refactor: notification logic to createComment() (denoland#568)

Closes denoland#563
dreamcatcher-tech · Sep 11, 2023 · 7149738 · 7149738
1 parent 8043b5e
commit 7149738
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Showing 3 changed files with 40 additions and 29 deletions.
diff --git a/routes/api/comments.ts b/routes/api/comments.ts
@@ -1,7 +1,7 @@
 // Copyright 2023 the Deno authors. All rights reserved. MIT license.
 import type { Handlers } from "$fresh/server.ts";
 import { createHttpError } from "std/http/http_errors.ts";
-import { createComment, createNotification, getItem } from "@/utils/db.ts";
+import { createComment } from "@/utils/db.ts";
 import { redirect } from "@/utils/http.ts";
 import { assertSignedIn, State } from "@/middleware/session.ts";
 import { ulid } from "std/ulid/mod.ts";
@@ -21,27 +21,13 @@ export const handler: Handlers<undefined, State> = {
       throw createHttpError(Status.BadRequest, "Item ID must be a string");
     }
 
-    const item = await getItem(itemId);
-    if (item === null) throw createHttpError(Status.NotFound, "Item not found");
-
-    const { sessionUser } = ctx.state;
     await createComment({
       id: ulid(),
-      userLogin: sessionUser.login,
-      itemId: itemId,
+      userLogin: ctx.state.sessionUser.login,
+      itemId,
       text,
     });
 
-    if (item.userLogin !== sessionUser.login) {
-      await createNotification({
-        id: ulid(),
-        userLogin: item.userLogin,
-        type: "comment",
-        text: `${sessionUser.login} commented on your post: ${item.title}`,
-        originUrl: `/items/${itemId}`,
-      });
-    }
-
     return redirect("/items/" + itemId);
   },
 };
diff --git a/utils/db.ts b/utils/db.ts
@@ -1,5 +1,5 @@
 // Copyright 2023 the Deno authors. All rights reserved. MIT license.
-import { decodeTime } from "std/ulid/mod.ts";
+import { decodeTime, ulid } from "std/ulid/mod.ts";
 import { chunk } from "std/collections/chunk.ts";
 
 const KV_PATH_KEY = "KV_PATH";
@@ -229,17 +229,41 @@ export interface Comment {
 }
 
 export async function createComment(comment: Comment) {
-  const key = [
+  const itemKey = ["items", comment.itemId];
+  const itemRes = await kv.get<Item>(itemKey);
+  const item = itemRes.value;
+  if (item === null) throw new Deno.errors.NotFound("Item not found");
+
+  const commentKey = [
     "comments_by_item",
     comment.itemId,
     comment.id,
   ];
 
-  const res = await kv.atomic()
-    .check({ key, versionstamp: null })
-    .set(key, comment)
-    .commit();
+  const atomicOp = kv.atomic()
+    .check({ key: commentKey, versionstamp: null })
+    .set(commentKey, comment);
+
+  // Create a notification if the item doesn't belong to the user who commented.
+  if (comment.userLogin !== item.userLogin) {
+    const notification: Notification = {
+      id: ulid(decodeTime(comment.id)),
+      userLogin: item.userLogin,
+      type: "comment",
+      text: `${comment.userLogin} commented on your post: ${item.title}`,
+      originUrl: `/items/${item.id}`,
+    };
+    const notificationKey = [
+      "notifications_by_user",
+      notification.userLogin,
+      notification.id,
+    ];
+    atomicOp
+      .check({ key: notificationKey, versionstamp: null })
+      .set(notificationKey, notification);
+  }
 
+  const res = await atomicOp.commit();
   if (!res.ok) throw new Error("Failed to create comment");
 }
 

diff --git a/utils/db_test.ts b/utils/db_test.ts
@@ -165,16 +165,17 @@ Deno.test("[db] visit", async () => {
 });
 
 Deno.test("[db] comments", async () => {
-  const itemId = crypto.randomUUID();
-  const comment1 = { ...genNewComment(), itemId };
-  const comment2 = { ...genNewComment(), itemId };
+  const item = genNewItem();
+  await createItem(item);
+  const comment1: Comment = { ...genNewComment(), itemId: item.id };
+  const comment2: Comment = { ...genNewComment(), itemId: item.id };
 
-  assertEquals(await collectValues(listCommentsByItem(itemId)), []);
+  assertEquals(await collectValues(listCommentsByItem(item.id)), []);
 
   await createComment(comment1);
   await createComment(comment2);
   await assertRejects(async () => await createComment(comment2));
-  assertArrayIncludes(await collectValues(listCommentsByItem(itemId)), [
+  assertArrayIncludes(await collectValues(listCommentsByItem(item.id)), [
     comment1,
     comment2,
   ]);
@@ -185,7 +186,7 @@ Deno.test("[db] comments", async () => {
     async () => await deleteComment(comment1),
     "Comment not found",
   );
-  assertEquals(await collectValues(listCommentsByItem(itemId)), []);
+  assertEquals(await collectValues(listCommentsByItem(item.id)), []);
 });
 
 Deno.test("[db] votes", async () => {