feat: history cleanup (#7007)

fix AFF-1069

packages/backend/server/src/plugins/copilot/resolver.ts

@@ -1,6 +1,6 @@
 import { createHash } from 'node:crypto';
 
-import { BadRequestException, Logger } from '@nestjs/common';
+import { BadRequestException, Logger, NotFoundException } from '@nestjs/common';
 import {
   Args,
   Field,
@@ -55,6 +55,18 @@ class CreateChatSessionInput {
   promptName!: string;
 }
 
+@InputType()
+class DeleteSessionInput {
+  @Field(() => String)
+  workspaceId!: string;
+
+  @Field(() => String)
+  docId!: string;
+
+  @Field(() => [String])
+  sessionIds!: string[];
+}
+
 @InputType()
 class CreateChatMessageInput implements Omit<SubmittedMessage, 'content'> {
   @Field(() => String)
@@ -264,6 +276,35 @@ export class CopilotResolver {
     return session;
   }
 
+  @Mutation(() => String, {
+    description: 'Cleanup sessions',
+  })
+  async cleanupCopilotSession(
+    @CurrentUser() user: CurrentUser,
+    @Args({ name: 'options', type: () => DeleteSessionInput })
+    options: DeleteSessionInput
+  ) {
+    await this.permissions.checkCloudPagePermission(
+      options.workspaceId,
+      options.docId,
+      user.id
+    );
+    if (!options.sessionIds.length) {
+      return new NotFoundException('Session not found');
+    }
+    const lockFlag = `${COPILOT_LOCKER}:session:${user.id}:${options.workspaceId}`;
+    await using lock = await this.mutex.lock(lockFlag);
+    if (!lock) {
+      return new TooManyRequestsException('Server is busy');
+    }
+
+    const ret = await this.chatSession.cleanup({
+      ...options,
+      userId: user.id,
+    });
+    return ret;
+  }
+
   @Mutation(() => String, {
     description: 'Create a chat message',
   })