From c75d64f1740c4d68f4171f48f274a12666824e16 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 29 Oct 2025 15:48:39 +0000
Subject: [PATCH 1/3] Initial plan


From 0843388d2905f1bab96ab5e2fd34881b9d348aa1 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 29 Oct 2025 15:53:01 +0000
Subject: [PATCH 2/3] Initial exploration - understanding the codebase

Co-authored-by: buckett <5921+buckett@users.noreply.github.com>
---
 package-lock.json           |  15 +-
 public/mockServiceWorker.js | 295 ++++++++++++++++++++++++++++++++++++
 2 files changed, 297 insertions(+), 13 deletions(-)
 create mode 100644 public/mockServiceWorker.js

diff --git a/package-lock.json b/package-lock.json
index 70ff682..2372238 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1806,7 +1806,6 @@
           "url": "https://opencollective.com/csstools"
         }
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       },
@@ -1829,7 +1828,6 @@
           "url": "https://opencollective.com/csstools"
         }
       ],
-      "peer": true,
       "engines": {
         "node": ">=18"
       }
@@ -4511,7 +4509,6 @@
       "resolved": "https://registry.npmjs.org/@testing-library/dom/-/dom-10.4.0.tgz",
       "integrity": "sha512-pemlzrSESWbdAloYml3bAJMEfNh1Z7EduzqPKprCH5S341frlpYnUEW0H72dLxa6IsYr+mPno20GiSm+h9dEdQ==",
       "dev": true,
-      "peer": true,
       "dependencies": {
         "@babel/code-frame": "^7.10.4",
         "@babel/runtime": "^7.12.5",
@@ -4746,7 +4743,8 @@
       "version": "15.7.14",
       "resolved": "https://registry.npmjs.org/@types/prop-types/-/prop-types-15.7.14.tgz",
       "integrity": "sha512-gNMvNH49DJ7OJYv+KAKn0Xp45p8PLl6zo2YnvDIbTd4J6MER2BmWN49TG7n9LvkyihINxeKW8+3bfS2yDC9dzQ==",
-      "dev": true
+      "dev": true,
+      "peer": true
     },
     "node_modules/@types/react": {
       "version": "18.3.23",
@@ -5180,7 +5178,6 @@
           "url": "https://github.com/sponsors/ai"
         }
       ],
-      "peer": true,
       "dependencies": {
         "caniuse-lite": "^1.0.30001716",
         "electron-to-chromium": "^1.5.149",
@@ -5909,7 +5906,6 @@
       "integrity": "sha512-8pgjLUcUjcgDg+2Q4NYXnPbo/vncAY4UmyaCm0jZevERqCHZIaWwdJHkf8XQtu4AxSKCdvrUbT0XUr1IdZzI8Q==",
       "dev": true,
       "hasInstallScript": true,
-      "peer": true,
       "bin": {
         "esbuild": "bin/esbuild"
       },
@@ -6917,7 +6913,6 @@
       "resolved": "https://registry.npmjs.org/jsdom/-/jsdom-25.0.1.tgz",
       "integrity": "sha512-8i7LzZj7BF8uplX+ZyOlIz86V6TAsSs+np6m1kpW9u0JWi4z/1t+FzcK1aek+ybTnAC4KhBL4uXCNT0wcUIeCw==",
       "dev": true,
-      "peer": true,
       "dependencies": {
         "cssstyle": "^4.1.0",
         "data-urls": "^5.0.0",
@@ -7352,7 +7347,6 @@
       "integrity": "sha512-npfIIVRHKQX3Lw4aLWX4wBh+lQwpqdZNyJYB5K/+ktK8NhtkdsTxGK7WDrgknozcVyRI7TOqY6yBS9j2FTR+YQ==",
       "dev": true,
       "hasInstallScript": true,
-      "peer": true,
       "dependencies": {
         "@bundled-es-modules/cookie": "^2.0.1",
         "@bundled-es-modules/statuses": "^1.0.1",
@@ -8072,7 +8066,6 @@
       "resolved": "https://registry.npmjs.org/react/-/react-18.3.1.tgz",
       "integrity": "sha512-wS+hAgJShR0KhEvPJArfuPVN1+Hz1t0Y6n5jLrGQbkb4urgPE/0Rve+1kMB1v/oWgHgm4WIcV+i7F2pTVj+2iQ==",
       "dev": true,
-      "peer": true,
       "dependencies": {
         "loose-envify": "^1.1.0"
       },
@@ -8115,7 +8108,6 @@
       "resolved": "https://registry.npmjs.org/react-dom/-/react-dom-18.3.1.tgz",
       "integrity": "sha512-5m4nQKp+rZRb09LNH59GM4BxTh9251/ylbKIbpe7TpGxfJ+9kv6BLkLBXIjjspbgbnIBNqlI23tRnTWT0snUIw==",
       "dev": true,
-      "peer": true,
       "dependencies": {
         "loose-envify": "^1.1.0",
         "scheduler": "^0.23.2"
@@ -8369,7 +8361,6 @@
       "resolved": "https://registry.npmjs.org/rollup/-/rollup-4.40.2.tgz",
       "integrity": "sha512-tfUOg6DTP4rhQ3VjOO6B4wyrJnGOX85requAXvqYTHsOgb2TFJdZ3aWpT8W2kPoypSGP7dZUyzxJ9ee4buM5Fg==",
       "dev": true,
-      "peer": true,
       "dependencies": {
         "@types/estree": "1.0.7"
       },
@@ -8635,7 +8626,6 @@
       "resolved": "https://registry.npmjs.org/storybook/-/storybook-8.6.12.tgz",
       "integrity": "sha512-Z/nWYEHBTLK1ZBtAWdhxC0l5zf7ioJ7G4+zYqtTdYeb67gTnxNj80gehf8o8QY9L2zA2+eyMRGLC2V5fI7Z3Tw==",
       "dev": true,
-      "peer": true,
       "dependencies": {
