Add access to AST and element model data to the status pages

pkg/analysis_server/lib/src/status/pages.dart

 // Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
 
 import 'package:intl/intl.dart';
 
 /// Contains a collection of Pages.
 abstract class Site {
   final String title;
   List<Page> pages = [];
+  List<Page> secondaryPages = [];
 
   Site(this.title);
 
   String get customCss => '';
 
-  void handleGetRequest(HttpRequest request) {
+  Future<Null> handleGetRequest(HttpRequest request) async {
     try {
       String path = request.uri.path;
 
       if (path == '/') {
         respondRedirect(request, pages.first.path);
         return;
       }
 
       for (Page page in pages) {
         if (page.path == path) {
           HttpResponse response = request.response;
           response.headers.contentType = ContentType.HTML;
-          response.write(page.generate(request.uri.queryParameters));
+          response.write(await page.generate(request.uri.queryParameters));
           response.close();
           return;
         }
       }
 
-      respond(request, createUnknownPage(path), HttpStatus.NOT_FOUND);
+      for (Page page in secondaryPages) {
+        if (page.path == path) {
+          HttpResponse response = request.response;
+          response.headers.contentType = ContentType.HTML;
+          response.write(await page.generate(request.uri.queryParameters));
+          response.close();
+          return;
+        }
+      }
+
+      await respond(request, createUnknownPage(path), HttpStatus.NOT_FOUND);
     } catch (e, st) {
       try {
-        respond(request, createExceptionPage('$e', st),
+        await respond(request, createExceptionPage('$e', st),
             HttpStatus.INTERNAL_SERVER_ERROR);
       } catch (e, st) {
         HttpResponse response = request.response;
         response.statusCode = HttpStatus.INTERNAL_SERVER_ERROR;
         response.headers.contentType = ContentType.TEXT;
         response.write('$e\n\n$st');
         response.close();
       }
     }
   }
 
   Page createUnknownPage(String unknownPath);
 
   Page createExceptionPage(String message, StackTrace trace);
 
-  void respond(HttpRequest request, Page page, [int code = HttpStatus.OK]) {
+  Future<Null> respond(HttpRequest request, Page page,
+      [int code = HttpStatus.OK]) async {
     HttpResponse response = request.response;
     response.statusCode = code;
     response.headers.contentType = ContentType.HTML;
-    response.write(page.generate(request.uri.queryParameters));
+    response.write(await page.generate(request.uri.queryParameters));
     response.close();
   }
 
   void respondRedirect(HttpRequest request, String pathFragment) {
     HttpResponse response = request.response;
     response.statusCode = HttpStatus.MOVED_TEMPORARILY;
     response.redirect(request.uri.resolve(pathFragment));
   }
 }
 
 /// An entity that knows how to serve itself over http.
 abstract class Page {
   final StringBuffer buf = new StringBuffer();
 
   final String id;
   final String title;
   final String description;
 
   Page(this.id, this.title, {this.description});
 
   String get path => '/$id';
 
-  String generate(Map<String, String> params) {
+  Future<String> generate(Map<String, String> params) async {
     buf.clear();
-    generatePage(params);
+    await generatePage(params);
     return buf.toString();
   }
 
   void generatePage(Map<String, String> params);
 
   void h1(String text, {String classes}) {
     if (classes != null) {
       buf.writeln('<h1 class="$classes">${escape(text)}</h1>');
     } else {
       buf.writeln('<h1>${escape(text)}</h1>');
@@ skipping 25 matching lines @@
   void inputList<T>(Iterable<T> items, void gen(T item)) {
     buf.writeln('<select size="8" style="width: 100%">');
     for (T item in items) {
       buf.write('<option>');
       gen(item);
       buf.write('</option>');
     }
     buf.writeln('</select>');
   }
 
+  Future<Null> asyncDiv(void gen(), {String classes}) async {
+    if (classes != null) {
+      buf.writeln('<div class="$classes">');
+    } else {
+      buf.writeln('<div>');
+    }
+    await gen();
+    buf.writeln('</div>');
+  }
+
   void div(void gen(), {String classes}) {
     if (classes != null) {
       buf.writeln('<div class="$classes">');
     } else {
       buf.writeln('<div>');
     }
     gen();
     buf.writeln('</div>');
   }
 
@@ skipping 26 matching lines @@
 
 String escape(String text) => text == null ? '' : HTML_ESCAPE.convert(text);
 
 final NumberFormat numberFormat = new NumberFormat.decimalPattern();
 
 String printInteger(int value) => numberFormat.format(value);
 
 String printMilliseconds(num value) => '${numberFormat.format(value)} ms';
 
 String printPercentage(num value) => '${(value * 100).toStringAsFixed(1)}%';