The default commenting system of WordPress uses Gravatar services to display the profile picture of the comment author.
There are three advantages of Caching Gravatar images and serving from CDN
- HTTP/2 allows parallel downloading, so it is better to reduce the unnecessary DNS lookup and TCP timing that goes in the extra domain (secure.gravatar.com).
- By default, it caches images only for 300 seconds in a browser that we can increase.
- Concerning GDPR, we can limit the collection of log information by sending the BunnyCDN IP address to the Gravatar server instead of the actual visitor’s IP. 👏
Prerequisite
- A pull zone with a custom hostname –
www.example.comfor HTML Caching. 🔥 - Or, a Pull Zone with traditional
cdn.example.comstatic content caching
To achieve this, first we need to create few edge rules then make search replace in Document.
Step 1. Set custom Request Header
- Create an Edge rule
- Action: Set Request Header
- Header name: host
- Header value: secure.gravatar.com
- Condition Matching: Match Any
- Conditions: IF Request URL: Match Any:
https://www.example.com/avatar/*
Step 2. Override origin to secure.gravatar.com
Step 3. Enforce CDN Caching
- Create another Edge rule
- Action: Override Cache Time
- Cache time in seconds: 31536000
- Condition Matching: Match Any
- Conditions: If Request URL: Match Any:
https://www.example.com/avatar/*
Step 4. Enable Browser Caching for Gravatar
- Create another Edge rule
- Action: Set Response Header
- Header name: Cache-Control
- Header Value: max-age=31536000
- Condition Matching: Match Any
- Conditions: If Request URL: Match Any:
https://www.example.com/avatar/*
Step 5. Serve Images from CDN hostname
- Take a backup before proceeding.
- Install and Activate ‘Real Time Find and Replace‘ WordPress Plugin to make on-the-fly changes in the HTML document.
- Go to Tools and menu setup this plugin.
- Find:
https://secure.gravatar.com - Replace: https://www.example.com
That’s all. Now all your Gravatar images will appear from www.example.com address.