         "@storybook/core": "8.6.12"
       },
@@ -9217,7 +9207,6 @@
       "resolved": "https://registry.npmjs.org/vite/-/vite-6.3.5.tgz",
       "integrity": "sha512-cZn6NDFE7wdTpINgs++ZJ4N49W2vRp8LCKrn3Ob1kYNtOo21vfDoaV5GzBfLU4MovSAB8uNRm4jgzVQZ+mBzPQ==",
       "dev": true,
-      "peer": true,
       "dependencies": {
         "esbuild": "^0.25.0",
         "fdir": "^6.4.4",
diff --git a/public/mockServiceWorker.js b/public/mockServiceWorker.js
new file mode 100644
index 0000000..fead0b3
--- /dev/null
+++ b/public/mockServiceWorker.js
@@ -0,0 +1,295 @@
+/* eslint-disable */
+/* tslint:disable */
+
+/**
+ * Mock Service Worker.
+ * @see https://github.com/mswjs/msw
+ * - Please do NOT modify this file.
+ * - Please do NOT serve this file on production.
+ */
+
+const PACKAGE_VERSION = '2.6.6'
+const INTEGRITY_CHECKSUM = 'ca7800994cc8bfb5eb961e037c877074'
+const IS_MOCKED_RESPONSE = Symbol('isMockedResponse')
+const activeClientIds = new Set()
+
+self.addEventListener('install', function () {
+  self.skipWaiting()
+})
+
+self.addEventListener('activate', function (event) {
+  event.waitUntil(self.clients.claim())
+})
+
+self.addEventListener('message', async function (event) {
+  const clientId = event.source.id
+
+  if (!clientId || !self.clients) {
+    return
+  }
+
+  const client = await self.clients.get(clientId)
+
+  if (!client) {
+    return
+  }
+
+  const allClients = await self.clients.matchAll({
+    type: 'window',
+  })
+
+  switch (event.data) {
+    case 'KEEPALIVE_REQUEST': {
+      sendToClient(client, {
+        type: 'KEEPALIVE_RESPONSE',
+      })
+      break
+    }
+
+    case 'INTEGRITY_CHECK_REQUEST': {
+      sendToClient(client, {
+        type: 'INTEGRITY_CHECK_RESPONSE',
+        payload: {
+          packageVersion: PACKAGE_VERSION,
+          checksum: INTEGRITY_CHECKSUM,
+        },
+      })
+      break
+    }
+
+    case 'MOCK_ACTIVATE': {
+      activeClientIds.add(clientId)
+
+      sendToClient(client, {
+        type: 'MOCKING_ENABLED',
+        payload: {
+          client: {
+            id: client.id,
+            frameType: client.frameType,
+          },
+        },
+      })
+      break
+    }
+
+    case 'MOCK_DEACTIVATE': {
+      activeClientIds.delete(clientId)
+      break
+    }
+
+    case 'CLIENT_CLOSED': {
+      activeClientIds.delete(clientId)
+
+      const remainingClients = allClients.filter((client) => {
+        return client.id !== clientId
+      })
+
+      // Unregister itself when there are no more clients
+      if (remainingClients.length === 0) {
+        self.registration.unregister()
+      }
+
+      break
+    }
+  }
+})
+
+self.addEventListener('fetch', function (event) {
+  const { request } = event
+
+  // Bypass navigation requests.
+  if (request.mode === 'navigate') {
+    return
+  }
+
+  // Opening the DevTools triggers the "only-if-cached" request
+  // that cannot be handled by the worker. Bypass such requests.
+  if (request.cache === 'only-if-cached' && request.mode !== 'same-origin') {
+    return
+  }
+
+  // Bypass all requests when there are no active clients.
+  // Prevents the self-unregistered worked from handling requests
+  // after it's been deleted (still remains active until the next reload).
+  if (activeClientIds.size === 0) {
+    return
+  }
+
+  // Generate unique request ID.
+  const requestId = crypto.randomUUID()
+  event.respondWith(handleRequest(event, requestId))
+})
+
+async function handleRequest(event, requestId) {
+  const client = await resolveMainClient(event)
+  const response = await getResponse(event, client, requestId)
+
+  // Send back the response clone for the "response:*" life-cycle events.
+  // Ensure MSW is active and ready to handle the message, otherwise
+  // this message will pend indefinitely.
+  if (client && activeClientIds.has(client.id)) {
+    ;(async function () {
+      const responseClone = response.clone()
+
+      sendToClient(
+        client,
+        {
+          type: 'RESPONSE',
+          payload: {
+            requestId,
+            isMockedResponse: IS_MOCKED_RESPONSE in response,
+            type: responseClone.type,
+            status: responseClone.status,
+            statusText: responseClone.statusText,
+            body: responseClone.body,
+            headers: Object.fromEntries(responseClone.headers.entries()),
