Cache Policy

速盾网络 Team

Caching policies define advanced caching schemes that can be applied across the domain name. Policies combine multiple cache settings into a reusable configuration to facilitate unified management of cache behavior.

Understand caching strategies

A cache policy is a named configuration that specifies:

What content is cached
How long is it cached?
How to handle cache keys
Compression and optimization settings

code

缓存策略 "静态资源"
├── TTL：30天
├── 浏览器TTL：1天
├── 缓存键：URL + Accept-Encoding
├── 压缩：Brotli、Gzip
└── 提供陈旧内容：启用

Default policy

Sudun provides pre-configured policies for common use cases:

Standard policy

Balanced caching scheme for a typical website:

Set item	Take the value
Edge TTL	Follow the origin header
Browser TTL	Follow the origin header
cache key	URL + query string
Compression	Automatic
Provide stale content	Only when there is an error

Aggressive strategy

Maximizing caching schemes for static content:

Set item	Take the value
Edge TTL	30 days
Browser TTL	7 days
cache key	URL only
Compression	Always enabled
Provide stale content	Always enabled

Dynamic Strategy

Minimized caching schemes for dynamic content:

Set item	Take the value
Edge TTL	None
Browser TTL	None
cache key	Not applicable
Compression	Real-time compression
Provide stale content	Never

Create custom policies

Dashboard settings

Go to Domains → and select your domain name
Navigate to Cache → policies
Click Create Policy
Configure policy settings
Click Save

Policy configuration

json

{
  "name": "我的静态策略",
  "description": "静态资源策略",
  "settings": {
    "cache": {
      "edge_ttl": 2592000,
      "browser_ttl": 86400,
      "respect_origin": false
    },
    "cache_key": {
      "include_query_string": false,
      "include_headers": ["Accept-Encoding"]
    },
    "optimization": {
      "compression": "auto",
      "minify": false
    },
    "stale": {
      "serve_while_revalidate": true,
      "serve_on_error": true,
      "max_stale_age": 86400
    }
  }
}

Policy settings

TTL settings

Control cache duration:

Set item	Description	Value range
edge_ttl	Edge node cache time	0 - 31536000 (1 year)
browser_ttl	Browser cache time	0 - 31536000
respect_origin	Follow the origin header	true/false
min_ttl	Minimum cache time	0 - 86400
max_ttl	Maximum cache time	0 - 31536000

TTL Priority Rules:

code

若 respect_origin = true：
  TTL = 源站Cache-Control值（在min/max范围内）

若 respect_origin = false：
  TTL = edge_ttl设置值

Cache key settings

Define the unique identity of the cached content:

json

{
  "cache_key": {
    "include_query_string": true,
    "query_string_whitelist": ["page", "sort"],
    "query_string_blacklist": ["utm_*", "fbclid"],
    "include_headers": ["Accept-Encoding", "Accept-Language"],
    "include_cookies": [],
    "include_device_type": false,
    "include_geo": false
  }
}

Cache key options:

options	Effect
include_query_string	Differentiate caches by query parameters
query_string_whitelist	Only these parameters affect the cache
query_string_blacklist	Ignore these parameters
include_headers	Differentiate caches by request header
include_cookies	Differentiate cache by cookie
include_device_type	Differentiate between mobile/desktop caches
include_geo	Differentiate caches by country

Compression settings

Configure content compression:

json

{
  "compression": {
    "mode": "auto",
    "algorithms": ["br", "gzip", "deflate"],
    "min_size": 1024,
    "types": ["text/*", "application/json", "application/javascript"]
  }
}

Compression mode:

mode	behavior
auto	Automatically compress according to content type and size
always	Always compress eligible content
never	Disable compression
origin	Use origin compression only

Stale content settings

Configure stale content behavior:

json

{
  "stale": {
    "serve_while_revalidate": true,
    "serve_on_error": true,
    "max_stale_age": 86400,
    "error_codes": [500, 502, 503, 504]
  }
}

Apply the policy

Apply to paths

Assign a policy to a specific path:

json

{
  "policy_assignments": [
    {
      "policy": "aggressive-static",
      "match": {
        "path": "/static/*"
      }
    },
    {
      "policy": "dynamic",
      "match": {
        "path": "/api/*"
      }
    }
  ]
}

Apply to file types

Assignment Policies by File Extension:

json

{
  "policy": "aggressive-static",
  "match": {
    "file_extensions": ["css", "js", "jpg", "png", "woff2"]
  }
}

Apply to content types

Assign policies by response content type:

json

{
  "policy": "standard",
  "match": {
    "content_type": ["text/html", "application/xhtml+xml"]
  }
}

Strategy inheritance

Policies can be inherited from other policies:

json

{
  "name": "my-images-policy",
  "inherits": "aggressive-static",
  "overrides": {
    "cache": {
      "browser_ttl": 604800
    },
    "optimization": {
      "image_optimization": true
    }
  }
}

Inheritance Chain:

code

基础策略：aggressive-static
└── my-images-policy（继承并覆盖 browser_ttl）
    └── my-hero-images（继承并覆盖图像质量）

