Added inlineAssets, split out inlineAssetsFromVirtualDirectory

README.md

@@ -6,10 +6,12 @@ the infamous
 and other SEO optimizations that can easily become tedious to perform by hand.
 
 ## `inlineAssets`
-This function is a simple one; it wraps a `VirtualDirectory` to patch the way it sends
+A
-`.html` files.
+[response finalizer](https://angel-dart.gitbook.io/angel/the-basics/request-lifecycle)
+that can be used in any application to patch HTML responses, including those sent with
+a templating engine like Jael.
 
-In any `.html` file sent down, `link` and `script` elements that point to internal resources
+In any `text/html` response sent down, `link` and `script` elements that point to internal resources
 will have the contents of said file read, and inlined into the HTML page itself.
 
 In this case, "internal resources" refers to a URI *without* a scheme, i.e. `/site.css` or
@@ -21,6 +23,32 @@ import 'package:angel_seo/angel_seo.dart';
 import 'package:angel_static/angel_static.dart';
 import 'package:file/local.dart';
 
+main() async {
+  var app = new Angel()..lazyParseBodies = true;
+  var fs = const LocalFileSystem();
+  var http = new AngelHttp(app);
+
+  app.responseFinalizers.add(inlineAssets(fs.directory('web')));
+
+  app.use(() => throw new AngelHttpException.notFound());
+
+  var server = await http.startServer('127.0.0.1', 3000);
+  print('Listening at http://${server.address.address}:${server.port}');
+}
+```
+
+## `inlineAssetsFromVirtualDirectory`
+This function is a simple one; it wraps a `VirtualDirectory` to patch the way it sends
+`.html` files.
+
+Produces the same functionality as `inlineAssets`.
+
+```dart
+import 'package:angel_framework/angel_framework.dart';
+import 'package:angel_seo/angel_seo.dart';
+import 'package:angel_static/angel_static.dart';
+import 'package:file/local.dart';
+
 main() async {
   var app = new Angel()..lazyParseBodies = true;
   var fs = const LocalFileSystem();
@@ -41,5 +69,4 @@ main() async {
   var server = await http.startServer('127.0.0.1', 3000);
   print('Listening at http://${server.address.address}:${server.port}');
 }
-
 ```

example/main.dart

@@ -1,6 +1,7 @@
 import 'package:angel_framework/angel_framework.dart';
 import 'package:angel_seo/angel_seo.dart';
 import 'package:angel_static/angel_static.dart';
+import 'package:dart2_constant/convert.dart';
 import 'package:file/local.dart';
 
 main() async {
@@ -8,7 +9,8 @@ main() async {
   var fs = const LocalFileSystem();
   var http = new AngelHttp(app);
 
-  var vDir = inlineAssets(
+  // You can wrap a [VirtualDirectory]
+  var vDir = inlineAssetsFromVirtualDirectory(
     new VirtualDirectory(
       app,
       fs,
@@ -18,6 +20,20 @@ main() async {
 
   app.use(vDir.handleRequest);
 
+  // OR, just add a finalizer. Note that [VirtualDirectory] *streams* its response,
+  // so a response finalizer does not touch its contents.
+  //
+  // You likely won't need to use both; it just depends on your use case.
+  app.responseFinalizers.add(inlineAssets(fs.directory('web')));
+
+  app.get('/using_response_buffer', (ResponseContext res) async {
+    var indexHtml = fs.directory('web').childFile('index.html');
+    var contents = await indexHtml.readAsString();
+    res
+      ..headers['content-type'] = 'text/html; charset=utf-8'
+      ..buffer.add(utf8.encode(contents));
+  });
+
   app.use(() => throw new AngelHttpException.notFound());
 
   var server = await http.startServer('127.0.0.1', 3000);

lib/src/inline_assets.dart

@@ -15,7 +15,81 @@ import 'package:path/path.dart' as p;
 ///
 /// In this case, "internal resources" refers to a URI *without* a scheme, i.e. `/site.css` or
 /// `foo/bar/baz.js`.
-VirtualDirectory inlineAssets(VirtualDirectory vDir) => new _InlineAssets(vDir);
+RequestMiddleware inlineAssets(Directory assetDirectory) {
+  return (req, res) {
+    if (res.willCloseItself ||
+        res.streaming ||
+        res.contentType.mimeType != 'text/html') {
+      return new Future<bool>.value(true);
+    } else {
+      var doc = html.parse(utf8.decode(res.buffer.takeBytes()));
+      return inlineAssetsIntoDocument(doc, assetDirectory).then((_) {