+          },
+        },
+        [responseClone.body],
+      )
+    })()
+  }
+
+  return response
+}
+
+// Resolve the main client for the given event.
+// Client that issues a request doesn't necessarily equal the client
+// that registered the worker. It's with the latter the worker should
+// communicate with during the response resolving phase.
+async function resolveMainClient(event) {
+  const client = await self.clients.get(event.clientId)
+
+  if (activeClientIds.has(event.clientId)) {
+    return client
+  }
+
+  if (client?.frameType === 'top-level') {
+    return client
+  }
+
+  const allClients = await self.clients.matchAll({
+    type: 'window',
+  })
+
+  return allClients
+    .filter((client) => {
+      // Get only those clients that are currently visible.
+      return client.visibilityState === 'visible'
+    })
+    .find((client) => {
+      // Find the client ID that's recorded in the
+      // set of clients that have registered the worker.
+      return activeClientIds.has(client.id)
+    })
+}
+
+async function getResponse(event, client, requestId) {
+  const { request } = event
+
+  // Clone the request because it might've been already used
+  // (i.e. its body has been read and sent to the client).
+  const requestClone = request.clone()
+
+  function passthrough() {
+    // Cast the request headers to a new Headers instance
+    // so the headers can be manipulated with.
+    const headers = new Headers(requestClone.headers)
+
+    // Remove the "accept" header value that marked this request as passthrough.
+    // This prevents request alteration and also keeps it compliant with the
+    // user-defined CORS policies.
+    headers.delete('accept', 'msw/passthrough')
+
+    return fetch(requestClone, { headers })
+  }
+
+  // Bypass mocking when the client is not active.
+  if (!client) {
+    return passthrough()
+  }
+
+  // Bypass initial page load requests (i.e. static assets).
+  // The absence of the immediate/parent client in the map of the active clients
+  // means that MSW hasn't dispatched the "MOCK_ACTIVATE" event yet
+  // and is not ready to handle requests.
+  if (!activeClientIds.has(client.id)) {
+    return passthrough()
+  }
+
+  // Notify the client that a request has been intercepted.
+  const requestBuffer = await request.arrayBuffer()
+  const clientMessage = await sendToClient(
+    client,
+    {
+      type: 'REQUEST',
+      payload: {
+        id: requestId,
+        url: request.url,
+        mode: request.mode,
+        method: request.method,
+        headers: Object.fromEntries(request.headers.entries()),
+        cache: request.cache,
+        credentials: request.credentials,
+        destination: request.destination,
+        integrity: request.integrity,
+        redirect: request.redirect,
+        referrer: request.referrer,
+        referrerPolicy: request.referrerPolicy,
+        body: requestBuffer,
+        keepalive: request.keepalive,
+      },
+    },
+    [requestBuffer],
+  )
+
+  switch (clientMessage.type) {
+    case 'MOCK_RESPONSE': {
+      return respondWithMock(clientMessage.data)
+    }
+
+    case 'PASSTHROUGH': {
+      return passthrough()
+    }
+  }
+
+  return passthrough()
+}
+
+function sendToClient(client, message, transferrables = []) {
+  return new Promise((resolve, reject) => {
+    const channel = new MessageChannel()
+
+    channel.port1.onmessage = (event) => {
+      if (event.data && event.data.error) {
+        return reject(event.data.error)
+      }
+
+      resolve(event.data)
+    }
+
+    client.postMessage(
+      message,
+      [channel.port2].concat(transferrables.filter(Boolean)),
+    )
+  })
+}
+
+async function respondWithMock(response) {
+  // Setting response status code to 0 is a no-op.
+  // However, when responding with a "Response.error()", the produced Response
+  // instance will have status code set to 0. Since it's not possible to create
+  // a Response instance with status code 0, handle that use-case separately.
+  if (response.status === 0) {
+    return Response.error()
+  }
+
+  const mockedResponse = new Response(response.body, response)
+
+  Reflect.defineProperty(mockedResponse, IS_MOCKED_RESPONSE, {
+    value: true,
+    enumerable: true,
+  })
+
+  return mockedResponse
+}

