feat: let users save cert project code to db (#44700)

* feat: let users save cert project code to db

fix: move getChallenges call out of request function so it only runs once

fix: use FlashMessages enum

fix: transform challengeFiles earlier

test: make tribute page use multifile editor

stuff I was playing with - revert this to get it to a working state

refactor: allow undefined editableRegionBoundaries

fix: save history

history is not necessarily ["name.ext"] and using the incorrect history
could cause weird bugs

fix: replace files -> challengeFiles on the client

refactor: DRY out ajax

fix: use file -> challengefile map

refactor: rename ajax types

fix: alphatize flash-messages.ts

revert: tribute page project

fix: remove logs

fix: prettier

fix: cypress

fix: prettier

fix: remove submitComplete action

fix: block UI for new projects

fix: handle code size

* fix: catch undefined files

* fix: don't default to undefined when it's already the default

* fix: only update savedChallenges if applicable

* fix: dehumidify backend + fine tune nearby stuff

* fix: prop-types

* fix: dehumidify sagas

* fix: variable name

* fix: types

* Apply suggestions from code review

Co-authored-by: Shaun Hamilton <shauhami020@gmail.com>

* fix: typo

* fix: prettier

* fix: props types

* fix: flash messages

* Update client/src/utils/challenge-request-helpers.ts

Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>

* chore: rename function uniformize -> standardize

* fix: flash message

* fix: add link to forum on flash messages

Co-authored-by: Shaun Hamilton <shauhami020@gmail.com>
Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>

api-server/src/common/models/user.js

@@ -994,6 +994,20 @@ export default function initializeUser(User) {
       return user.completedChallenges;
     });
   };
+  User.prototype.getSavedChallenges$ = function getSavedChallenges$() {
+    if (Array.isArray(this.savedChallenges) && this.savedChallenges.length) {
+      return Observable.of(this.savedChallenges);
+    }
+    const id = this.getId();
+    const filter = {
+      where: { id },
+      fields: { savedChallenges: true }
+    };
+    return this.constructor.findOne$(filter).map(user => {
+      this.savedChallenges = user.savedChallenges;
+      return user.savedChallenges;
+    });
+  };
 
   User.prototype.getPartiallyCompletedChallenges$ =
     function getPartiallyCompletedChallenges$() {

api-server/src/common/models/user.json

@@ -250,6 +250,39 @@
       ],
       "default": []
     },
+    "savedChallenges": {
+      "type": [
+        {
+          "lastSavedDate": "number",
+          "id": "string",
+          "challengeType": "number",
+          "files": {
+            "type": [
+              {
+                "contents": {
+                  "type": "string",
+                  "default": ""
+                },
+                "ext": {
+                  "type": "string"
+                },
+                "path": {
+                  "type": "string"
+                },
+                "name": {
+                  "type": "string"
+                },
+                "key": {
+                  "type": "string"
+                }
+              }
+            ],
+            "default": []
+          }
+        }
+      ],
+      "default": []
+    },
     "portfolio": {
       "type": "array",
       "default": []

api-server/src/common/utils/index.js

@@ -21,5 +21,8 @@ export const fixCompletedChallengeItem = obj =>
     'isManuallyApproved'
   ]);
 
+export const fixSavedChallengeItem = obj =>
+  pick(obj, ['id', 'lastSavedDate', 'files']);
+
 export const fixPartiallyCompletedChallengeItem = obj =>
   pick(obj, ['id', 'completedDate']);

api-server/src/server/boot/challenge.js

@@ -18,7 +18,8 @@ import { jwtSecret } from '../../../../config/secrets';
 import { environment, deploymentEnv } from '../../../../config/env.json';
 import {
   fixCompletedChallengeItem,
-  fixPartiallyCompletedChallengeItem
+  fixPartiallyCompletedChallengeItem,
+  fixSavedChallengeItem
 } from '../../common/utils';
 import { getChallenges } from '../utils/get-curriculum';
 import { ifNoUserSend } from '../utils/middleware';
@@ -64,6 +65,13 @@ export default async function bootChallenge(app, done) {
     backendChallengeCompleted
   );
 
