feat(aio): include more API results in search

By adding a more relaxed search on the title
of docs, we are more likely to catch API docs.

The additional search terms match anything
with a word in the title that starts with the
characters of the first term in the search.

E.g. if the search is "ngCont guide" then
search for "ngCont guide titleWords:ngCont*"

aio/e2e/app.e2e-spec.ts

@@ -92,4 +92,10 @@ describe('site App', function() {
     // Todo: add test to confirm tracking URL when navigate.
   });
 
+  describe('search', () => {
+    it('should find pages when searching by a partial word in the title', () => {
+      page.enterSearch('ngCont');
+      expect(page.getSearchResults().map(link => link.getText())).toContain('NgControl');
+    });
+  });
 });

aio/e2e/app.po.ts

@@ -1,4 +1,4 @@
-import { browser, element, by, promise, ElementFinder } from 'protractor';
+import { browser, element, by, promise, ElementFinder, ExpectedConditions } from 'protractor';
 
 const githubRegex = /https:\/\/github.com\/angular\/angular\//;
 
@@ -50,6 +50,16 @@ export class SitePage {
     return browser.executeScript('window.scrollTo(0, document.body.scrollHeight)');
   }
 
+  enterSearch(query: string) {
+    element(by.css('.search-container input[type=search]')).sendKeys(query);
+  }
+
+  getSearchResults() {
+    const results = element.all(by.css('.search-results li'));
+    browser.wait(ExpectedConditions.presenceOf(results.first()), 8000);
+    return results;
+  }
+
   /**
    * Replace the ambient Google Analytics tracker with homebrew spy
    * don't send commands to GA during e2e testing!

aio/src/app/search/search-worker.js

@@ -9,7 +9,18 @@ var SEARCH_TERMS_URL = '/generated/docs/app/search-data.json';
 importScripts('/assets/js/lunr.min.js');
 
 var index;
-var pages = {};
+var pages /* : SearchInfo */ = {};
+
+// interface SearchInfo {
+//  [key: string]: PageInfo;
+// }
+
+// interface PageInfo {
+//   path: string;
+//   type: string,
+//   titleWords: string;
+//   keyWords: string;
+// }
 
 self.onmessage = handleMessage;
 
@@ -49,15 +60,7 @@ function handleMessage(message) {
 // Use XHR to make a request to the server
 function makeRequest(url, callback) {
 
-  // The JSON file that is loaded should be an array of SearchTerms:
-  //
-  // export interface SearchTerms {
-  //   path: string;
-  //   type: string,
-  //   titleWords: string;
-  //   keyWords: string;
-  // }
-
+  // The JSON file that is loaded should be an array of PageInfo:
   var searchDataRequest = new XMLHttpRequest();
   searchDataRequest.onload = function() {
     callback(JSON.parse(this.responseText));
@@ -68,11 +71,11 @@ function makeRequest(url, callback) {
 
 
 // Create the search index from the searchInfo which contains the information about each page to be indexed
-function loadIndex(searchInfo) {
+function loadIndex(searchInfo /*: SearchInfo */) {
   return function(index) {
     // Store the pages data to be used in mapping query results back to pages
     // Add search terms from each page to the search index
-    searchInfo.forEach(function(page) {
+    searchInfo.forEach(function(page /*: PageInfo */) {
       index.add(page);
       pages[page.path] = page;
     });
@@ -81,7 +84,19 @@ function loadIndex(searchInfo) {
 
 // Query the index and return the processed results
 function queryIndex(query) {
-  var results = index.search(query);
-  // Only return the array of paths to pages
-  return results.map(function(hit) { return pages[hit.ref]; });
+  try {
+    if (query.length) {
+      // Add a relaxed search in the title for the first word in the query
+      // E.g. if the search is "ngCont guide" then we search for "ngCont guide titleWords:ngCont*"
+      var titleQuery = 'titleWords:' + query.split(' ', 1)[0] + '*';
+      var results = index.search(query + ' ' + titleQuery);
+      // Map the hits into info about each page to be returned as results
+      return results.map(function(hit) { return pages[hit.ref]; });
+    }
+  } catch(e) {
+    // If the search query cannot be parsed the index throws an error
+    // Log it and recover
+    console.log(e);
+  }
+  return [];
 }