

* Creates base compiler class to hold url prefix

benchmarks/css_asset_urls

@@ -9,19 +9,19 @@ require "open-uri"
 require_relative "./trackrod"
 require_relative "../lib/propshaft"
 require_relative "../lib/propshaft/compilers"
-require_relative "../lib/propshaft/compilers/css_asset_urls"
+require_relative "../lib/propshaft/compiler/css_asset_urls"
 
 trackrod = Trackrod.new(Dir.mktmpdir)
 trackrod.build
 
 assets = ActiveSupport::OrderedOptions.new
 assets.paths     = [ trackrod.root ]
 assets.prefix    = "/assets"
-assets.compilers = [ [ "text/css", Propshaft::Compilers::CssAssetUrls ] ]
+assets.compilers = [ [ "text/css", Propshaft::Compiler::CssAssetUrls ] ]
 
 assembly = Propshaft::Assembly.new(assets)
 asset    = assembly.load_path.find(trackrod.assets.css)
-compiler = Propshaft::Compilers::CssAssetUrls.new(assembly)
+compiler = Propshaft::Compiler::CssAssetUrls.new(assembly)
 
 Benchmark.ips do |x|
   x.config(time: 5, warmup: 2)

benchmarks/dynamic_resolver

@@ -15,7 +15,7 @@ trackrod.build
 assets = ActiveSupport::OrderedOptions.new
 assets.paths         = [ trackrod.root ]
 assets.prefix        = "/assets"
-assets.compilers     = [ [ "text/css", Propshaft::Compilers::CssAssetUrls ] ]
+assets.compilers     = [ [ "text/css", Propshaft::Compiler::CssAssetUrls ] ]
 assets.output_path ||= Pathname.new(Dir.mktmpdir)
 
 assembly = Propshaft::Assembly.new(assets)

benchmarks/static_resolver

@@ -15,7 +15,7 @@ trackrod.build
 assets = ActiveSupport::OrderedOptions.new
 assets.paths         = [ trackrod.root ]
 assets.prefix        = "/assets"
-assets.compilers     = [ [ "text/css", Propshaft::Compilers::CssAssetUrls ] ]
+assets.compilers     = [ [ "text/css", Propshaft::Compiler::CssAssetUrls ] ]
 assets.output_path ||= Pathname.new(Dir.mktmpdir)
 
 assembly = Propshaft::Assembly.new(assets)

lib/propshaft/assembly.rb

@@ -4,8 +4,8 @@
 require "propshaft/server"
 require "propshaft/processor"
 require "propshaft/compilers"
-require "propshaft/compilers/css_asset_urls"
-require "propshaft/compilers/source_mapping_urls"
+require "propshaft/compiler/css_asset_urls"
+require "propshaft/compiler/source_mapping_urls"
 
 class Propshaft::Assembly
   attr_reader :config

lib/propshaft/compiler.rb

@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+# Base compiler from which other compilers can inherit
+class Propshaft::Compiler
+  attr_reader :assembly
+
+  def initialize(assembly)
+    @assembly = assembly
+  end
+
+  # Override this in a specific compiler
+  def compile(logical_path, input)
+    raise NotImplementedError
+  end
+
+  private
+    def url_prefix
+      @url_prefix ||= File.join(assembly.config.relative_url_root.to_s, assembly.config.prefix.to_s).chomp("/")
+    end
+end

lib/propshaft/compilers/css_asset_urls.rb → lib/propshaft/compiler/css_asset_urls.rb

@@ -1,14 +1,10 @@
 # frozen_string_literal: true
 
-class Propshaft::Compilers::CssAssetUrls
-  attr_reader :assembly
+require "propshaft/compiler"
 
+class Propshaft::Compiler::CssAssetUrls < Propshaft::Compiler
   ASSET_URL_PATTERN = /url\(\s*["']?(?!(?:\#|%23|data|http|\/\/))([^"'\s?#)]+)([#?][^"')]+)?\s*["']?\)/
 
-  def initialize(assembly)
-    @assembly = assembly
-  end
-
   def compile(logical_path, input)
     input.gsub(ASSET_URL_PATTERN) { asset_url resolve_path(logical_path.dirname, $1), logical_path, $2, $1 }
   end
@@ -26,7 +22,7 @@ def resolve_path(directory, filename)
 
     def asset_url(resolved_path, logical_path, fingerprint, pattern)
       if asset = assembly.load_path.find(resolved_path)
-        %[url("#{assembly.config.prefix}/#{asset.digested_path}#{fingerprint}")]
+        %[url("#{url_prefix}/#{asset.digested_path}#{fingerprint}")]
       else
         Propshaft.logger.warn "Unable to resolve '#{pattern}' for missing asset '#{resolved_path}' in #{logical_path}"
         %[url("#{pattern}")]

lib/propshaft/compilers/source_mapping_urls.rb → lib/propshaft/compiler/source_mapping_urls.rb

