Set up ttl queue

.vscode/settings.json

@@ -1,5 +1,6 @@
 {
   "deno.enable": true,
+  "deno.unstable": true,
   "editor.formatOnSave": true,
   "editor.defaultFormatter": "esbenp.prettier-vscode",
   "[typescript]": {

app/app.ts

@@ -11,6 +11,10 @@ export const SHORTER_DESTINATION = "destination";
 export const SHORTER_DESTINATION_DESCRIPTION =
   "The destination of the shortlink.";
 
+export const SHORTER_TTL = "ttl";
+export const SHORTER_TTL_DESCRIPTION =
+  "The time-to-live of the shortlink (e.g. `1d`, `1w`, `1m`, `1y`, etc.).";
+
 /**
  * APP_SHORTER is the top-level command for the Shorter Application Command.
  */
@@ -31,5 +35,10 @@ export const APP_SHORTER: discord.RESTPostAPIApplicationCommandsJSONBody = {
       description: SHORTER_DESTINATION_DESCRIPTION,
       required: true,
     },
+    {
+      type: discord.ApplicationCommandOptionType.String,
+      name: SHORTER_TTL,
+      description: SHORTER_TTL_DESCRIPTION,
+    },
   ],
 };

deps.ts

@@ -1,5 +1,6 @@
-export * as dotenv from "https://deno.land/std@0.201.0/dotenv/mod.ts";
-export * as discord from "https://deno.land/x/[email protected].56/v10.ts";
+export * as dotenv from "https://deno.land/std@0.203.0/dotenv/mod.ts";
+export * as discord from "https://deno.land/x/[email protected].58/v10.ts";
 export * from "https://deno.land/x/[email protected]/github/mod.ts";
 export type { GitHubAPIClientOptions } from "https://deno.land/x/[email protected]/github/api/mod.ts";
+export { Duration } from "https://deno.land/x/[email protected]/mod.ts";
 export { default as nacl } from "https://esm.sh/[email protected]";

main.ts

@@ -4,11 +4,17 @@
 // deno task ngrok
 //
 
-import { discord } from "./deps.ts";
+import { discord, Duration } from "./deps.ts";
 import { DiscordAPIClient, verify } from "./discord/mod.ts";
-import { APP_SHORTER, SHORTER_ALIAS, SHORTER_DESTINATION } from "./app/mod.ts";
+import {
+  APP_SHORTER,
+  SHORTER_ALIAS,
+  SHORTER_DESTINATION,
+  SHORTER_TTL,
+} from "./app/mod.ts";
 import type { ShorterOptions } from "./shorter.ts";
 import { shorter } from "./shorter.ts";
+import { addTTLMessage, listenToTTLChannel } from "./queue.ts";
 import * as env from "./env.ts";
 
 const api = new DiscordAPIClient();
@@ -20,9 +26,16 @@ if (import.meta.main) {
 /**
  * main is the entrypoint for the Shorter application command.
  */
-export function main() {
+export async function main() {
+  // Set up queue listener.
+  const kv = await Deno.openKv();
+  kv.listenQueue(listenToTTLChannel);
+
   // Start the server.
-  Deno.serve({ port: env.PORT, onListen }, handle);
+  Deno.serve(
+    { port: env.PORT, onListen },
+    makeHandler(kv),
+  );
 }
 
