chore: emit export related events on ExportsManager instance

Author: himanshusinghs

src/common/session.ts

@@ -25,8 +25,6 @@ export type SessionEvents = {
     close: [];
     disconnect: [];
     "connection-error": [string];
-    "export-expired": [string];
-    "export-available": [string];
 };
 
 export class Session extends EventEmitter<SessionEvents> {

src/common/sessionExportsManager.ts

@@ -1,6 +1,7 @@
 import z from "zod";
 import path from "path";
 import fs from "fs/promises";
+import EventEmitter from "events";
 import { createWriteStream } from "fs";
 import { lock } from "proper-lockfile";
 import { FindCursor } from "mongodb";
@@ -28,7 +29,12 @@ export type SessionExportsManagerConfig = Pick<
 
 const MAX_LOCK_RETRIES = 10;
 
-export class SessionExportsManager {
+type SessionExportsManagerEvents = {
+    "export-expired": [string];
+    "export-available": [string];
+};
+
+export class SessionExportsManager extends EventEmitter<SessionExportsManagerEvents> {
     private availableExports: Export[] = [];
     private exportsCleanupInterval: NodeJS.Timeout;
     private exportsCleanupInProgress: boolean = false;
@@ -37,6 +43,7 @@ export class SessionExportsManager {
         private readonly session: Session,
         private readonly config: SessionExportsManagerConfig
     ) {
+        super();
         this.exportsCleanupInterval = setInterval(
             () => void this.cleanupExpiredExports(),
             this.config.exportCleanupIntervalMs
@@ -149,7 +156,7 @@ export class SessionExportsManager {
                                 uri: resourceURI,
                             },
                         ];
-                        this.session.emit("export-available", resourceURI);
+                        this.emit("export-available", resourceURI);
                     }
                 }
             });
@@ -212,7 +219,7 @@ export class SessionExportsManager {
                     if (await this.isExportFileExpired(exportPath)) {
                         await fs.unlink(exportPath);
                         this.availableExports = this.availableExports.filter(({ name }) => name !== exportName);
-                        this.session.emit("export-expired", this.exportNameToResourceURI(exportName));
+                        this.emit("export-expired", this.exportNameToResourceURI(exportName));
                     }
                 }
             });

src/resources/common/exportedData.ts

@@ -13,13 +13,13 @@ export class ExportedData {
     private readonly uri = "exported-data://{exportName}";
 
     constructor(private readonly server: Server) {
-        this.server.session.on("export-available", (uri) => {
+        this.server.exportsManager.on("export-available", (uri) => {
             this.server.mcpServer.sendResourceListChanged();
             void this.server.mcpServer.server.sendResourceUpdated({
                 uri,
             });
         });
-        this.server.session.on("export-expired", () => {
+        this.server.exportsManager.on("export-expired", () => {
             this.server.mcpServer.sendResourceListChanged();
         });
     }

tests/unit/common/sessionExportsManager.test.ts

@@ -152,7 +152,7 @@ describe("SessionExportsManager integration test", () => {
             it("should create an empty export", async () => {
                 inputCursor = createDummyFindCursor([]);
 
-                const emitSpy = vi.spyOn(session, "emit");
+                const emitSpy = vi.spyOn(manager, "emit");
                 await manager.createJSONExport({
                     input: inputCursor,
                     exportName,
@@ -183,7 +183,7 @@ describe("SessionExportsManager integration test", () => {
             { cond: "when exportName contains extension", exportName: `foo.bar.${Date.now()}.json` },
         ])("$cond", ({ exportName }) => {
             it("should export relaxed json, update available exports and emit export-available event", async () => {
-                const emitSpy = vi.spyOn(session, "emit");
+                const emitSpy = vi.spyOn(manager, "emit");
                 await manager.createJSONExport({
                     input: inputCursor,
                     exportName,
@@ -216,7 +216,7 @@ describe("SessionExportsManager integration test", () => {
             { cond: "when exportName contains extension", exportName: `foo.bar.${Date.now()}.json` },
         ])("$cond", ({ exportName }) => {
             it("should export canonical json, update available exports and emit export-available event", async () => {
-                const emitSpy = vi.spyOn(session, "emit");
+                const emitSpy = vi.spyOn(manager, "emit");
                 await manager.createJSONExport({
                     input: inputCursor,
                     exportName,
@@ -250,7 +250,7 @@ describe("SessionExportsManager integration test", () => {
 
         describe("when transform stream throws an error", () => {
             it("should remove the partial export and never make it available", async () => {
-                const emitSpy = vi.spyOn(session, "emit");
+                const emitSpy = vi.spyOn(manager, "emit");
                 // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access, @typescript-eslint/no-explicit-any
                 (manager as any).docToEJSONStream = function (ejsonOptions: EJSONOptions | undefined) {
                     let docsTransformed = 0;