@@ -1,14 +1,10 @@
 # frozen_string_literal: true
 
-class Propshaft::Compilers::SourceMappingUrls
-  attr_reader :assembly
+require "propshaft/compiler"
 
+class Propshaft::Compiler::SourceMappingUrls < Propshaft::Compiler
   SOURCE_MAPPING_PATTERN = %r{^(//|/\*)# sourceMappingURL=(.+\.map)}
 
-  def initialize(assembly)
-    @assembly = assembly
-  end
-
   def compile(logical_path, input)
     input.gsub(SOURCE_MAPPING_PATTERN) { source_mapping_url(asset_path($2, logical_path), $1) }
   end
@@ -24,7 +20,7 @@ def asset_path(source_mapping_url, logical_path)
 
     def source_mapping_url(resolved_path, comment)
       if asset = assembly.load_path.find(resolved_path)
-        "#{comment}# sourceMappingURL=#{assembly.config.prefix}/#{asset.digested_path}"
+        "#{comment}# sourceMappingURL=#{url_prefix}/#{asset.digested_path}"
       else
         Propshaft.logger.warn "Removed sourceMappingURL comment for missing asset '#{resolved_path}' from #{resolved_path}"
         comment

lib/propshaft/railtie.rb

@@ -11,12 +11,13 @@ class Railtie < ::Rails::Railtie
     config.assets.prefix         = "/assets"
     config.assets.quiet          = false
     config.assets.compilers      = [
-      [ "text/css", Propshaft::Compilers::CssAssetUrls ],
-      [ "text/css", Propshaft::Compilers::SourceMappingUrls ],
-      [ "text/javascript", Propshaft::Compilers::SourceMappingUrls ]
+      [ "text/css", Propshaft::Compiler::CssAssetUrls ],
+      [ "text/css", Propshaft::Compiler::SourceMappingUrls ],
+      [ "text/javascript", Propshaft::Compiler::SourceMappingUrls ]
     ]
     config.assets.sweep_cache = Rails.env.development?
     config.assets.server = Rails.env.development? || Rails.env.test?
+    config.assets.relative_url_root = nil
 
     # Register propshaft initializer to copy the assets path in all the Rails Engines.
     # This makes possible for us to keep all `assets` config in this Railtie, but still
@@ -30,6 +31,7 @@ class Railtie < ::Rails::Railtie
     end
 
     config.after_initialize do |app|
+      config.assets.relative_url_root ||= app.config.relative_url_root
       config.assets.output_path ||=
         Pathname.new(File.join(app.config.paths["public"].first, app.config.assets.prefix))
 

test/propshaft/compilers/css_asset_urls_test.rb → test/propshaft/compiler/css_asset_urls_test.rb

@@ -4,15 +4,13 @@
 require "propshaft/assembly"
 require "propshaft/compilers"
 
-class Propshaft::Compilers::CssAssetUrlsTest < ActiveSupport::TestCase
+class Propshaft::Compiler::CssAssetUrlsTest < ActiveSupport::TestCase
   setup do
-    @assembly = Propshaft::Assembly.new(ActiveSupport::OrderedOptions.new.tap { |config|
+    @options = ActiveSupport::OrderedOptions.new.tap { |config|
       config.paths = [ Pathname.new("#{__dir__}/../../fixtures/assets/vendor") ]
       config.output_path = Pathname.new("#{__dir__}/../../fixtures/output")
       config.prefix = "/assets"
-    })
-
-    @assembly.compilers.register "text/css", Propshaft::Compilers::CssAssetUrls
+    }
   end
 
   test "basic" do
@@ -120,14 +118,23 @@ class Propshaft::Compilers::CssAssetUrlsTest < ActiveSupport::TestCase
     assert_match(/{ background: url\("file-not-found.jpg"\); }/, compiled)
   end
 
