4 files changed, 391 insertions, 0 deletions
diff --git a/deno/mail-relay/aws/app.ts b/deno/mail-relay/aws/app.ts
new file mode 100644
index 0000000..1fda64e
--- /dev/null
+++ b/deno/mail-relay/aws/app.ts
@@ -0,0 +1,136 @@
+import { parseArgs } from "@std/cli";
+import { z } from "zod";
+import { zValidator } from "@hono/zod-validator";
+
+import log from "../log.ts";
+import config from "../config.ts";
+import { AppBase } from "../app.ts";
+import { AwsContext } from "./context.ts";
+import {
+  AwsMailDeliverer,
+  AwsMailMessageIdRewriteHook,
+  AwsMailMessageIdSaveHook,
+} from "./deliver.ts";
+import { AwsMailRetriever } from "./retriever.ts";
+
+export class AwsRelayApp extends AppBase {
+  readonly #aws = new AwsContext();
+  readonly #retriever;
+  protected readonly outboundDeliverer = new AwsMailDeliverer(this.#aws);
+
+  constructor() {
+    super();
+    this.#retriever = new AwsMailRetriever(this.#aws, this.inboundDeliverer);
+
+    this.outboundDeliverer.preHooks.push(
+      new AwsMailMessageIdRewriteHook(this.db),
+    );
+    this.outboundDeliverer.postHooks.push(
+      new AwsMailMessageIdSaveHook(this.db),
+    );
+
+    this.hono.post(
+      `/${config.get("awsInboundPath")}`,
+      async (ctx, next) => {
+        const auth = ctx.req.header("Authorization");
+        if (auth !== config.get("awsInboundKey")) {
+          return ctx.json({ "msg": "Bad auth!" }, 403);
+        }
+        await next();
+      },
+      zValidator(
+        "json",
+        z.object({
+          key: z.string(),
+          recipients: z.optional(z.array(z.string())),
+        }),
+      ),
+      async (ctx) => {
+        const { key, recipients } = ctx.req.valid("json");
+        await this.#retriever.deliverS3Mail(key, recipients);
+        return ctx.json({ "msg": "Done!" });
+      },
+    );
+  }
+
+  realServe() {
+    this.createCron({
+      name: "live-mail-recycler",
+      interval: 6 * 3600 * 1000,
+      callback: () => {
+        return this.#retriever.recycleLiveMails();
+      },
+      startNow: true,
+    });
+
+    return this.serve();
+  }
+
+  readonly cli = {
+    "init": (_: unknown) => {
+      log.info("Just init!");
+      return Promise.resolve();
+    },
+    "list-lives": async (_: unknown) => {
+      const liveMails = await this.#retriever.listLiveMails();
+      log.info(`Total ${liveMails.length}:`);
+      log.info(liveMails.join("\n"));
+    },
+    "recycle-lives": async (_: unknown) => {
+      await this.#retriever.recycleLiveMails();
+    },
+    "serve": async (_: unknown) => {
+      await this.serve().http.finished;
+    },
+    "real-serve": async (_: unknown) => {
+      await this.realServe().http.finished;
+    },
+  } as const;
+}
+
+const nonServerCli = {
+  "sendmail": async (_: unknown) => {
+    const decoder = new TextDecoder();
+    let text = "";
+    for await (const chunk of Deno.stdin.readable) {
+      text += decoder.decode(chunk);
+    }
+
+    const res = await fetch(
+      `http://localhost:${config.HTTP_PORT}/send/raw`,
+      {
+        method: "post",
+        body: text,
+      },
+    );
+    log.infoOrError(!res.ok, res);
+    log.infoOrError(!res.ok, "Body\n" + await res.text());
+    if (!res.ok) Deno.exit(-1);
+  },
+} as const;
+
+if (import.meta.main) {
+  const args = parseArgs(Deno.args);
+
+  if (args._.length === 0) {
+    throw new Error("You must specify a command.");
+  }
+
+  const command = args._[0];
+
+  if (command in nonServerCli) {
+    log.info(`Run non-server command ${command}.`);
+    await nonServerCli[command as keyof typeof nonServerCli](args);
+    Deno.exit(0);
+  }
+
+  const app = new AwsRelayApp();
+  await app.setup();
+  if (command in app.cli) {
+    log.info(`Run command ${command}.`);
+    await app.cli[command as keyof AwsRelayApp["cli"]](args);
+    Deno.exit(0);
+  } else {
+    throw new Error(command + " is not a valid command.");
