This document discusses SEO challenges for single-page applications (SPAs) and solutions for making SPAs crawlable by search engines. SPAs work well for users but not search bots because bots only see empty HTML pages without rendered content. The document recommends using a headless browser to render the SPA on the server and return fully rendered HTML to search bots. This allows bots to index the site properly. Several JavaScript frameworks that support server-side rendering out of the box are also discussed, including Derby.js, Meteor.js and Atma.js. The document concludes by addressing questions about improving rendering delays and monitoring loading in SPAs.

1. SEO methods in SinglePage Applications
Or how to make your app
Google bot friendly

2. Вячеслав Потравный
Vyatcheslav Potravnyy
Front-End Team Lead at

3. http://bit.ly/seo-js

4. What is a problem?

5. How SPA works for user?
1. User opens http://blog.ru/index.html#/articles/1
2. Emtpy index.html loading with links on JS
3. User loads an App (all JavaScript code)
4. Router starting - here we know about #/articles/1
5. Models starting and downloads JSON’s
6. Views starting and renders templates
7. PROFIT! User see the content

6. How SPA works for Google bot?
1. Bot opens http://blog.ru/index.html#/articles/1
2. Emtpy index.html loading with links on JS

7. What is the solution?

8. What does Google advice?
1. Bot see URL .../index.html#!/articles/1
2. Bot knows it’s AJAX site, and does not use this URL.
It uses .../index.html?_escaped_fragment_=/articles/1
3. We handle this on server, and send rendered HTML
4. Bot associates this page with original URL
5. PROFFIT!

9. But if we have no hashbang?
1. Bot downloads page .../index.html
2. Bot sees <meta name="fragment" content="!">
3. Bot downloads .../index.html?_escaped_fragment_=
4. Server rendering

10. How to render App?

11. 1. Write all on server framework
As webapps used to be written years ago.

12. 2. Write content parts on server
framework (like Twitter)
+ Native solution
- Rewrite a lot
+ User gets content fast
- Duplicate code
- Complexity grows
- Only main content indexed
- No longer a frontend app

13. 3. Run in browser and save HTML
+ Not a lot of work
+ Architecture independed
+ Bot gets the same page
- Slow and hard for server

14. Manually?! No. Headless browser
❏ HtmlUnit
❏ crawljax
❏ watij
❏ Phantom JS

15. How does this work?
1. Bot request .../index.html?_escaped_fragment_=/page
2. We filter this request to another route
3. We run headless browser with original URL
4. Let all requests be finished
5. Get final HTML from headless browser
6. Remove <scripts> from HTML
7. Response to Google bot
8. PROFIT!

18. What can be improved?
1. Rendering delay
a. Make on CRON and save on disk
b. Cache with nginx or Varnish
2. Loading detection
a. Wait for all requests
b. Flag on body
c. App event, handled on Node.js side

19. What about future?
Full-stack
(aka Isomorphic)

20. Benefits
1. Both server & client written in one language - JS
2. You can reuse generic code on server & clients
3. Server-side rendering for SEO & performance?
4. Simply create two-way API’s

21. Derby.js

22. 1. SEO from the box
2. Huge localization abilities
3. Device adaptiveness abilities
4. Production-ready
5. Based on YUI

23. 1. Almost Backbone
2. Very light and flexible
3. SEO from the box
4. Its framework, not a plug-in library
5. Too simple for huge apps

24. Meteor.js
1. Access to data from everywhere
2. 2-way API with Latency Compensation
3. Simple dive-in
4. Biggest community
5. Own packages instead of NPM
6. SEO through phantom.js

25. Atma.js
1. SEO from the box
2. Component ideology
3. Complex solution - lot of tools
4. No community yet
5. No documentation yet

26. Derby.js
1. SEO from the box
2. User gets HTML at very start
3. 2-way API and Realtime Collaboration
4. Most “smart”
5. Built on other open-source components
6. Hard to dive-in
7. Deps Redis & MongoDB

27. Questions?
Sources:
Google Specification
Backbone Tutorials
The Digital Self
Year of Moo
Derby.js
Vyatcheslav Potravnyy
Happy New Front-end!
by Geeks Lab
(January 18, 2014)