+  test "relative url root" do
+    @options.relative_url_root = "/url-root"
+
+    compiled = compile_asset_with_content(%({ background: url(file.jpg); }))
+    assert_match(/{ background: url\("\/url-root\/assets\/foobar\/source\/file-[a-z0-9]{40}.jpg"\); }/, compiled)
+  end
+
   private
     def compile_asset_with_content(content)
       root_path    = Pathname.new("#{__dir__}/../../fixtures/assets/vendor")
       logical_path = "foobar/source/test.css"
 
       asset     = Propshaft::Asset.new(root_path.join(logical_path), logical_path: logical_path)
       asset.stub :content, content do
-        @assembly.compilers.compile(asset)
+        assembly = Propshaft::Assembly.new(@options)
+        assembly.compilers.register "text/css", Propshaft::Compiler::CssAssetUrls
+        assembly.compilers.compile(asset)
       end
     end
 end

test/propshaft/compiler/source_mapping_urls_test.rb

@@ -0,0 +1,66 @@
+require "test_helper"
+require "minitest/mock"
+require "propshaft/asset"
+require "propshaft/assembly"
+require "propshaft/compilers"
+
+class Propshaft::Compiler::SourceMappingUrlsTest < ActiveSupport::TestCase
+  setup do
+    @options = ActiveSupport::OrderedOptions.new.tap { |config|
+      config.paths = [ Pathname.new("#{__dir__}/../../fixtures/assets/mapped") ]
+      config.output_path = Pathname.new("#{__dir__}/../../fixtures/output")
+      config.prefix = "/assets"
+    }
+  end
+
+  test "matching source map" do
+    assert_match %r{//# sourceMappingURL=/assets/source.js-[a-z0-9]{40}\.map},
+                 compile_asset(find_asset("source.js", fixture_path: "mapped"))
+    assert_match %r{/\*# sourceMappingURL=/assets/source.css-[a-z0-9]{40}\.map},
+                 compile_asset(find_asset("source.css", fixture_path: "mapped"))
+  end
+
+  test "matching nested source map" do
+    assert_match %r{//# sourceMappingURL=/assets/nested/another-source.js-[a-z0-9]{40}\.map},
+                 compile_asset(find_asset("nested/another-source.js", fixture_path: "mapped"))
+  end
+
+  test "missing source map" do
+    assert_no_match %r{sourceMappingURL},
+                    compile_asset(find_asset("sourceless.js", fixture_path: "mapped"))
+    assert_no_match %r{sourceMappingURL},
+                    compile_asset(find_asset("sourceless.css", fixture_path: "mapped"))
+  end
+
+  test "sourceMappingURL removal due to missing map does not damage /* ... */ comments" do
+    assert_match %r{\A#{Regexp.escape ".failure { color: red; }\n/* */\n"}\Z},
+                 compile_asset(find_asset("sourceless.css", fixture_path: "mapped"))
+  end
+
+  test "sourceMappingURL outside of a comment should be left alone" do
+    assert_match %r{sourceMappingURL=sourceMappingURL-outside-comment.css.map},
+                 compile_asset(find_asset("sourceMappingURL-outside-comment.css", fixture_path: "mapped"))
+  end
+
+  test "sourceMappingURL not at the beginning of the line should be left alone" do
+    assert_match %r{sourceMappingURL=sourceMappingURL-not-at-start.css.map},
+                 compile_asset(find_asset("sourceMappingURL-not-at-start.css", fixture_path: "mapped"))
+  end
+
+  test "relative url root" do
+    @options.relative_url_root = "/url-root"
+
+    assert_match %r{//# sourceMappingURL=/url-root/assets/source.js-[a-z0-9]{40}\.map},
+                  compile_asset(find_asset("source.js", fixture_path: "mapped"))
+  end
+
+  private
+    def compile_asset(asset)
+
+      assembly = Propshaft::Assembly.new(@options)
+      assembly.compilers.register "text/javascript", Propshaft::Compiler::SourceMappingUrls
+      assembly.compilers.register "text/css", Propshaft::Compiler::SourceMappingUrls
+
+      assembly.compilers.compile(asset)
+    end
+end

test/propshaft/compilers_test.rb

@@ -13,7 +13,7 @@ class Propshaft::CompilersTest < ActiveSupport::TestCase
   end
 
   test "replace asset-path function in css with digested url" do
-    @assembly.compilers.register "text/css", Propshaft::Compilers::CssAssetUrls
+    @assembly.compilers.register "text/css", Propshaft::Compiler::CssAssetUrls
     assert_match(/"\/assets\/archive-[a-z0-9]{40}.svg/, @assembly.compilers.compile(find_asset("another.css")))
   end
 

test/propshaft/server_test.rb

@@ -11,7 +11,7 @@ class Propshaft::ServerTest < ActiveSupport::TestCase
       config.output_path = Pathname.new("#{__dir__}../fixtures/output")
     })
 
-    @assembly.compilers.register "text/css", Propshaft::Compilers::CssAssetUrls
+    @assembly.compilers.register "text/css", Propshaft::Compiler::CssAssetUrls
     @server = Propshaft::Server.new(@assembly)
   end