1 files changed, 90 insertions, 0 deletions
diff --git a/services/docker/mail-server/aws-sendmail/aws/retriever.ts b/services/docker/mail-server/aws-sendmail/aws/retriever.ts
new file mode 100644
index 0000000..de577b0
--- /dev/null
+++ b/services/docker/mail-server/aws-sendmail/aws/retriever.ts
@@ -0,0 +1,90 @@
+/// <reference types="npm:@types/node" />
+
+import {
+  GetObjectCommand,
+  ListObjectsV2Command,
+  S3Client,
+} from "@aws-sdk/client-s3";
+
+import { AwsContext, s3MoveObject } from "./context.ts";
+import { getLogger } from "../logger.ts";
+import { getConfig } from "../config.ts";
+import { Mail } from "../mail.ts";
+
+export class AwsMailRetriever {
+  readonly liveMailPrefix = "mail/live/";
+  readonly archiveMailPrefix = "mail/archive/";
+  readonly mailBucket = getConfig().getValue("awsMailBucket");
+
+  private readonly s3Client;
+
+  constructor(
+    aws: AwsContext,
+    private readonly callback: (mail: Mail) => Promise<void>,
+  ) {
+    const { region, credentials } = aws;
+    this.s3Client = new S3Client({ region, credentials });
+  }
+
+  async listLiveMails(): Promise<string[]> {
+    const listCommand = new ListObjectsV2Command({
+      Bucket: this.mailBucket,
+      Prefix: this.liveMailPrefix,
+    });
+    const res = await this.s3Client.send(listCommand);
+
+    if (res.Contents == null) {
+      getLogger().warn("Listing live mails in S3 returns null Content.");
+      return [];
+    }
+
+    const result: string[] = [];
+    for (const object of res.Contents) {
+      if (object.Key != null) {
+        // TODO: check prefix consistence here.
+        result.push(object.Key.slice(this.liveMailPrefix.length));
+      } else {
+        getLogger().warn(
+          "Listing live mails in S3 returns an object with no Key.",
+        );
+      }
+    }
+    return result;
+  }
+
+  async deliverS3MailObject(messageId: string) {
+    const mailPath = `${this.liveMailPrefix}${messageId}`;
+    const command = new GetObjectCommand({
+      Bucket: this.mailBucket,
+      Key: mailPath,
+    });
+    const res = await this.s3Client.send(command);
+
+    if (res.Body == null) {
+      // TODO: Better error.
+      throw new Error();
+    }
+
+    const rawMail = await res.Body.transformToString();
+    const mail = new Mail(rawMail);
+    mail.awsMessageId = messageId;
+    await this.callback(mail);
+
+    // TODO: Continue here.
+    await s3MoveObject(
+      this.s3Client,
+      this.mailBucket,
+      mailPath,
+      `${this.archiveMailPrefix}${
+        mail.simpleGetDateString("invalid-date")
+      }/${messageId}`,
+    );
+  }
+
+  async recycleLiveMails() {
+    const mails = await this.listLiveMails();
+    for (const messageId of mails) {
+      await this.deliverS3MailObject(messageId);
+    }
+  }
+}