From 775f7bf98a7e566ab2b91b6cfb37e8e016ec8aba Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 29 Oct 2025 15:56:55 +0000
Subject: [PATCH 3/3] Add fallback to cached token when fetch fails

Co-authored-by: buckett <5921+buckett@users.noreply.github.com>
---
 .../tokenRetriever/LtiTokenRetriever.jsx      |  7 ++
 .../tokenRetriever/LtiTokenRetriever.test.jsx | 83 ++++++++++++++++++-
 2 files changed, 88 insertions(+), 2 deletions(-)

diff --git a/src/components/tokenRetriever/LtiTokenRetriever.jsx b/src/components/tokenRetriever/LtiTokenRetriever.jsx
index eb70931..8a76f74 100644
--- a/src/components/tokenRetriever/LtiTokenRetriever.jsx
+++ b/src/components/tokenRetriever/LtiTokenRetriever.jsx
@@ -64,6 +64,13 @@ export const LtiTokenRetriever = ({ ltiServer, handleJwt, children, location = w
         saveJwt(jwt);
         setState({ loading: false, error: null });
       } catch (error) {
+        // Try to get cached JWT before failing
+        const cachedJwt = loadJwt();
+        if (cachedJwt) {
+          handleJwt(cachedJwt, server);
+          setState({ loading: false, error: null });
+          return;
+        }
         setState({ loading: false, error: error.message });
       }
     };
diff --git a/src/components/tokenRetriever/LtiTokenRetriever.test.jsx b/src/components/tokenRetriever/LtiTokenRetriever.test.jsx
index aaf8a0f..c57792f 100644
--- a/src/components/tokenRetriever/LtiTokenRetriever.test.jsx
+++ b/src/components/tokenRetriever/LtiTokenRetriever.test.jsx
@@ -25,8 +25,16 @@ describe('LtiTokenRetriever Test Suite', () => {
     //  Close server after all tests
     afterAll(() => server.close())
 