 async function onListen() {
@@ -41,88 +54,114 @@ async function onListen() {
 }
 
 /**
- * handle is the HTTP handler for the Shorter application command.
+ * makeHandler makes the HTTP handler for the Shorter application command.
  */
-export async function handle(request: Request): Promise<Response> {
-  // Redirect to the invite URL on GET /invite.
-  const url = new URL(request.url);
-  if (request.method === "GET" && url.pathname === "/invite") {
-    return Response.redirect(INVITE_URL);
-  }
-
-  // Verify the request.
-  const { error, body } = await verify(request, env.DISCORD_PUBLIC_KEY);
-  if (error !== null) {
-    return error;
-  }
-
-  // Parse the incoming request as JSON.
-  const interaction = await JSON.parse(body) as discord.APIInteraction;
-  switch (interaction.type) {
-    case discord.InteractionType.Ping: {
-      return Response.json({ type: discord.InteractionResponseType.Pong });
+export function makeHandler(kv: Deno.Kv) {
+  /**
+   * handle is the HTTP handler for the Shorter application command.
+   */
+  return async function handle(request: Request): Promise<Response> {
+    // Redirect to the invite URL on GET /invite.
+    const url = new URL(request.url);
+    if (request.method === "GET" && url.pathname === "/invite") {
+      return Response.redirect(INVITE_URL);
     }
 
-    case discord.InteractionType.ApplicationCommand: {
-      if (
-        !discord.Utils.isChatInputApplicationCommandInteraction(interaction)
-      ) {
-        return new Response("Invalid request", { status: 400 });
-      }
+    // Verify the request.
+    const { error, body } = await verify(request, env.DISCORD_PUBLIC_KEY);
+    if (error !== null) {
+      return error;
+    }
 
-      if (!interaction.member?.user) {
-        return new Response("Invalid request", { status: 400 });
+    // Parse the incoming request as JSON.
+    const interaction = await JSON.parse(body) as discord.APIInteraction;
+    switch (interaction.type) {
+      case discord.InteractionType.Ping: {
+        return Response.json({ type: discord.InteractionResponseType.Pong });
       }
 
-      if (
-        !interaction.member.roles.some((role) => env.DISCORD_ROLE_ID === role)
-      ) {
-        return new Response("Invalid request", { status: 400 });
-      }
-
-      // Make the Shorter options.
-      const options = makeShorterOptions(
-        interaction.member,
-        interaction.data,
-      );
-
-      // Invoke the Shorter operation.
-      shorter(options)
-        .then((result) =>
-          api.editOriginalInteractionResponse({
-            botID: env.DISCORD_CLIENT_ID,
-            botToken: env.DISCORD_TOKEN,
-            interactionToken: interaction.token,
-            content:
-              `Created commit [${result.message}](https://acmcsuf.com/code/commit/${result.sha})!`,
-          })
-        )
-        .catch((error) => {
-          if (error instanceof Error) {
-            api.editOriginalInteractionResponse({
+      case discord.InteractionType.ApplicationCommand: {
+        if (
+          !discord.Utils.isChatInputApplicationCommandInteraction(interaction)
+        ) {
+          return new Response("Invalid request", { status: 400 });
+        }
+
+        if (!interaction.member?.user) {
+          return new Response("Invalid request", { status: 400 });
+        }
+
+        if (
+          !interaction.member.roles.some((role) => env.DISCORD_ROLE_ID === role)
+        ) {
+          return new Response("Invalid request", { status: 400 });
+        }
+
+        // Make the Shorter options.
+        const options = makeShorterOptions(
+          interaction.member,
+          interaction.data,
+        );
+
+        // Invoke the Shorter operation.
+        shorter(options)
+          .then(async (result) => {
+            // Send the success message.
+            await api.editOriginalInteractionResponse({
               botID: env.DISCORD_CLIENT_ID,
               botToken: env.DISCORD_TOKEN,
               interactionToken: interaction.token,
-              content: `Error: ${error.message}`,
+              content:
+                `Created commit [${result.message}](https://acmcsuf.com/code/commit/${result.sha})!`,
             });
-          }
-
-          console.error(error);
-        });
-
-      // Acknowledge the interaction.
-      return Response.json(
-        {
-          type:
-            discord.InteractionResponseType.DeferredChannelMessageWithSource,
-        } satisfies discord.APIInteractionResponseDeferredChannelMessageWithSource,
-      );
-    }
 