+  api.post(
+    '/save-challenge',
+    send200toNonUser,
+    isValidChallengeCompletion,
+    saveChallenge
+  );
+
   router.get('/challenges/current-challenge', redirectToCurrentChallenge);
 
   const coderoadChallengeCompleted = createCoderoadChallengeCompleted(app);
@@ -87,6 +95,33 @@ const multiFileCertProjectIds = getChallenges()
   .filter(challenge => challenge.challengeType === 14)
   .map(challenge => challenge.id);
 
+const savableChallenges = getChallenges()
+  .filter(challenge => challenge.challengeType === 14)
+  .map(challenge => challenge.id);
+
+function buildNewSavedChallenges({
+  user,
+  challengeId,
+  completedDate = Date.now(),
+  files
+}) {
+  const { savedChallenges } = user;
+  const challengeToSave = {
+    id: challengeId,
+    lastSavedDate: completedDate,
+    files: files?.map(file =>
+      pick(file, ['contents', 'key', 'name', 'ext', 'history'])
+    )
+  };
+
+  const newSavedChallenges = uniqBy(
+    [challengeToSave, ...savedChallenges.map(fixSavedChallengeItem)],
+    'id'
+  );
+
+  return newSavedChallenges;
+}
+
 export function buildUserUpdate(
   user,
   challengeId,
@@ -101,7 +136,7 @@ export function buildUserUpdate(
   ) {
     completedChallenge = {
       ..._completedChallenge,
-      files: files.map(file =>
+      files: files?.map(file =>
         pick(file, ['contents', 'key', 'index', 'name', 'path', 'ext'])
       )
     };
@@ -133,13 +168,34 @@ export function buildUserUpdate(
     };
   }
 
-  updateData.$set = {
+  let newSavedChallenges;
-    completedChallenges: uniqBy(
-      [finalChallenge, ...completedChallenges.map(fixCompletedChallengeItem)],
-      'id'
-    )
-  };
 
+  if (savableChallenges.includes(challengeId)) {
+    newSavedChallenges = buildNewSavedChallenges({
+      user,
+      challengeId,
+      completedDate,
+      files
+    });
+
+    // if savableChallenge, update saved array when submitting
+    updateData.$set = {
+      completedChallenges: uniqBy(
+        [finalChallenge, ...completedChallenges.map(fixCompletedChallengeItem)],
+        'id'
+      ),
+      savedChallenges: newSavedChallenges
+    };
+  } else {
+    updateData.$set = {
+      completedChallenges: uniqBy(
+        [finalChallenge, ...completedChallenges.map(fixCompletedChallengeItem)],
+        'id'
+      )
+    };
+  }
+
+  // remove from partiallyCompleted on submit
   updateData.$pull = {
     partiallyCompletedChallenges: { id: challengeId }
   };
@@ -157,7 +213,8 @@ export function buildUserUpdate(
   return {
     alreadyCompleted,
     updateData,
-    completedDate: finalChallenge.completedDate
+    completedDate: finalChallenge.completedDate,
+    savedChallenges: newSavedChallenges
   };
 }
 
@@ -214,6 +271,7 @@ export function isValidChallengeCompletion(req, res, next) {
     body: { id, challengeType, solution }
   } = req;
 
+  // ToDO: Validate other things (challengeFiles, etc)
   const isValidChallengeCompletionErrorMsg = {
     type: 'error',
     message: 'That does not appear to be a valid challenge submission.'
@@ -248,6 +306,7 @@ export function modernChallengeCompleted(req, res, next) {
         completedDate
       };
 
+      // if multifile cert project
       if (challengeType === 14) {
         completedChallenge.isManuallyApproved = false;
       }
@@ -261,11 +320,12 @@ export function modernChallengeCompleted(req, res, next) {
         completedChallenge.challengeType = challengeType;
       }
 
-      const { alreadyCompleted, updateData } = buildUserUpdate(
+      const { alreadyCompleted, savedChallenges, updateData } = buildUserUpdate(
         user,
         id,
         completedChallenge
       );
+
       const points = alreadyCompleted ? user.points : user.points + 1;
       const updatePromise = new Promise((resolve, reject) =>
         user.updateAttributes(updateData, err => {
@@ -279,7 +339,8 @@ export function modernChallengeCompleted(req, res, next) {
         return res.json({
           points,
           alreadyCompleted,
-          completedDate
+          completedDate,
+          savedChallenges
         });
       });
     })
@@ -389,6 +450,45 @@ function backendChallengeCompleted(req, res, next) {
     .subscribe(() => {}, next);
 }
 
