Cloudflare 通过 Workers 访问 R2 中存储的文件

代码在 tianheg/cloudflare/r2 。文档 R2 get started guide 。

wrangler.toml ：

    name = "r2"
    main = "src/index.js"
    compatibility_date = "2022-08-18"

    account_id = "PLACE YOUR ACCOUNT ID" # at workers page
    workers_dev = true

    [[r2_buckets]]
    binding = 'MY_BUCKET' # <~ valid JavaScript variable name
    bucket_name = 'cloudflare'

index.js ：

    const ALLOW_LIST = ['surplus-value-051.mp3'];

    // Check requests for a pre-shared secret
    const hasValidHeader = (request, env) => {
      return request.headers.get('X-Custom-Auth-Key') === env.AUTH_KEY_SECRET;
    };

    function authorizeRequest(request, env, key) {
      switch (request.method) {
        case 'PUT':
        case 'DELETE':
          return hasValidHeader(request, env);
        case 'GET':
          return ALLOW_LIST.includes(key);
        default:
          return false;
      }
    }

    export default {
      async fetch(request, env) {
        const url = new URL(request.url);
        const key = url.pathname.slice(1);

        if (!authorizeRequest(request, env, key)) {
          return new Response('Forbidden', { status: 403 });
        }

        switch (request.method) {
          case 'PUT':
            await env.MY_BUCKET.put(key, request.body);
            return new Response(`Put ${key} successfully!`);
          case 'GET':
            const object = await env.MY_BUCKET.get(key);

            if (object === null) {
              return new Response('Object Not Found', { status: 404 });
            }

            const headers = new Headers();
            object.writeHttpMetadata(headers);
            headers.set('etag', object.httpEtag);

            return new Response(object.body, {
              headers,
            });
          case 'DELETE':
            await env.MY_BUCKET.delete(key);
            return new Response('Deleted!');

          default:
            return new Response('Method Not Allowed', {
              status: 405,
              headers: {
                Allow: 'PUT, GET, DELETE',
              },
            });
        }
      },
    };