fix delete session after tests to avoid resource leak

Previously sessions were not deleted, leaving device connections and port forwarding open.
Now sessions are explicitly deleted, ensuring proper cleanup of resources.

Author: aRaikoFunakami

src/server.ts

@@ -1,6 +1,7 @@
 import { FastMCP } from 'fastmcp';
 import registerTools from './tools/index.js';
 import registerResources from './resources/index.js';
+import { hasActiveSession, safeDeleteSession } from './tools/sessionStore.js';
 
 const server = new FastMCP({
   name: 'Jarvis Appium',
@@ -11,4 +12,28 @@ const server = new FastMCP({
 
 registerResources(server);
 registerTools(server);
+
+// Handle client connection and disconnection events
+server.on("connect", (event) => {
+  console.log("Client connected:", event.session);
+});
+
+server.on("disconnect", async (event) => {
+  console.log("Client disconnected:", event.session);
+  // Only try to clean up if there's an active session
+  if (hasActiveSession()) {
+    try {
+      console.log("Active session detected on disconnect, cleaning up...");
+      const deleted = await safeDeleteSession();
+      if (deleted) {
+        console.log("Session cleaned up successfully on disconnect.");
+      }
+    } catch (error) {
+      console.error("Error cleaning up session on disconnect:", error);
+    }
+  } else {
+    console.log("No active session to clean up on disconnect.");
+  }
+});
+
 export default server;

src/tools/create-session.ts

@@ -3,10 +3,9 @@
  */
 import { z } from 'zod';
 import fs from 'fs';
-import path from 'path';
 import { AndroidUiautomator2Driver } from 'appium-uiautomator2-driver';
 import { XCUITestDriver } from 'appium-xcuitest-driver';
-import { setSession, getDriver, getSessionId } from './sessionStore.js';
+import { setSession, hasActiveSession, safeDeleteSession } from './sessionStore.js';
 
 // Define capabilities type
 interface Capabilities {
@@ -44,6 +43,12 @@ export default function createSession(server: any): void {
     },
     execute: async (args: any, context: any): Promise<any> => {
       try {
+        // Check if there's an existing session and clean it up first
+        if (hasActiveSession()) {
+          console.log('Existing session detected, cleaning up before creating new session...');
+          await safeDeleteSession();
+        }
+
         const { platform, capabilities: customCapabilities } = args;
 
         let defaultCapabilities: Capabilities;

src/tools/delete-session.ts

@@ -0,0 +1,46 @@
+/**
+ * Tool to delete the current mobile session and clean up resources
+ */
+import { z } from 'zod';
+import { safeDeleteSession } from './sessionStore.js';
+
+export default function deleteSession(server: any): void {
+  server.addTool({
+    name: 'delete_session',
+    description: 'Delete the current mobile session and clean up resources.',
+    parameters: z.object({}),
+    annotations: {
+      destructiveHint: true,
+      readOnlyHint: false,
+      openWorldHint: false,
+    },
+    execute: async (): Promise<any> => {
+      try {
+        const deleted = await safeDeleteSession();
+        
+        if (deleted) {
+          return {
+            content: [
+              {
+                type: 'text',
+                text: 'Session deleted successfully.',
+              },
+            ],
+          };
+        } else {
+          return {
+            content: [
+              {
+                type: 'text',
+                text: 'No active session found or deletion already in progress.',
+              },
+            ],
+          };
+        }
+      } catch (error: any) {
+        console.error(`Error deleting session`, error);
+        throw new Error(`Failed to delete session: ${error.message}`);
+      }
+    },
+  });
+}

src/tools/index.ts

@@ -1,6 +1,7 @@
 import { FastMCP } from 'fastmcp/dist/FastMCP.js';
 import answerAppium from './answerAppium.js';
 import createSession from './create-session.js';
+import deleteSession from './delete-session.js';
 import createCloudSession from './create-cloud-session.js';
 import uploadApp from './upload-app.js';
 import generateLocators from './locators.js';
@@ -19,6 +20,7 @@ import terminateApp from './interactions/terminateApp.js';
 export default function registerTools(server: FastMCP): void {
   selectPlatform(server);
   createSession(server);
+  deleteSession(server);
   createCloudSession(server);
   uploadApp(server);
   generateLocators(server);

src/tools/sessionStore.ts

@@ -3,10 +3,15 @@ import { XCUITestDriver } from 'appium-xcuitest-driver';
 
 let driver: any = null;
 let sessionId: string | null = null;
+let isDeletingSession = false; // Lock to prevent concurrent deletion
 
-export function setSession(d: any, id: string) {
+export function setSession(d: any, id: string | null) {
   driver = d;
   sessionId = id;
+  // Reset deletion flag when setting a new session
+  if (d && id) {
+    isDeletingSession = false;
+  }
 }
 
 export function getDriver() {
@@ -17,6 +22,49 @@ export function getSessionId() {
   return sessionId;
 }
 
+export function isDeletingSessionInProgress() {
+  return isDeletingSession;
+}
+
+export function hasActiveSession(): boolean {
+  return driver !== null && sessionId !== null && !isDeletingSession;
+}
+
+export async function safeDeleteSession(): Promise<boolean> {
+  // Check if there's no session to delete
+  if (!driver || !sessionId) {
+    console.log('No active session to delete.');
+    return false;
+  }
+
+  // Check if deletion is already in progress
+  if (isDeletingSession) {
+    console.log('Session deletion already in progress, skipping...');
+    return false;
+  }
+
+  // Set lock
+  isDeletingSession = true;
+
+  try {
+    console.log('Deleting current session');
+    await driver.deleteSession();
+    
+    // Clear the session from store
+    driver = null;
+    sessionId = null;
+    
+    console.log('Session deleted successfully.');
+    return true;
+  } catch (error) {
+    console.error('Error deleting session:', error);
+    throw error;
+  } finally {
+    // Always release lock
+    isDeletingSession = false;
+  }
+}
+
 export const getPlatformName = (driver: any): string => {
   if (driver instanceof AndroidUiautomator2Driver) return 'Android';
   if (driver instanceof XCUITestDriver) return 'iOS';