Cache Purge

Sudun TeamMay 3, 2026 at 11:04Estimated reading time 3 min

When to clear the cache

Common scenarios where cache needs to be cleared:

Scenario	Purge Type	Example
Content updates	Single URL	Update blog posts
Website redesign	Clear all caches	Deploy the new CSS/JS
Emergency fix	URL or tag	Security patches
Resource version changes	Clear prefixes	/assets/v2/*

Clearing method

Press URL Clear

To remove a specific URL from the cache:

code

https://example.com/blog/post-1
https://example.com/images/hero.jpg
https://example.com/css/styles.css

Best for: Individual content updates, targeted cache clearing

Press the prefix to clear

Remove all URLs that match a specific path prefix:

code

https://example.com/blog/*
https://example.com/images/*
https://example.com/api/v1/*

**Best for: Section updates, versioned resource deployment

Press the cache label to clear

Remove content associated with tags:

code

Tags: product-123, category-electronics, homepage

Best for: Dynamic content relationships, CMS integration

Clear everything

Remove all cached domain contents:

code

Domain: example.com
Action: Purge All

Warning: Clearing everything can cause a spike in origin server requests. Use with caution, preferably during periods of low traffic.

Use the Control Panel

Clear individual URLs

Go to the domain name list → and select your domain name
Go to Cache → to clear the cache**
Select Clear by URL
Enter the full URL that you want to purge
Click Clear

Press the prefix to clear

Go to Cache → to clear the cache**
Select Clear by prefix
Enter a URL prefix (for example,https://example.com/blog/
Click Clear

Clear all caches

Go to Cache → to clear the cache**
Select Clear all cache
Enter your domain name to confirm
Click Clear all

Cache tags allow content-based purge without knowing the exact URL.

Set cache labels

Add tags via the origin response header:

http

Cache-Tag: product-123, category-shoes, homepage

Or configure in Sudun:

json

{
  "cache_tags": {
    "rules": [
      {
        "match": { "path": "/products/*" },
        "tags": ["products", "catalog"]
      },
      {
        "match": { "path": "/blog/*" },
        "tags": ["blog", "content"]
      }
    ]
  }
}

Clear cache by label

bash

# Purge all content with tag "product-123"
curl -X POST https://api.Sudun.com/v1/domains/example.com/purge \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"tags": ["product-123"]}'

Labeling best practices

Tag Type	Example	Use Case
Entity ID	`product-123`	Purge when product updates
Category	`category-electronics`	Purge category pages
Content type	`blog-posts`	Purge all blog content
Template	`template-homepage`	Purge after template change

cache clearing instructions

After initiating a purge:

code

Purge Request → Sudun API → Global PoPs
                                  │
                          ┌───────┴───────┐
                          │               │
                     ~1-5 seconds    ~30 seconds
                     (most PoPs)     (all PoPs)

Purge Type	Typical Propagation
Single URL	1-5 seconds
Prefix	5-15 seconds
Cache Tag	5-15 seconds
Everything	15-60 seconds

Soft Cleaning vs Hard Cleanup

Hard Cleanup (default)

Remove content from cache immediately:

code

Cache State: MISS
Origin Request: Required

Soft clean

Mark content as outdated, but remain available:

code

Cache State: STALE
Origin Request: Background revalidation

Advantages of soft purge:

P Prevents source overload
Users see the content immediately (expired)
Provide the latest content after revalidation

bash

# 通过 API 进行软清除
curl -X POST https://api.Sudun.com/v1/domains/example.com/purge \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{"urls": ["https://example.com/page"], "soft": true}'

Clear automation

Webhooks

Trigger a purge from your CMS or deployment pipeline:

bash

# WordPress example: purge on post update
curl -X POST https://api.Sudun.com/v1/domains/example.com/purge \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{"tags": ["post-${POST_ID}"]}'

CI/CD integration

Clear cache after deployment:

yaml

# GitHub Actions example
- name: Purge CDN Cache
  run: |
    curl -X POST https://api.Sudun.com/v1/domains/$DOMAIN/purge \
      -H "Authorization: Bearer $YESudunPI_KEY" \
      -d '{"prefix": "https://$DOMAIN/assets/"}'

Need help with cache purging? Contact admin@jindundun.com