+function saveChallenge(req, res, next) {
+  const user = req.user;
+  const { id: challengeId, files = [] } = req.body;
+
+  if (!savableChallenges.includes(challengeId)) {
+    return res.status(403).send('That challenge type is not savable');
+  }
+
+  const newSavedChallenges = buildNewSavedChallenges({
+    user,
+    challengeId,
+    completedDate: Date.now(),
+    files
+  });
+
+  return user
+    .getSavedChallenges$()
+    .flatMap(() => {
+      const updateData = {};
+      updateData.$set = {
+        savedChallenges: newSavedChallenges
+      };
+      const updatePromise = new Promise((resolve, reject) =>
+        user.updateAttributes(updateData, err => {
+          if (err) {
+            return reject(err);
+          }
+          return resolve();
+        })
+      );
+      return Observable.fromPromise(updatePromise).doOnNext(() => {
+        return res.json({
+          savedChallenges: newSavedChallenges
+        });
+      });
+    })
+    .subscribe(() => {}, next);
+}
+
 const codeRoadChallenges = getChallenges().filter(
   ({ challengeType }) => challengeType === 12 || challengeType === 13
 );

api-server/src/server/boot/user.js

@@ -6,7 +6,8 @@ import { Observable } from 'rx';
 
 import {
   fixCompletedChallengeItem,
-  fixPartiallyCompletedChallengeItem
+  fixPartiallyCompletedChallengeItem,
+  fixSavedChallengeItem
 } from '../../common/utils';
 import { removeCookies } from '../utils/getSetAccessToken';
 import { ifNoUser401, ifNoUserRedirectHome } from '../utils/middleware';
@@ -114,18 +115,21 @@ function createReadSessionUser(app) {
       Observable.forkJoin(
         queryUser.getCompletedChallenges$(),
         queryUser.getPartiallyCompletedChallenges$(),
+        queryUser.getSavedChallenges$(),
         queryUser.getPoints$(),
         Donation.getCurrentActiveDonationCount$(),
         (
           completedChallenges,
           partiallyCompletedChallenges,
+          savedChallenges,
           progressTimestamps,
           activeDonations
         ) => ({
           activeDonations,
           completedChallenges,
           partiallyCompletedChallenges,
-          progress: getProgress(progressTimestamps, queryUser.timezone)
+          progress: getProgress(progressTimestamps, queryUser.timezone),
+          savedChallenges
         })
       );
     Observable.if(
@@ -137,7 +141,8 @@ function createReadSessionUser(app) {
             activeDonations,
             completedChallenges,
             partiallyCompletedChallenges,
-            progress
+            progress,
+            savedChallenges
           }) => ({
             user: {
               ...queryUser.toJSON(),
@@ -147,7 +152,8 @@ function createReadSessionUser(app) {
               ),
               partiallyCompletedChallenges: partiallyCompletedChallenges.map(
                 fixPartiallyCompletedChallengeItem
-              )
+              ),
+              savedChallenges: savedChallenges.map(fixSavedChallengeItem)
             },
             sessionMeta: { activeDonations }
           })

api-server/src/server/middlewares/error-handlers.js

@@ -26,6 +26,11 @@ export default function prodErrorHandler() {
   // error handling in production.
   // eslint-disable-next-line no-unused-vars
   return function (err, req, res, next) {
+    // response for when req.body is bigger than body-parser's size limit
+    if (err?.type === 'entity.too.large') {
+      return res.status('413').send('Request payload is too large');
+    }
+
     const { origin } = getRedirectParams(req);
     const handled = unwrapHandledError(err);
     // respect handled error status

api-server/src/server/utils/publicUserProps.js

@@ -38,6 +38,7 @@ export const publicUserProps = [
   'portfolio',
   'profileUI',
   'projects',
+  'savedChallenges',
   'streak',
   'twitter',
   'username',

