feat: Fetches chat history when loading Xpert

src/data/api.js

@@ -30,5 +30,15 @@ async function fetchLearningAssistantEnabled(courseId) {
   return data;
 }
 
-export default fetchChatResponse;
-export { fetchLearningAssistantEnabled };
+async function fetchLearningAssistantMessageHistory(courseId) {
+  const url = new URL(`${getConfig().CHAT_RESPONSE_URL}/${courseId}/history`);
+
+  const { data } = await getAuthenticatedHttpClient().get(url.href);
+  return data;
+}
+
+export {
+  fetchChatResponse,
+  fetchLearningAssistantEnabled,
+  fetchLearningAssistantMessageHistory,
+};

src/data/thunks.js

@@ -2,7 +2,7 @@ import { sendTrackEvent } from '@edx/frontend-platform/analytics';
 import { getAuthenticatedUser } from '@edx/frontend-platform/auth';
 
 import trackChatBotMessageOptimizely from '../utils/optimizelyExperiment';
-import fetchChatResponse, { fetchLearningAssistantEnabled } from './api';
+import { fetchChatResponse, fetchLearningAssistantMessageHistory, fetchLearningAssistantEnabled } from './api';
 import {
   setCurrentMessage,
   clearCurrentMessage,
@@ -81,6 +81,34 @@ export function clearMessages() {
   };
 }
 
+export function getLearningAssistantMessageHistory(courseId) {
+  return async (dispatch) => {
+    dispatch(resetApiError());
+    dispatch(setApiIsLoading(true));
+
+    try {
+      const rawMessageList = await fetchLearningAssistantMessageHistory(courseId);
+
+      if (rawMessageList.length) {
+        const messageList = rawMessageList
+          .map(({ timestamp, ...msg }) => ({
+            ...msg,
+            timestamp: new Date(timestamp), // Parse ISO time to Date()
+          }));
+
+        dispatch(setMessageList({ messageList }));
+
+        // If it has chat history, then we assume the user already aknowledged.
+        dispatch(setDisclosureAcknowledged(true));
+      }
+    } catch (e) {
+      dispatch(setApiError());
+    }
+
+    dispatch(setApiIsLoading(false));
+  };
+}
+
 export function updateCurrentMessage(content) {
   return (dispatch) => {
     dispatch(setCurrentMessage({ currentMessage: content }));

src/hooks/index.js

@@ -0,0 +1,2 @@
+/* eslint-disable import/prefer-default-export */
+export { useMessageHistory } from './message-history';

src/hooks/message-history.js

@@ -0,0 +1,15 @@
+/* eslint-disable import/prefer-default-export */
+import { useEffect } from 'react';
+import { useDispatch, useSelector } from 'react-redux';
+import { getLearningAssistantMessageHistory } from '../data/thunks';
+
+export const useMessageHistory = (courseId) => {
+  const dispatch = useDispatch();
+  const { isEnabled } = useSelector(state => state.learningAssistant);
+
+  useEffect(() => {
+    if (!courseId || !isEnabled) { return; }
+
+    dispatch(getLearningAssistantMessageHistory(courseId));
+  }, [dispatch, isEnabled, courseId]);
+};

src/widgets/Xpert.jsx

@@ -6,9 +6,11 @@ import { updateSidebarIsOpen, getIsEnabled } from '../data/thunks';
 import ToggleXpert from '../components/ToggleXpertButton';
 import Sidebar from '../components/Sidebar';
 import { ExperimentsProvider } from '../experiments';
+import { useMessageHistory } from '../hooks';
 
 const Xpert = ({ courseId, contentToolsEnabled, unitId }) => {
   const dispatch = useDispatch();
+  useMessageHistory(courseId);
 
   const {
     isEnabled,