A presentation at AtlantaPHP in in Atlanta, GA, USA by Jonathon Hill
Building for Success and Failure with AtlantaPHP, October 2014
“Let’s Build a Blog!” Says Every Developer Ever
What is it? • Discussion web service • Free as in beer • Integrates with everything • Quality content • OAuth and SSO • Embeddable widget • Web API
Fundamentals A crash course
Forum Thread Post
Category Limitations • Categories may only be created using the API. • Moderation may not be performed on posts by Category, only by Forum and Thread.
Disqus API threads/create threads/list posts/create posts/list posts/report Full documentation is available at http://disqus.com/api
Registering Your App https://disqus.com/api/applications /register/ 1. Specify Domains 2. Set Permissions Read Read and Write Read, Write, and Manage 3. Save Tokens Access Token API Key API Secret
Create a Forum https://disqus.com/admin/create/ 1. Name your site 2. Specify a unique domain Creating an application does not implicitly create a forum!
Posting to Disqus As a user Authenticate via OAuth As a guest 1. Enable “Allow guests to comment” (Settings > General) 2. Application domain must be set correctly 3. Use the magic API key: E8Uh5l5fHZ6gD8U3KycjAIAk46f68Zw7 C6eW8WSjZvCLXebZ7p0r1yrYDrLilk2F
drexarj/disqus-php github.com/disqus/disqus-php Composer: drexarj/disqus-php
What could possibly go wrong?
Caching to the Rescue
Caching to the Rescue
It’s Dynamic Data… • New posts submitted • Moderator approves post • Moderator disapproves post • User flags a post as objectionable
Conflicting Objectives • High load • • Short cache expiration Failover • No cache expiration • How to synchronize?
Adding a Failover Cache burst cache 1 2 3 failover cache
Failing Over burst cache 1 2 3 failover cache
Adding a Health Check burst cache 1 2 3 4 failover cache
Caching Health Status • If health status expires, everything just fails over • Adjust the health status expiration to back off: • FAIL 1: expiration=2 minutes • FAIL 2: expiration=4 minutes • FAIL 3: expiration=8 minutes • …etc
“Is it worth it?” –You
Implementation: Cache Servers • Burst: memcached • Failover: MongoDB (or Redis)
Implementation: Scripts • Health check • Cache warmup • Thread creation
Implementation: API Client • Guzzle-based client (compwright/disguz) • Custom Guzzle Cache adapters
Building for Success and Failure with AtlantaPHP, October 2014
Thank you! • https://github.com/compwright/disqus-demo • https://github.com/compwright/disguz • https://github.com/compwright/disqus-cli Feedback: https://joind.in/12119
Disqus provides an exceptionally effective store for user-generated content, but how do you protect against API failures or deluges of heavy traffic, while maintaining Disqus as the single source of truth? In this October 2nd, 2014 presentation, Jonathon Hill discusses a caching strategy and walk through some of the nuances of the Disqus API.
The following resources were mentioned during the presentation or are useful additional information.
Demo project for my talk, “Building for Success and Failure with Disqus”
An unofficial Disqus API client based on the Guzzle 3 PHP library.
A lightweight command line client for the Disqus API
for free. You
can too.