+    // Clear sessionStorage before each test
+    beforeEach(() => {
+        sessionStorage.clear()
+        mockJwtFn.mockClear()
+    })
+
     // Reset handlers after each test `important for test isolation`
-    afterEach(() => server.resetHandlers())
+    afterEach(() => {
+        server.resetHandlers()
+    })
 
     it('Should show an error when no token', () => {
         render(
@@ -122,7 +130,78 @@ describe('LtiTokenRetriever Test Suite', () => {
         expect(await screen.findAllByText('Mock Child Element')).toBeDefined()
         expect(mockJwtFn).toHaveBeenCalledWith(jwt, mockServer)
     })
-    
+
+    it('Should use cached token when network error occurs and cached token exists', async () => {
+        const cachedJwt = 'cached.jwt.token'
+        const search = '?token=1234&other=something'
+        
+        // Pre-populate sessionStorage with a cached JWT
+        const tokenData = {
+            token: cachedJwt,
+            timestamp: Date.now()
+        }
+        sessionStorage.setItem('jwt', JSON.stringify(tokenData))
+        
+        vi.spyOn(window, 'location', 'get').mockReturnValue({search})
+        server.use(
+            http.post('http://server.test/token', async () => {
+                return HttpResponse.error()
+            })
+        )
+        render(
+            <LtiTokenRetriever handleJwt={mockJwtFn} ltiServer={mockServer}>
+                <h1>Mock Child Element</h1>
+            </LtiTokenRetriever>
+        )
+        
+        // Should succeed and use the cached token
+        expect(await screen.findAllByText('Mock Child Element')).toBeDefined()
+        expect(mockJwtFn).toHaveBeenCalledWith(cachedJwt, mockServer)
+    })
+
+    it('Should use cached token when server returns non-ok response and cached token exists', async () => {
+        const cachedJwt = 'cached.jwt.token'
+        const search = '?token=1234&other=something'
+        
+        // Pre-populate sessionStorage with a cached JWT
+        const tokenData = {
+            token: cachedJwt,
+            timestamp: Date.now()
+        }
+        sessionStorage.setItem('jwt', JSON.stringify(tokenData))
+        
+        vi.spyOn(window, 'location', 'get').mockReturnValue({search})
+        server.use(
+            http.post('http://server.test/token', async () => {
+                return HttpResponse.text('Not found', {status: 404})
+            })
+        )
+        render(
+            <LtiTokenRetriever handleJwt={mockJwtFn} ltiServer={mockServer}>
+                <h1>Mock Child Element</h1>
+            </LtiTokenRetriever>
+        )
+        
+        // Should succeed and use the cached token
+        expect(await screen.findAllByText('Mock Child Element')).toBeDefined()
+        expect(mockJwtFn).toHaveBeenCalledWith(cachedJwt, mockServer)
+    })
+
+    it('Should still show error when network error occurs and no cached token exists', async () => {
+        const search = '?token=1234&other=something'
+        vi.spyOn(window, 'location', 'get').mockReturnValue({search})
+        server.use(
+            http.post('http://server.test/token', async () => {
+                return HttpResponse.error()
+            })
+        )
+        render(
+            <LtiTokenRetriever handleJwt={mockJwtFn} ltiServer={mockServer}>
+                <h1>Mock Child Element</h1>
+            </LtiTokenRetriever>
+        )
+        expect(await screen.findByText('Failed to fetch')).toBeDefined()
+    })
 
 
 });
\ No newline at end of file