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TypeError: Value of "this" must be of type SubtleCrypto

See original GitHub issue

When I run this simple code, it throws an error when running from miniflare. The same code works fine running from Cloudflare (or wrangler dev without the --local flag).


export default {
  async fetch(request, env, ctx) {
    const secret = new TextEncoder().encode('test')
    const key = await crypto.subtle.importKey('raw', secret, { name: 'HMAC', hash: { name: 'SHA-512' } }, false, [

    return new Response(JSON.stringify(key), { status: 200 })


TypeError: Value of "this" must be of type SubtleCrypto
    at new NodeError (node:internal/errors:377:5)
    at Proxy.importKey (node:internal/crypto/webcrypto:517:30)
    at Object.fetch (/private/Users/leonardo/worker-test/src/index.ts:4:37)
    at /Users/leonardo/worker-test/node_modules/@miniflare/core/src/standards/event.ts:331:19
    at /Users/leonardo/worker-test/node_modules/@miniflare/shared/src/event.ts:29:9
    at ServiceWorkerGlobalScope.<anonymous> (/Users/leonardo/worker-test/node_modules/@miniflare/shared/src/event.ts:77:9)
    at ServiceWorkerGlobalScope.[nodejs.internal.kHybridDispatch] (node:internal/event_target:639:20)
    at ServiceWorkerGlobalScope.dispatchEvent (node:internal/event_target:581:26)
    at ServiceWorkerGlobalScope.dispatchEvent (/Users/leonardo/worker-test/node_modules/@miniflare/shared/src/event.ts:63:18)
    at ServiceWorkerGlobalScope.dispatchEvent (/Users/leonardo/worker-test/node_modules/@miniflare/shared/src/event.ts:87:26)

Issue Analytics

  • State:closed
  • Created a year ago
  • Reactions:4
  • Comments:7 (2 by maintainers)

github_iconTop GitHub Comments

mrbbotcommented, May 27, 2022

Hey! I’ve just released version 2.5.0 with this fix. Please let me know if you have any other issues.

brandonpittmancommented, Jun 2, 2022

Even on 2.5.0, this error is still occurring for me.

Read more comments on GitHub >

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