client/i18n/locales/english/translations.json

@@ -58,6 +58,7 @@
     "resubscribe": "You can click here to resubscribe",
     "click-here": "Click here to sign in",
     "save": "Save",
+    "save-code": "Save your Code",
     "no-thanks": "No thanks",
     "yes-please": "Yes please",
     "update-email": "Update my Email",
@@ -529,7 +530,11 @@
     "start-project-err": "Something went wrong trying to start the project. Please try again.",
     "complete-project-first": "You must complete the project first.",
     "local-code-save-error": "Oops, your code did not save, your browser's local storage may be full.",
-    "local-code-saved": "Saved! Your code was saved to your browser's local storage."
+    "local-code-saved": "Saved! Your code was saved to your browser's local storage.",
+    "code-saved": "Your code was saved to the database. It will be here when you return.",
+    "code-save-error": "An error occurred trying to save your code.",
+    "challenge-save-too-big": "Sorry, you cannot save your code. Your code is {{user-size}} bytes. We allow a maximum of {{max-size}} bytes. Please make your code smaller and try again or request assistance on https://forum.freecodecamp.org",
+    "challenge-submit-too-big": "Sorry, you cannot submit your code. Your code is {{user-size}} bytes. We allow a maximum of {{max-size}} bytes. Please make your code smaller and try again or request assistance on https://forum.freecodecamp.org"
   },
   "validation": {
     "max-characters": "There is a maximum limit of 288 characters, you have {{charsLeft}} left",

client/src/components/Flash/redux/flash-messages.ts

@@ -5,6 +5,10 @@ export enum FlashMessages {
   CertClaimSuccess = 'flash.cert-claim-success',
   CertificateMissing = 'flash.certificate-missing',
   CertsPrivate = 'flash.certs-private',
+  ChallengeSaveTooBig = 'flash.challenge-save-too-big',
+  ChallengeSubmitTooBig = 'flash.challenge-submit-too-big',
+  CodeSaved = 'flash.code-saved',
+  CodeSaveError = 'flash.code-save-error',
   CompleteProjectFirst = 'flash.complete-project-first',
   DeleteTokenErr = 'flash.delete-token-err',
   EmailValid = 'flash.email-valid',

client/src/components/layouts/default.tsx

@@ -209,7 +209,7 @@ class DefaultLayout extends Component<DefaultLayoutProps> {
               removeFlashMessage={removeFlashMessage}
             />
           ) : null}
-          {children}
+          {fetchState.complete && children}
         </div>
         {showFooter && <Footer />}
       </div>

client/src/components/profile/profile.test.tsx

@@ -47,6 +47,7 @@ const userProps = {
     name: 'string',
     picture: 'string',
     points: 1,
+    savedChallenges: [],
     sendQuincyEmail: true,
     sound: true,
     theme: Themes.Default,

client/src/redux/action-types.js

@@ -34,7 +34,8 @@ export const actionTypes = createTypes(
     ...createAsyncTypes('showCert'),
     ...createAsyncTypes('reportUser'),
     ...createAsyncTypes('postChargeStripeCard'),
-    ...createAsyncTypes('deleteUserToken')
+    ...createAsyncTypes('deleteUserToken'),
+    ...createAsyncTypes('saveChallenge')
   ],
   ns
 );

client/src/redux/index.js

@@ -22,6 +22,7 @@ import { createShowCertSaga } from './show-cert-saga';
 import { createSoundModeSaga } from './sound-mode-saga';
 import updateCompleteEpic from './update-complete-epic';
 import { createUserTokenSaga } from './user-token-saga';
+import { createSaveChallengeSaga } from './save-challenge-saga';
 
 export const MainApp = 'app';
 
@@ -82,7 +83,8 @@ export const sagas = [
   ...createShowCertSaga(actionTypes),
   ...createReportUserSaga(actionTypes),
   ...createSoundModeSaga({ ...actionTypes, ...settingsTypes }),
-  ...createUserTokenSaga(actionTypes)
+  ...createUserTokenSaga(actionTypes),
+  ...createSaveChallengeSaga(actionTypes)
 ];
 
 export const appMount = createAction(actionTypes.appMount);
@@ -121,6 +123,11 @@ export const submitComplete = createAction(actionTypes.submitComplete);
 export const updateComplete = createAction(actionTypes.updateComplete);
 export const updateFailed = createAction(actionTypes.updateFailed);
 