Policy versioning

Version control

Track changes in strategy over time:

json

{
  "name": "static-assets",
  "version": 3,
  "created_at": "2024-01-01T00:00:00Z",
  "updated_at": "2024-01-15T10:30:00Z",
  "changelog": [
    {
      "version": 3,
      "date": "2024-01-15",
      "changes": "将浏览器 TTL 增加到 7 天"
    },
    {
      "version": 2,
      "date": "2024-01-10",
      "changes": "添加了 Brotli 压缩"
    }
  ]
}

Rollback

Revert to a previous policy version:

Go to Policies → to select a policy
Click on Version History
Select the version you want to restore
Click Rollback

Strategy testing

Preview mode

Test policy changes before deployment:

json

{
  "preview": true,
  "test_urls": [
    "https://example.com/test-page",
    "https://example.com/static/test.css"
  ]
}

A/B testing

Test strategy effectiveness:

json

{
  "ab_test": {
    "enabled": true,
    "variants": [
      {
        "name": "control",
        "policy": "current-policy",
        "weight": 50
      },
      {
        "name": "experiment",
        "policy": "new-policy",
        "weight": 50
      }
    ],
    "metrics": ["cache_hit_ratio", "origin_requests", "ttfb"]
  }
}

Common policy patterns

E-commerce product pages

json

{
  "name": "product-pages",
  "settings": {
    "cache": {
      "edge_ttl": 3600,
      "browser_ttl": 300
    },
    "cache_key": {
      "include_query_string": true,
      "query_string_whitelist": ["variant", "color", "size"]
    },
    "stale": {
      "serve_while_revalidate": true,
      "max_stale_age": 3600
    }
  }
}

News/Blog Posts

json

{
  "name": "blog-content",
  "settings": {
    "cache": {
      "edge_ttl": 600,
      "browser_ttl": 60
    },
    "stale": {
      "serve_while_revalidate": true,
      "serve_on_error": true
    }
  }
}

API response

json

{
  "name": "api-cacheable",
  "settings": {
    "cache": {
      "edge_ttl": 60,
      "browser_ttl": 0,
      "respect_origin": true
    },
    "cache_key": {
      "include_query_string": true,
      "include_headers": ["Authorization"]
    }
  }
}

Versioned resources

json

{
  "name": "immutable-assets",
  "settings": {
    "cache": {
      "edge_ttl": 31536000,
      "browser_ttl": 31536000,
      "immutable": true
    },
    "cache_key": {
      "include_query_string": false
    }
  }
}

Strategy analysis

View policy performance metrics:

Indicators	Description
Cache hit rate	The percentage of requests that serve from the cache
Origin uninstall rate	Origin request reduction percentage
Save bandwidth	The amount of data provided from the cache
Average TTL	The average time content spends in the cache

Dashboard metrics

Go to Analyze → cache performance
Filter by policy name
View metrics over time

Troubleshooting

The policy is not in effect

Check the policy assignment rules
Verify path/extension match
Check the policy priority order
View the origin response header

Unexpected caching behavior

Check if the origin response header overrides the policy
Verify the cache key configuration
Use curl tests to see the response header
Check for conflicting rules

Low cache hit ratio

Check the cache key settings (are they too specific?) ）
Check the TTL value (is it too short?) ）
Analyze query string variations
Consider the device/geographic triage impact

API Reference

Create a policy

bash

curl -X POST https://api.Sudun.com/v1/domains/example.com/policies \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "my-policy",
    "settings": {
      "cache": {"edge_ttl": 86400},
      "compression": {"mode": "auto"}
    }
  }'

Update the policy

bash

curl -X PUT https://api.Sudun.com/v1/domains/example.com/policies/my-policy \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "settings": {
      "cache": {"edge_ttl": 172800}
    }
  }'

List the strategy

bash

curl -X GET https://api.Sudun.com/v1/domains/example.com/policies \
  -H "Authorization: Bearer YOUR_API_KEY"

Need help with caching policies? Please contact support@Sudun.com

Cache Policy

Understand caching strategies

Default policy

Standard policy

Aggressive strategy

Dynamic Strategy

Create custom policies

Dashboard settings

Policy configuration

Policy settings

TTL settings

Cache key settings

Compression settings

Stale content settings

Apply the policy

Apply to paths

Apply to file types

Apply to content types

Strategy inheritance

Policy versioning

Version control

Rollback

Strategy testing

Preview mode

A/B testing

Common policy patterns

E-commerce product pages

News/Blog Posts

API response

Versioned resources

Strategy analysis

Dashboard metrics

Troubleshooting

The policy is not in effect

Unexpected caching behavior

Low cache hit ratio

API Reference

Create a policy

Update the policy

List the strategy

Tags

Understand caching strategies

Default policy

Standard policy

Aggressive strategy

Dynamic Strategy

Create custom policies

Dashboard settings

Policy configuration

Policy settings

TTL settings

Cache key settings

Compression settings

Stale content settings

Apply the policy

Apply to paths

Apply to file types

Apply to content types

Strategy inheritance

Policy versioning

Version control

Rollback

Strategy testing

Preview mode

A/B testing

Common policy patterns

E-commerce product pages

News/Blog Posts

API response

Versioned resources

Strategy analysis

Dashboard metrics

Troubleshooting

The policy is not in effect

Unexpected caching behavior

Low cache hit ratio

API Reference

Create a policy

Update the policy

List the strategy