Expose an R2 bucket to the Internet via a Worker

Below is an example Worker that exposes an R2 bucket to the Internet and demonstrates its functionality for storing and retrieving objects.

For a simpler guide level explanation of how to use R2 in a worker, refer to use R2 in a Worker.

interface Env {
  MY_BUCKET: R2Bucket
}

function objectNotFound(objectName: string): Response {
  return new Response(`<html><body>R2 object "<b>${objectName}</b>" not found</body></html>`, {
    status: 404,
    headers: {
      'content-type': 'text/html; charset=UTF-8'
    }
  })
}

export default {
  async fetch(request, env): Promise<Response> {
    const url = new URL(request.url)
    const objectName = url.pathname.slice(1)

    console.log(`${request.method} object ${objectName}: ${request.url}`)

    if (request.method === 'GET' || request.method === 'HEAD') {
      if (objectName === '') {
        if (request.method == 'HEAD') {
          return new Response(undefined, { status: 400 })
        }

        const options: R2ListOptions = {
          prefix: url.searchParams.get('prefix') ?? undefined,
          delimiter: url.searchParams.get('delimiter') ?? undefined,
          cursor: url.searchParams.get('cursor') ?? undefined,
          include: ['customMetadata', 'httpMetadata'],
        }
        console.log(JSON.stringify(options))

        const listing = await env.MY_BUCKET.list(options)
        return new Response(JSON.stringify(listing), {headers: {
          'content-type': 'application/json; charset=UTF-8',
        }})
      }

      if (request.method === 'GET') {
        const object = await env.MY_BUCKET.get(objectName, {
          range: request.headers,
          onlyIf: request.headers,
        })

        if (object === null) {
          return objectNotFound(objectName)
        }

        const headers = new Headers()
        object.writeHttpMetadata(headers)
        headers.set('etag', object.httpEtag)
        if (object.range) {
          headers.set("content-range", `bytes ${object.range.offset}-${object.range.end ?? object.size - 1}/${object.size}`)
        }
        const status = object.body ? (request.headers.get("range") !== null ? 206 : 200) : 304
        return new Response(object.body, {
          headers,
          status
        })
      }

      const object = await env.MY_BUCKET.head(objectName)

      if (object === null) {
        return objectNotFound(objectName)
      }

      const headers = new Headers()
      object.writeHttpMetadata(headers)
      headers.set('etag', object.httpEtag)
      return new Response(null, {
        headers,
      })
    }
    if (request.method === 'PUT' || request.method == 'POST') {
      const object = await env.MY_BUCKET.put(objectName, request.body, {
        httpMetadata: request.headers,
      })
      return new Response(null, {
        headers: {
          'etag': object.httpEtag,
        }
      })
    }
    if (request.method === 'DELETE') {
      await env.MY_BUCKET.delete(url.pathname.slice(1))
      return new Response()
    }

    return new Response(`Unsupported method`, {
      status: 400
    })
  }
} satisfies ExportedHandler<Env>;

Cloudflare Dashboard Discord Community Learning Center Support Portal

Cookie Settings