+        res.buffer.add(utf8.encode(doc.outerHtml));
+        return false;
+      });
+    }
+  };
+}
+
+/// Wraps a `VirtualDirectory` to patch the way it sends
+/// `.html` files.
+///
+/// In any `.html` file sent down, `link` and `script` elements that point to internal resources
+/// will have the contents of said file read, and inlined into the HTML page itself.
+///
+/// In this case, "internal resources" refers to a URI *without* a scheme, i.e. `/site.css` or
+/// `foo/bar/baz.js`.
+VirtualDirectory inlineAssetsFromVirtualDirectory(VirtualDirectory vDir) =>
+    new _InlineAssets(vDir);
+
+/// Replaces `link` and `script` tags within a [doc] with the static contents they would otherwise trigger an HTTP request to.
+///
+/// Powers both [inlineAssets] and [inlineAssetsFromVirtualDirectory].
+Future inlineAssetsIntoDocument(
+    html.Document doc, Directory assetDirectory) async {
+  var linksWithRel = doc.head
+          ?.getElementsByTagName('link')
+          ?.where((link) => link.attributes['rel'] == 'stylesheet') ??
+      <html.Element>[];
+
+  for (var link in linksWithRel) {
+    if (link.attributes.containsKey('data-no-inline')) {
+      link.attributes.remove('data-no-inline');
+    } else {
+      var uri = Uri.parse(link.attributes['href']);
+
+      if (uri.scheme.isEmpty) {
+        var styleFile = assetDirectory.childFile(uri.path);
+
+        if (await styleFile.exists()) {
+          var style = new html.Element.tag('style')
+            ..innerHtml = await styleFile.readAsString();
+          link.replaceWith(style);
+        }
+      }
+    }
+  }
+
+  var scripts = doc
+      .getElementsByTagName('script')
+      .where((script) => script.attributes.containsKey('src'));
+
+  for (var script in scripts) {
+    if (script.attributes.containsKey('data-no-inline')) {
+      script.attributes.remove('data-no-inline');
+    } else {
+      var uri = Uri.parse(script.attributes['src']);
+
+      if (uri.scheme.isEmpty) {
+        var scriptFile = assetDirectory.childFile(uri.path);
+        if (await scriptFile.exists()) {
+          script.attributes.remove('src');
+          script.innerHtml = await scriptFile.readAsString();
+        }
+      }
+    }
+  }
+}
 
 class _InlineAssets extends VirtualDirectory {
   final VirtualDirectory inner;
@@ -34,49 +108,7 @@ class _InlineAssets extends VirtualDirectory {
     if (p.extension(file.path) == '.html') {
       var contents = await file.readAsString();
       var doc = html.parse(contents, sourceUrl: file.uri.toString());
-
+      await inlineAssetsIntoDocument(doc, inner.source);
-      var linksWithRel = doc.head
-              ?.getElementsByTagName('link')
-              ?.where((link) => link.attributes['rel'] == 'stylesheet') ??
-          <html.Element>[];
-
-      for (var link in linksWithRel) {
-        if (link.attributes.containsKey('data-no-inline')) {
-          link.attributes.remove('data-no-inline');
-        } else {
-          var uri = Uri.parse(link.attributes['href']);
-
-          if (uri.scheme.isEmpty) {
-            var styleFile = inner.source.childFile(uri.path);
-
-            if (await styleFile.exists()) {
-              var style = new html.Element.tag('style')
-                ..innerHtml = await styleFile.readAsString();
-              link.replaceWith(style);
-            }
-          }
-        }
-      }
-
-      var scripts = doc
-          .getElementsByTagName('script')
-          .where((script) => script.attributes.containsKey('src'));
-
-      for (var script in scripts) {
-        if (script.attributes.containsKey('data-no-inline')) {
-          script.attributes.remove('data-no-inline');
-        } else {
-          var uri = Uri.parse(script.attributes['src']);
-
-          if (uri.scheme.isEmpty) {
-            var scriptFile = inner.source.childFile(uri.path);
-            if (await scriptFile.exists()) {
-              script.attributes.remove('src');
-              script.innerHtml = await scriptFile.readAsString();
-            }
-          }
-        }
-      }
 
       res
         ..headers['content-type'] = 'text/html; charset=utf8'