+export const saveChallenge = createAction(actionTypes.saveChallenge);
+export const saveChallengeComplete = createAction(
+  actionTypes.saveChallengeComplete
+);
+
 export const acceptTerms = createAction(actionTypes.acceptTerms);
 export const acceptTermsComplete = createAction(
   actionTypes.acceptTermsComplete
@@ -188,6 +195,8 @@ export const updateCurrentChallengeId = createAction(
   actionTypes.updateCurrentChallengeId
 );
 
+export const savedChallengesSelector = state =>
+  userSelector(state).savedChallenges || [];
 export const completedChallengesSelector = state =>
   userSelector(state).completedChallenges || [];
 export const partiallyCompletedChallengesSelector = state =>
@@ -637,9 +646,12 @@ export const reducer = handleActions(
       }
     }),
     [actionTypes.submitComplete]: (state, { payload }) => {
-      let submittedchallenges = [{ ...payload, completedDate: Date.now() }];
+      const { submittedChallenge, savedChallenges } = payload;
-      if (payload.challArray) {
+      let submittedchallenges = [
-        submittedchallenges = payload.challArray;
+        { ...submittedChallenge, completedDate: Date.now() }
+      ];
+      if (submittedChallenge.challArray) {
+        submittedchallenges = submittedChallenge.challArray;
       }
       const { appUsername } = state;
       return {
@@ -655,7 +667,9 @@ export const reducer = handleActions(
                 ...state.user[appUsername].completedChallenges
               ],
               'id'
-            )
+            ),
+            savedChallenges:
+              savedChallenges ?? savedChallengesSelector(state[MainApp])
           }
         }
       };
@@ -702,6 +716,19 @@ export const reducer = handleActions(
       ...state,
       currentChallengeId: payload
     }),
+    [actionTypes.saveChallengeComplete]: (state, { payload }) => {
+      const { appUsername } = state;
+      return {
+        ...state,
+        user: {
+          ...state.user,
+          [appUsername]: {
+            ...state.user[appUsername],
+            savedChallenges: payload
+          }
+        }
+      };
+    },
     [settingsTypes.submitNewUsernameComplete]: (state, { payload }) =>
       payload
         ? {

client/src/redux/prop-types.ts

@@ -50,6 +50,12 @@ export const UserPropType = PropTypes.shape({
       description: PropTypes.string
     })
   ),
+  savedChallenges: PropTypes.arrayOf(
+    PropTypes.shape({
+      id: PropTypes.string,
+      challengeFiles: PropTypes.array
+    })
+  ),
   sendQuincyEmail: PropTypes.bool,
   sound: PropTypes.bool,
   theme: PropTypes.string,
@@ -267,6 +273,7 @@ export type User = {
   portfolio: Portfolio[];
   profileUI: ProfileUI;
   progressTimestamps: Array<unknown>;
+  savedChallenges: SavedChallenges;
   sendQuincyEmail: boolean;
   sound: boolean;
   theme: Themes;
@@ -310,6 +317,23 @@ export type ClaimedCertifications = {
   isMachineLearningPyCertV7: boolean;
 };
 
+export type SavedChallenges = SavedChallenge[];
+
+export type SavedChallenge = {
+  id: string;
+  challengeFiles: SavedChallengeFiles;
+};
+
+export type SavedChallengeFile = {
+  fileKey: string;
+  ext: Ext;
+  name: string;
+  history?: string[];
+  contents: string;
+};
+
+export type SavedChallengeFiles = SavedChallengeFile[];
+
 export type CompletedChallenge = {
   id: string;
   solution?: string | null;
@@ -359,8 +383,8 @@ export type ChallengeFile = {
   fileKey: string;
   ext: Ext;
   name: string;
-  editableRegionBoundaries: number[];
+  editableRegionBoundaries?: number[];
-  usesMultifileEditor: boolean;
+  usesMultifileEditor?: boolean;
   error: null | string;
   head: string;
   tail: string;