-    default: {
-      return new Response("Invalid request", { status: 400 });
+            // Get the TTL option.
+            const ttlOption = interaction.data.options
+              ?.find((option) => option.name === SHORTER_TTL);
+            if (ttlOption) {
+              if (
+                ttlOption.type !== discord.ApplicationCommandOptionType.String
+              ) {
+                throw new Error("Invalid TTL");
+              }
+
+              // Parse the TTL in milliseconds.
+              const ttlDuration = Duration.fromString(ttlOption.value).raw;
+
+              // Enqueue the delete operation.
+              await addTTLMessage(kv, {
+                alias: options.data.alias,
+                actor: options.actor,
+              }, ttlDuration);
+            }
+          })
+          .catch((error) => {
+            if (error instanceof Error) {
+              api.editOriginalInteractionResponse({
+                botID: env.DISCORD_CLIENT_ID,
+                botToken: env.DISCORD_TOKEN,
+                interactionToken: interaction.token,
+                content: `Error: ${error.message}`,
+              });
+            }
+
+            console.error(error);
+          });
+
+        // Acknowledge the interaction.
+        return Response.json(
+          {
+            type:
+              discord.InteractionResponseType.DeferredChannelMessageWithSource,
+          } satisfies discord.APIInteractionResponseDeferredChannelMessageWithSource,
+        );
+      }
+
+      default: {
+        return new Response("Invalid request", { status: 400 });
+      }
     }
-  }
+  };
 }
 
 /**

queue.ts

@@ -0,0 +1,50 @@
+import type { ShorterOptions } from "./shorter.ts";
+import { shorter } from "./shorter.ts";
+import * as env from "./env.ts";
+
+/**
+ * TTLMessage is a message received from the TTL channel.
+ */
+export interface TTLMessage {
+  channel: "ttl";
+  data: {
+    alias: string;
+    actor: ShorterOptions["actor"];
+  };
+}
+
+/**
+ * listenToTTLChannel listens to the TTL channel.
+ */
+export function listenToTTLChannel(m: unknown) {
+  if ((m as TTLMessage).channel === "ttl") {
+    const data = (m as TTLMessage).data;
+
+    // Remove the shortlink from persisted storage.
+    shorter({
+      githubPAT: env.GITHUB_TOKEN,
+      actor: data.actor,
+      // Omitting the destination will remove the alias.
+      data: { alias: data.alias },
+    })
+      .catch((error) => {
+        if (error instanceof Error) {
+          console.error(error);
+        }
+      });
+  }
+}
+
+/**
+ * addTTLMessage adds a TTL message to the TTL channel.
+ */
+export async function addTTLMessage(
+  kv: Deno.Kv,
+  data: TTLMessage["data"],
+  delay: number,
+) {
+  return await kv.enqueue(
+    { channel: "ttl", data },
+    { delay },
+  );
+}

shorter.ts

@@ -19,7 +19,12 @@ export async function shorter(options: ShorterOptions): Promise<ShorterResult> {
               );
             }
 
-            data[options.data.alias] = options.data.destination;
+            if (options.data.destination === undefined) {
+              delete data[options.data.alias];
+            } else {
+              data[options.data.alias] = options.data.destination;
+            }
+
             return JSON.stringify(data, null, 2) + "\n";
           })
       )
@@ -78,8 +83,10 @@ export interface ShorterOptions {
 
     /**
      * destination is the destination location.
+     *
+     * If destination is not provided, the alias will be removed.
      */
-    destination: string;
+    destination?: string;
   };
 }
 
@@ -98,15 +105,6 @@ export interface ShorterResult {
   message: string;
 }
 
-/**
- * ShorterError is an error that occurs during shortening.
- */
-export class ShorterError extends Error {
-  public constructor(message: string) {
-    super(message);
-  }
-}
-
 function formatCommitMessage(options: ShorterOptions): string {
   return `update \`/${options.data.alias}\` shortlink`;
 }