+  }
+}
diff --git a/deno/mail-relay/aws/context.ts b/deno/mail-relay/aws/context.ts
new file mode 100644
index 0000000..b1e0336
--- /dev/null
+++ b/deno/mail-relay/aws/context.ts
@@ -0,0 +1,41 @@
+import {
+  CopyObjectCommand,
+  DeleteObjectCommand,
+  S3Client,
+} from "@aws-sdk/client-s3";
+import { FetchHttpHandler } from "@smithy/fetch-http-handler";
+
+import config from "../config.ts";
+
+export class AwsContext {
+  readonly credentials = () =>
+    Promise.resolve({
+      accessKeyId: config.get("awsUser"),
+      secretAccessKey: config.get("awsPassword"),
+    });
+  readonly requestHandler = new FetchHttpHandler();
+
+  get region() {
+    return config.get("awsRegion");
+  }
+}
+
+export async function s3MoveObject(
+  client: S3Client,
+  bucket: string,
+  path: string,
+  newPath: string,
+): Promise<void> {
+  const copyCommand = new CopyObjectCommand({
+    Bucket: bucket,
+    Key: newPath,
+    CopySource: `${bucket}/${path}`,
+  });
+  await client.send(copyCommand);
+
+  const deleteCommand = new DeleteObjectCommand({
+    Bucket: bucket,
+    Key: path,
+  });
+  await client.send(deleteCommand);
+}
diff --git a/deno/mail-relay/aws/deliver.ts b/deno/mail-relay/aws/deliver.ts
new file mode 100644
index 0000000..0db5fa8
--- /dev/null
+++ b/deno/mail-relay/aws/deliver.ts
@@ -0,0 +1,114 @@
+// spellchecker: words sesv2 amazonses
+
+import { SendEmailCommand, SESv2Client } from "@aws-sdk/client-sesv2";
+
+import log from "../log.ts";
+import { DbService } from "../db.ts";
+import {
+  Mail,
+  MailDeliverContext,
+  MailDeliverHook,
+  SyncMailDeliverer,
+} from "../mail.ts";
+import { AwsContext } from "./context.ts";
+
+declare module "../mail.ts" {
+  interface MailDeliverResult {
+    awsMessageId?: string;
+  }
+}
+
+export class AwsMailMessageIdRewriteHook implements MailDeliverHook {
+  readonly #db;
+
+  constructor(db: DbService) {
+    this.#db = db;
+  }
+
+  async callback(context: MailDeliverContext): Promise<void> {
+    log.info("Rewrite message ids...");
+    const addresses = context.mail.simpleFindAllAddresses();
+    log.info(`Addresses found in mail: ${addresses.join(", ")}.`);
+    for (const address of addresses) {
+      const awsMessageId = await this.#db.messageIdToAws(address);
+      if (awsMessageId != null && awsMessageId.length !== 0) {
+        log.info(`Rewrite ${address} to ${awsMessageId}.`);
+        context.mail.raw = context.mail.raw.replaceAll(address, awsMessageId);
+      }
+    }
+    log.info("Done rewrite message ids.");
+  }
+}
+
+export class AwsMailMessageIdSaveHook implements MailDeliverHook {
+  readonly #db;
+
+  constructor(db: DbService) {
+    this.#db = db;
+  }
+
+  async callback(context: MailDeliverContext): Promise<void> {
+    log.info("Save aws message ids...");
+    const messageId = context.mail.startSimpleParse().sections().headers()
+      .messageId();
+    if (messageId == null) {
+      log.info("Original mail does not have message id. Skip saving.");
+      return;
+    }
+    if (context.result.awsMessageId != null) {
+      log.info(`Saving ${messageId} => ${context.result.awsMessageId}.`);
+      await this.#db.addMessageIdMap({
+        message_id: messageId,
+        aws_message_id: context.result.awsMessageId,
+      });
+    }
+    log.info("Done save message ids.");
+  }
+}
+
+export class AwsMailDeliverer extends SyncMailDeliverer {
+  readonly name = "aws";
+  readonly #aws;
+  readonly #ses;
+
+  constructor(aws: AwsContext) {
+    super();
+    this.#aws = aws;
+    this.#ses = new SESv2Client(aws);
+  }
+
+  protected override async doDeliver(
+    mail: Mail,
+    context: MailDeliverContext,
+  ): Promise<void> {
+    log.info("Begin to call aws send-email api...");
+
+    try {
+      const sendCommand = new SendEmailCommand({
+        Content: {
+          Raw: { Data: mail.toUtf8Bytes() },
+        },
+      });
+