client/src/redux/save-challenge-saga.js

@@ -0,0 +1,68 @@
+import { call, takeEvery, put, select } from 'redux-saga/effects';
+import { postSaveChallenge, mapFilesToChallengeFiles } from '../utils/ajax';
+import {
+  challengeDataSelector,
+  challengeMetaSelector
+} from '../templates/Challenges/redux';
+import { createFlashMessage } from '../components/Flash/redux';
+import { challengeTypes } from '../../utils/challenge-types';
+import { FlashMessages } from '../components/Flash/redux/flash-messages';
+import {
+  standardizeRequestBody,
+  getStringSizeInBytes,
+  bodySizeFits,
+  MAX_BODY_SIZE
+} from '../utils/challenge-request-helpers';
+import { saveChallengeComplete } from './';
+
+export function* saveChallengeSaga() {
+  const { id, challengeType } = yield select(challengeMetaSelector);
+  const { challengeFiles } = yield select(challengeDataSelector);
+
+  // only allow saving of multiFileCertProject's
+  if (challengeType === challengeTypes.multiFileCertProject) {
+    const body = standardizeRequestBody({ id, challengeFiles, challengeType });
+    const bodySizeInBytes = getStringSizeInBytes(body);
+
+    if (!bodySizeFits(bodySizeInBytes)) {
+      return yield put(
+        createFlashMessage({
+          type: 'danger',
+          message: FlashMessages.ChallengeSaveTooBig,
+          variables: { 'max-size': MAX_BODY_SIZE, 'user-size': bodySizeInBytes }
+        })
+      );
+    } else {
+      try {
+        const response = yield call(postSaveChallenge, body);
+
+        if (response?.message) {
+          yield put(createFlashMessage(response));
+        } else if (response?.savedChallenges) {
+          yield put(
+            saveChallengeComplete(
+              mapFilesToChallengeFiles(response.savedChallenges)
+            )
+          );
+          yield put(
+            createFlashMessage({
+              type: 'success',
+              message: FlashMessages.CodeSaved
+            })
+          );
+        }
+      } catch (e) {
+        yield put(
+          createFlashMessage({
+            type: 'danger',
+            message: FlashMessages.CodeSaveError
+          })
+        );
+      }
+    }
+  }
+}
+
+export function createSaveChallengeSaga(types) {
+  return [takeEvery(types.saveChallenge, saveChallengeSaga)];
+}

client/src/templates/Challenges/classic/action-row.tsx

@@ -8,6 +8,7 @@ import EditorTabs from './editor-tabs';
 interface ActionRowProps {
   block: string;
   hasNotes: boolean;
+  isMultiFileCertProject: boolean;
   showConsole: boolean;
   showNotes: boolean;
   showPreview: boolean;
@@ -22,6 +23,7 @@ const mapDispatchToProps = {
 
 const ActionRow = ({
   hasNotes,
+  isMultiFileCertProject,
   togglePane,
   showNotes,
   showPreview,
@@ -38,9 +40,11 @@ const ActionRow = ({
       </div>
       <div className='tabs-row'>
         <EditorTabs />
-        <button className='restart-step-tab' onClick={resetChallenge}>
+        {!isMultiFileCertProject && (
-          {t('learn.editor-tabs.restart-step')}
+          <button className='restart-step-tab' onClick={resetChallenge}>
-        </button>
+            {t('learn.editor-tabs.restart-step')}
+          </button>
+        )}
         <div className='panel-display-tabs'>
           <button
             aria-expanded={showConsole ? 'true' : 'false'}

client/src/templates/Challenges/classic/desktop-layout.tsx

@@ -110,6 +110,7 @@ const DesktopLayout = (props: DesktopLayoutProps): JSX.Element => {
         <ActionRow
           block={block}
           hasNotes={hasNotes}
+          isMultiFileCertProject={isMultiFileCertProject}
           showConsole={showConsole}
           showNotes={showNotes}
           showPreview={showPreview}

client/src/templates/Challenges/classic/editor.tsx

@@ -82,7 +82,7 @@ interface EditorProps {
   updateFile: (object: {
     fileKey: FileKey;
     editorValue: string;
-    editableRegionBoundaries: number[] | null;
+    editableRegionBoundaries?: number[];
   }) => void;
   usesMultifileEditor: boolean;
 }
@@ -632,10 +632,12 @@ const Editor = (props: EditorProps): JSX.Element => {
     // has changed or if content is dragged between regions)
 
     const coveringRange = getLinesCoveringEditableRegion();
-    const editableRegionBoundaries = coveringRange && [
+    const editableRegionBoundaries =
-      coveringRange.startLineNumber - 1,
+      (coveringRange && [
-      coveringRange.endLineNumber + 1
+        coveringRange.startLineNumber - 1,
-    ];
+        coveringRange.endLineNumber + 1
+      ]) ??
+      undefined;
 
     // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
     if (player.current.sampler?.loaded && player.current.shouldPlay) {

client/src/templates/Challenges/classic/show.tsx

@@ -12,12 +12,12 @@ import { challengeTypes } from '../../../../utils/challenge-types';
 import LearnLayout from '../../../components/layouts/learn';
 
 import {
-  ChallengeFile,
   ChallengeFiles,
   ChallengeMeta,
   ChallengeNode,
   CompletedChallenge,
   ResizeProps,
+  SavedChallengeFiles,
   Test
 } from '../../../redux/prop-types';
 import { isContained } from '../../../utils/is-contained';
@@ -49,6 +49,7 @@ import {
   openModal,
   setEditorFocusability
 } from '../redux';
+import { savedChallengesSelector } from '../../../redux';
 import { getGuideUrl } from '../utils';
 import MultifileEditor from './MultifileEditor';
 import DesktopLayout from './desktop-layout';
@@ -62,7 +63,8 @@ const mapStateToProps = createStructuredSelector({
   challengeFiles: challengeFilesSelector,
   tests: challengeTestsSelector,
   output: consoleOutputSelector,
-  isChallengeCompleted: isChallengeCompletedSelector
+  isChallengeCompleted: isChallengeCompletedSelector,
+  savedChallenges: savedChallengesSelector
 });
 
 const mapDispatchToProps = (dispatch: Dispatch) =>
@@ -86,7 +88,7 @@ const mapDispatchToProps = (dispatch: Dispatch) =>
 interface ShowClassicProps {
   cancelTests: () => void;
   challengeMounted: (arg0: string) => void;
-  createFiles: (arg0: ChallengeFile[]) => void;
+  createFiles: (arg0: ChallengeFiles | SavedChallengeFiles) => void;
   data: { challengeNode: ChallengeNode };
   executeChallenge: (options?: { showCompletionModal: boolean }) => void;
   challengeFiles: ChallengeFiles;
@@ -107,6 +109,7 @@ interface ShowClassicProps {
   openModal: (modal: string) => void;
   setEditorFocusability: (canFocus: boolean) => void;
   previewMounted: () => void;
+  savedChallenges: CompletedChallenge[];
 }
 
 interface ShowClassicState {
@@ -256,6 +259,7 @@ class ShowClassic extends Component<ShowClassicProps, ShowClassicState> {
       initTests,
       updateChallengeMeta,
       openModal,
+      savedChallenges,
       data: {
         challengeNode: {
           challenge: {
@@ -273,7 +277,13 @@ class ShowClassic extends Component<ShowClassicProps, ShowClassicState> {
       }
     } = this.props;
     initConsole('');
-    createFiles(challengeFiles ?? []);
+
+    const savedChallenge = savedChallenges?.find(challenge => {
+      return challenge.id === challengeMeta.id;
+    });
+
+    createFiles(savedChallenge?.challengeFiles || challengeFiles || []);
+
     initTests(tests);
     if (showProjectPreview) openModal('projectPreview');
     updateChallengeMeta({
@@ -521,6 +531,7 @@ export const query = graphql`
         block
         title
         description
+        id
         hasEditableBoundaries
         instructions
         notes

client/src/templates/Challenges/components/tool-panel.tsx

@@ -7,25 +7,43 @@ import React from 'react';
 import { useTranslation } from 'react-i18next';
 import { connect } from 'react-redux';
 import { bindActionCreators, Dispatch } from 'redux';
+import { createSelector } from 'reselect';
+import { challengeTypes } from '../../../../utils/challenge-types';
 
 import './tool-panel.css';
-import { openModal, executeChallenge } from '../redux';
+import { openModal, executeChallenge, challengeMetaSelector } from '../redux';
 
