sieve2workers 0.1.2

Convert a Sieve program into a Cloudflare Workers for Cloudflare Email Routing.
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import { createMimeMessage } from "mimetext";
import { EmailMessage } from "cloudflare:email";
import PostalMime from "postal-mime";

async function streamToArrayBuffer(stream, streamSize) {
  let result = new Uint8Array(streamSize);
  let bytesRead = 0;
  const reader = stream.getReader();
  while (true) {
    const { done, value } = await reader.read();
    if (done) {
      break;
    }
    result.set(value, bytesRead);
    bytesRead += value.length;
  }
  return result;
}

export async function run({ message, env }) {
  const extraHeaders = new Headers();
  const raw = await streamToArrayBuffer(message.raw, message.rawSize);
  const parsedMessage = await PostalMime.parse(raw);
  console.log("parsedMessage headers", parsedMessage.headers);
  console.log("parsedMessage to", parsedMessage.to);
  console.log("parsedMessage cc", parsedMessage.cc);
  console.log("parsedMessage subject", parsedMessage.subject);
  console.log("parsedMessage messageId", parsedMessage.messageId);
  console.log("parsedMessage from", parsedMessage.from);
  const variables = {};
  async function scoreEmail() {
    const response = await env.AI.run("@cf/huggingface/distilbert-sst-2-int8", {
      text: raw,
    });
  }

  try {
    if (
      parsedMessage.headers["Fastmail-MaskedEmail"].value.includes(
        " state=disabled",
      )
    ) {
      console.log("stop");
      return;
    }
  } catch (err) {
    console.error("rule 4 failed and has been skipped", err);
  }
  try {
    if (parsedMessage.headers["X-Spam-Known-Sender"].value.match(/yes.*/)) {
      try {
        if (parsedMessage.headers["X-Backscatter"].value.includes("yes")) {
          try {
            if (parsedMessage.headers["X-LinkName"].value.match(/.*/)) {
              variables["local0"] = "Y";
              delete variables["local1"];
            }
          } catch (err) {
            console.error("rule 12 failed and has been skipped", err);
          }
        }
      } catch (err) {
        console.error("rule 12 failed and has been skipped", err);
      }
    }
  } catch (err) {
    console.error("rule 12 failed and has been skipped", err);
  }
  try {
    if ("" === "Y") {
      console.log("stop");
      return;
    }
  } catch (err) {
    console.error("rule 15 failed and has been skipped", err);
  }
  try {
    if (raw.includes("MAKE MONEY FAST")) {
      console.log("discard"); // discard the email
      return;
    }
  } catch (err) {
    console.error("rule 18 failed and has been skipped", err);
  }
  try {
    if (raw.includes("to be saved")) {
      await env.BINDING_NAME.put("foobar", raw);
    }
  } catch (err) {
    console.error("rule 21 failed and has been skipped", err);
  }
  try {
    if ((await scoreEmail()) == 37) {
      console.log("discard"); // discard the email
      return;
    }
  } catch (err) {
    console.error("rule 24 failed and has been skipped", err);
  }
}