Cloudflare ¶

Cloudflare is a content delivery network (CDN) that may be configured to cache HTTP responses.

While HTTP caching is disabled by default on Cloudflare, you might activate this feature via page rules. It is possible to enable caching per page, but the matching configuration is only possible via URL matching, which doesn't allow you to disable the cache when Blackfire HTTP header is present in the request.

The recommended solution is to use Cloudflare workersinstead of page rules. This solution is free of charge until 100k requests going through the workers per day. Beyond that limit, Cloudflare charges depending on the number of requests.

You can create a worker from your Cloudflare dashboard.

Worker Code ¶

Once your worker is created, you will need to add the following JavaScript code in the online editor:

addEventListener('fetch', event => {
    event.respondWith(handleRequest(event.request))
})

async function handleRequest(request) {
    const acl = [
        // Blackfire.io IPs
        // Ref https://docs.blackfire.io/reference-guide/faq#how-should-i-configure-my-firewall-to-let-blackfire-access-my-apps
        '46.51.168.2', '54.75.240.245'
        // Add your own IPs here, from which you'd like to disable the cache.
        // 'x.y.z.w'
    ]
    if (request.headers.get('x-blackfire-query') !== null && acl.includes(request.headers.get('cf-connecting-ip'))) {
        return fetch(request)
    }

    // Here, you may apply your own caching rule, the same you would have applied with page rules.
    return fetch(request, { cf: { cacheEverything: true } })
}

Then click on the Save and Deploy button.

Worker Activation ¶

Now, activate your worker from your Cloudflare domain dashboard:

Go to the Workers section and click on Add route;
Define your route (you will probably want to add everything, e.g. yourdomain.tld/*);
Choose your worker and click on Save.

Please check that the cache everything setting is disabled from your page rules, as the rules are applied after the workers. They would hence override your workers' configuration.