请求创建VCL规则：仅缓存/order/{x}/{y}层级的URL页面

Hey there, let's get this Varnish caching rule sorted for you. You need to cache URLs that exactly follow the /order/{x}/{y} format (where x and y can include alphanumeric characters and special symbols), while leaving /order/{x} and any deeper nested paths (like /order/{x}/{y}/{z}) un-cached. Here's a solid implementation for your VCL:

sub vcl_recv {
    # Cache only URLs matching the exact /order/{x}/{y} pattern
    if (req.url ~ "^/order/[^/]+/[^/]+$") {
        # Mark this request as cacheable
        set req.http.X-Cacheable = "yes";
        # Set a custom TTL (adjust this to your needs, e.g., 30m for 30 minutes)
        set req.ttl = 1h;
    } else {
        # Bypass cache for all other /order-related paths
        if (req.url ~ "^/order/") {
            return (pass);
        }
    }
}

# Optional: Configure backend response caching behavior
sub vcl_backend_response {
    if (bereq.http.X-Cacheable == "yes") {
        # Set the TTL for cached responses
        set beresp.ttl = 1h;
        # Remove cookies to avoid per-user cache variations (only do this if cookies aren't needed for these pages)
        unset beresp.http.Set-Cookie;
    }
}

Breakdown of the Rule: #

• The regex ^/order/[^/]+/[^/]+$ is critical here:

  • ^/order/ anchors the match to the start of the URL, targeting only /order paths
  • [^/]+ matches any sequence of characters except a slash—this captures your x and y values, including special characters like _, -, %, etc.
  • The trailing $ ensures the URL ends right after the second segment, which blocks deeper paths like /order/x/y/z from being cached.

• For any /order path that doesn't match the exact two-segment pattern (like /order/x or /order/x/y/z), we use return (pass) to skip caching entirely—these requests will go straight to your backend every time.

Key Notes: #

• Test the regex: Make sure it works with your actual URL patterns. You can test locally by sending sample requests to Varnish and checking cache hits/misses, or use Varnish's built-in debugging tools.
• Adjust TTL: The 1h (1 hour) TTL in the example is just a starting point—tweak this to match how often your /order/{x}/{y} content changes.
• Cookies: If your /order/{x}/{y} pages require cookies (e.g., for user-specific data), remove the unset beresp.http.Set-Cookie line. Keep in mind that cookies will make Varnish cache unique copies for each user, which might reduce cache efficiency.

内容的提问来源于stack exchange，提问作者Aj K