first commit

libs/api/tracker/application/src/lib/event-handlers/comment-added.event-handler.ts

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+import { EventsHandler, IEventHandler } from '@nestjs/cqrs';
+import { CommentAddedEvent } from '@task-stream/api/tracker/domain';
+import { FindCommentsRepository } from '../ports/find-comments.repository';
+import { UpsertMaterializedCommentRepository } from '../ports/upsert-materialized-comment.repository';
+import { UpsertMaterializedIssueRepository } from '../ports/upsert-materialized-issue.repository';
+import { UserDirectory } from '../ports/user-directory';
+import { ReadModelNotifier, versionOf } from './read-model-notifier';
+
+@EventsHandler(CommentAddedEvent)
+export class CommentAddedEventHandler
+  implements IEventHandler<CommentAddedEvent>
+{
+  constructor(
+    private readonly upsertMaterializedCommentRepository: UpsertMaterializedCommentRepository,
+    private readonly upsertMaterializedIssueRepository: UpsertMaterializedIssueRepository,
+    private readonly findComments: FindCommentsRepository,
+    private readonly users: UserDirectory,
+    private readonly notifier: ReadModelNotifier,
+  ) {}
+
+  async handle(event: CommentAddedEvent) {
+    const { comment } = event;
+    const users = await this.users.refs([comment.authorId]);
+    await this.upsertMaterializedCommentRepository.upsert({
+      id: comment.id,
+      issueId: comment.issueId,
+      projectId: comment.projectId,
+      author: users.of(comment.authorId),
+      body: comment.body,
+      createdAt: comment.createdAt,
+      editedAt: null,
+      version: versionOf(event),
+    });
+    // Recount instead of incrementing, so redelivery stays idempotent.
+    await this.upsertMaterializedIssueRepository.setCommentCount(
+      comment.issueId,
+      await this.findComments.countByIssue(comment.issueId),
+    );
+    await this.notifier.comment(comment.id, comment.issueId, event);
+    await this.notifier.issue(comment.issueId, event);
+  }
+}