+      const res = await this.#ses.send(sendCommand);
+      if (res.MessageId == null) {
+        log.warn("Aws send-email returns no message id.");
+      } else {
+        context.result.awsMessageId =
+          `${res.MessageId}@${this.#aws.region}.amazonses.com`;
+      }
+
+      context.result.recipients.set("*", {
+        kind: "done",
+        message:
+          `Successfully called aws send-email, message id ${context.result.awsMessageId}.`,
+      });
+    } catch (cause) {
+      context.result.recipients.set("*", {
+        kind: "fail",
+        message: "An error was thrown when calling aws send-email." + cause,
+        cause,
+      });
+    }
+  }
+}
diff --git a/deno/mail-relay/aws/retriever.ts b/deno/mail-relay/aws/retriever.ts
new file mode 100644
index 0000000..756cfc3
--- /dev/null
+++ b/deno/mail-relay/aws/retriever.ts
@@ -0,0 +1,100 @@
+/// <reference types="npm:@types/node" />
+
+import {
+  GetObjectCommand,
+  ListObjectsV2Command,
+  S3Client,
+} from "@aws-sdk/client-s3";
+
+import log from "../log.ts";
+import config from "../config.ts";
+import "../better-js.ts";
+
+import { Mail, MailDeliverer } from "../mail.ts";
+import { AwsContext, s3MoveObject } from "./context.ts";
+
+const AWS_SES_S3_SETUP_TAG = "AMAZON_SES_SETUP_NOTIFICATION";
+
+export class AwsMailRetriever {
+  readonly liveMailPrefix = "mail/live/";
+  readonly archiveMailPrefix = "mail/archive/";
+  readonly mailBucket = config.get("awsMailBucket");
+
+  readonly #s3;
+
+  constructor(
+    aws: AwsContext,
+    public readonly inboundDeliverer: MailDeliverer,
+  ) {
+    this.#s3 = new S3Client(aws);
+  }
+
+  async listLiveMails(): Promise<string[]> {
+    log.info("Begin to retrieve live mails.");
+
+    const listCommand = new ListObjectsV2Command({
+      Bucket: this.mailBucket,
+      Prefix: this.liveMailPrefix,
+    });
+    const res = await this.#s3.send(listCommand);
+
+    if (res.Contents == null) {
+      log.warn("Listing live mails in S3 returns null Content.");
+      return [];
+    }
+
+    const result: string[] = [];
+    for (const object of res.Contents) {
+      if (object.Key == null) {
+        log.warn("Listing live mails in S3 returns an object with no Key.");
+        continue;
+      }
+
+      if (object.Key.endsWith(AWS_SES_S3_SETUP_TAG)) continue;
+
+      result.push(object.Key.slice(this.liveMailPrefix.length));
+    }
+    return result;
+  }
+
+  async deliverS3Mail(s3Key: string, recipients: string[] = []) {
+    log.info(`Begin to deliver s3 mail ${s3Key} to ${recipients.join(" ")}...`);
+
+    log.info(`Fetching s3 mail ${s3Key}...`);
+    const mailPath = `${this.liveMailPrefix}${s3Key}`;
+    const command = new GetObjectCommand({
+      Bucket: this.mailBucket,
+      Key: mailPath,
+    });
+    const res = await this.#s3.send(command);
+
+    if (res.Body == null) {
+      throw new Error("S3 mail returns a null body.");
+    }
+
+    const rawMail = await res.Body.transformToString();
+    log.info(`Done fetching s3 mail ${s3Key}.`);
+
+    log.info(`Delivering s3 mail ${s3Key}...`);
+    const mail = new Mail(rawMail);
+    await this.inboundDeliverer.deliver({ mail, recipients: recipients });
+    log.info(`Done delivering s3 mail ${s3Key}.`);
+
+    const date = mail.startSimpleParse().sections().headers().date();
+    const dateString = date?.toFileNameString(true) ?? "invalid-date";
+    const newPath = `${this.archiveMailPrefix}${dateString}/${s3Key}`;
+
+    log.info(`Archiving s3 mail ${s3Key} to ${newPath}...`);
+    await s3MoveObject(this.#s3, this.mailBucket, mailPath, newPath);
+    log.info(`Done delivering s3 mail ${s3Key}...`);
+  }
+
+  async recycleLiveMails() {
+    log.info("Begin to recycle live mails...");
+    const mails = await this.listLiveMails();
+    log.info(`Found ${mails.length} live mails`);
+    for (const s3Key of mails) {
+      await this.deliverS3Mail(s3Key);
+    }
+  }
+}