R2 (3)

Last updated Jan 28, 2026 - R2 Reference

Buckets

Specify R2 Buckets to add to your environment as follows:

const mf = new Miniflare({
    r2Buckets: ["BUCKET1", "BUCKET2"],
});

Manipulating Outside Workers

For testing, it can be useful to put/get data from R2 storage outside a worker. You can do this with the getR2Bucket method:

import { Miniflare } from "miniflare";

const mf = new Miniflare({
    modules: true,
    script: `
  export default {
    async fetch(request, env, ctx) {
      const object = await env.BUCKET.get("count");
      const value = parseInt(await object.text()) + 1;
      await env.BUCKET.put("count", value.toString());
      return new Response(value.toString());
    }
  }
  `,
    r2Buckets: ["BUCKET"],
});

const bucket = await mf.getR2Bucket("BUCKET");
await bucket.put("count", "1");

const res = await mf.dispatchFetch("http://localhost:8787/");
console.log(await res.text()); // 2
console.log(await (await bucket.get("count")).text()); // 2

Was this helpful?

YesNo

On this page

R2 (3) - 图1Docs

{"@context":"https://schema.org","@type":"TechArticle","@id":"https://developers.cloudflare.com/workers/testing/miniflare/storage/r2/#page","headline":"R2","description":"Specify R2 Buckets to add to your environment as follows:","url":"https://developers.cloudflare.com/workers/testing/miniflare/storage/r2/","inLanguage":"en","image":"https://developers.cloudflare.com/workers/testing/miniflare/storage/r2/og.png?v=4db980a2ba80aab2","dateModified":"2026-01-28","publisher":{"@type":"Organization","name":"Cloudflare","description":"One platform for your apps, agents, and workforce. Build, secure, and scale without managing infrastructure","url":"https://www.cloudflare.com/","sameAs":["https://github.com/cloudflare","https://www.linkedin.com/company/cloudflare","https://x.com/cloudflare"],"logo":{"@type":"ImageObject","url":"https://developers.cloudflare.com/logo.svg"},"address":{"@type":"PostalAddress","streetAddress":"101 Townsend St","addressLocality":"San Francisco","addressRegion":"CA","postalCode":"94107","addressCountry":"US"},"contactPoint":[{"@type":"ContactPoint","contactType":"Customer Support","url":"https://support.cloudflare.com/","availableLanguage":["English"]},{"@type":"ContactPoint","contactType":"Sales","url":"https://www.cloudflare.com/contact/","availableLanguage":["English"]}]},"isPartOf":{"@type":"WebSite","@id":"https://developers.cloudflare.com/#website","name":"Cloudflare Docs","url":"https://developers.cloudflare.com/"}}

description: Write integration tests against Workers using Miniflare. title: Writing tests image: https://developers.cloudflare.com/workers/testing/miniflare/writing-tests/og.png?v=8cabf3051ccb3214

Skip to content

Documentation Index
Fetch the complete documentation index at: https://developers.cloudflare.com/workers/llms.txt
Use this file to discover all available pages before exploring further.