Cache Tags using Workers
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Cache Tags using Workers

Send Additional Cache Tags using Workers

Last updated Jul 6, 2026 If you want to get started quickly, click on the button below.

This creates a repository in your GitHub account and deploys the application to Cloudflare Workers.

export default {
    async fetch(request) {
        const requestUrl = new URL(request.url);
        const params = requestUrl.searchParams;
        const tags =
            params && params.has("tags") ? params.get("tags").split(",") : [];
        const url = params && params.has("uri") ? params.get("uri") : "";
        if (!url) {
            const errorObject = {
                error: "URL cannot be empty",
            };
            return new Response(JSON.stringify(errorObject), { status: 400 });
        }
        const init = {
            cf: {
                cacheTags: tags,
            },
        };
        return fetch(url, init)
            .then((result) => {
                const cacheStatus = result.headers.get("cf-cache-status");
                const lastModified = result.headers.get("last-modified");
                const response = {
                    cache: cacheStatus,
                    lastModified: lastModified,
                };
                return new Response(JSON.stringify(response), {
                    status: result.status,
                });
            })
            .catch((err) => {
                const errorObject = {
                    error: err.message,
                };
                return new Response(JSON.stringify(errorObject), { status: 500 });
            });
    },
};

export default {
    async fetch(request): Promise<Response> {
        const requestUrl = new URL(request.url);
        const params = requestUrl.searchParams;
        const tags =
            params && params.has("tags") ? params.get("tags").split(",") : [];
        const url = params && params.has("uri") ? params.get("uri") : "";
        if (!url) {
            const errorObject = {
                error: "URL cannot be empty",
            };
            return new Response(JSON.stringify(errorObject), { status: 400 });
        }
        const init = {
            cf: {
                cacheTags: tags,
            },
        };
        return fetch(url, init)
            .then((result) => {
                const cacheStatus = result.headers.get("cf-cache-status");
                const lastModified = result.headers.get("last-modified");
                const response = {
                    cache: cacheStatus,
                    lastModified: lastModified,
                };
                return new Response(JSON.stringify(response), {
                    status: result.status,
                });
            })
            .catch((err) => {
                const errorObject = {
                    error: err.message,
                };
                return new Response(JSON.stringify(errorObject), { status: 500 });
            });
    },
} satisfies ExportedHandler;

import { Hono } from "hono";

const app = new Hono();

app.all("*", async (c) => {
    const tags = c.req.query("tags") ? c.req.query("tags").split(",") : [];
    const uri = c.req.query("uri") ? c.req.query("uri") : "";

    if (!uri) {
        return c.json({ error: "URL cannot be empty" }, 400);
    }

    const init = {
        cf: {
            cacheTags: tags,
        },
    };

    const result = await fetch(uri, init);
    const cacheStatus = result.headers.get("cf-cache-status");
    const lastModified = result.headers.get("last-modified");

    const response = {
        cache: cacheStatus,
        lastModified: lastModified,
    };

    return c.json(response, result.status);
});

app.onError((err, c) => {
    return c.json({ error: err.message }, 500);
});

export default app;

from workers import WorkerEntrypoint, Response, fetch
from js import URL

class Default(WorkerEntrypoint):
    async def fetch(self, request):
        request_url = URL.new(request.url)
        params = request_url.searchParams
        tags = params["tags"].split(",") if "tags" in params else []
        url = params["uri"] or None

        if url is None:
            return Response.json({"error": "URL cannot be empty"}, status=400)

        result = await fetch(url, cf={"cacheTags": tags})

        cache_status = result.headers["cf-cache-status"]
        last_modified = result.headers["last-modified"]

        return Response.json({"cache": cache_status, "lastModified": last_modified}, status=result.status)

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description: Determine how to cache a resource by setting TTLs, custom cache keys, and cache headers in a fetch request. title: Cache using fetch image: https://developers.cloudflare.com/workers/examples/cache-using-fetch/og.png?v=7d6169fe1dc8b2ed

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Cache Tags using Workers

Cache Tags using Workers

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