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  1. Products
  2. Workers
  3. Examples
  4. Block on TLS

Block on TLS

Inspects the incoming request's TLS version and blocks if under TLSv1.2.
export default {
  async fetch(request) {
    try {
      const tlsVersion = request.cf.tlsVersion;
      // Allow only TLS versions 1.2 and 1.3
      if (tlsVersion !== "TLSv1.2" && tlsVersion !== "TLSv1.3") {
        return new Response("Please use TLS version 1.2 or higher.", {
          status: 403,
        });
      }
      return fetch(request);
    } catch (err) {
      console.error(
        "request.cf does not exist in the previewer, only in production"
      );
      return new Response(`Error in workers script ${err.message}`, {
        status: 500,
      });
    }
  },

};

export default {
  async fetch(request: Request) {
    try {
      const tlsVersion = request.cf.tlsVersion;
      // Allow only TLS versions 1.2 and 1.3
      if (tlsVersion !== "TLSv1.2" && tlsVersion !== "TLSv1.3") {
        return new Response("Please use TLS version 1.2 or higher.", {
          status: 403,
        });
      }
      return fetch(request);
    } catch (err) {
      console.error(
        "request.cf does not exist in the previewer, only in production"
      );
      return new Response(`Error in workers script ${err.message}`, {
        status: 500,
      });
    }
  },

} satisfies ExportedHandler;