-const mapStateToProps = () => ({});
+import { saveChallenge, isSignedInSelector } from '../../../redux';
+
+const mapStateToProps = createSelector(
+  challengeMetaSelector,
+  isSignedInSelector,
+  (
+    { challengeType }: { challengeId: string; challengeType: number },
+    isSignedIn
+  ) => ({
+    challengeType,
+    isSignedIn
+  })
+);
 const mapDispatchToProps = (dispatch: Dispatch) =>
   bindActionCreators(
     {
       executeChallenge,
       openHelpModal: () => openModal('help'),
       openVideoModal: () => openModal('video'),
-      openResetModal: () => openModal('reset')
+      openResetModal: () => openModal('reset'),
+      saveChallenge
     },
     dispatch
   );
 
 interface ToolPanelProps {
+  challengeType: number;
   executeChallenge: (options?: { showCompletionModal: boolean }) => void;
+  saveChallenge: () => void;
   isMobile?: boolean;
+  isSignedIn: boolean;
   openHelpModal: () => void;
   openVideoModal: () => void;
   openResetModal: () => void;
@@ -34,8 +52,11 @@ interface ToolPanelProps {
 }
 
 function ToolPanel({
+  challengeType,
   executeChallenge,
+  saveChallenge,
   isMobile,
+  isSignedIn,
   openHelpModal,
   openVideoModal,
   openResetModal,
@@ -60,14 +81,26 @@ function ToolPanel({
       >
         {isMobile ? t('buttons.run') : t('buttons.run-test')}
       </Button>
-      <Button
+      {isSignedIn && challengeType === challengeTypes.multiFileCertProject && (
-        block={true}
+        <Button
-        bsStyle='primary'
+          block={true}
-        className='btn-invert'
+          bsStyle='primary'
-        onClick={openResetModal}
+          className='btn-invert'
-      >
+          onClick={saveChallenge}
-        {isMobile ? t('buttons.reset') : t('buttons.reset-code')}
+        >
-      </Button>
+          {isMobile ? t('buttons.save') : t('buttons.save-code')}
+        </Button>
+      )}
+      {challengeType !== challengeTypes.multiFileCertProject && (
+        <Button
+          block={true}
+          bsStyle='primary'
+          className='btn-invert'
+          onClick={openResetModal}
+        >
+          {isMobile ? t('buttons.reset') : t('buttons.reset-code')}
+        </Button>
+      )}
       <DropdownButton
         block={true}
         bsStyle='primary'

client/src/templates/Challenges/redux/completion-epic.js

@@ -21,6 +21,8 @@ import {
 } from '../../../redux';
 
 import postUpdate$ from '../utils/postUpdate$';
+import { mapFilesToChallengeFiles } from '../../../utils/ajax';
+import { standardizeRequestBody } from '../../../utils/challenge-request-helpers';
 import { actionTypes } from './action-types';
 import {
   projectFormValuesSelector,
@@ -34,7 +36,7 @@ import {
 function postChallenge(update, username) {
   const saveChallenge = postUpdate$(update).pipe(
     retry(3),
-    switchMap(({ points }) => {
+    switchMap(({ points, savedChallenges }) => {
       // TODO: do this all in ajax.ts
       const payloadWithClientProperties = {
         ...omit(update.payload, ['files'])
@@ -49,9 +51,12 @@ function postChallenge(update, username) {
       }
       return of(
         submitComplete({
-          username,
+          submittedChallenge: {
-          points,
+            username,
-          ...payloadWithClientProperties
+            points,
+            ...payloadWithClientProperties
+          },
+          savedChallenges: mapFilesToChallengeFiles(savedChallenges)
         }),
         updateComplete()
       );
@@ -76,24 +81,23 @@ function submitModern(type, state) {
       const { id, block } = challengeMetaSelector(state);
       const challengeFiles = challengeFilesSelector(state);
       const { username } = userSelector(state);
-      const challengeInfo = {
-        id,
-        challengeType
-      };
 
-      // Only send files to server, if it is a JS project or multiFile cert project
+      let body;
       if (
         block === 'javascript-algorithms-and-data-structures-projects' ||
         challengeType === challengeTypes.multiFileCertProject
       ) {
-        challengeInfo.files = challengeFiles.reduce(
+        body = standardizeRequestBody({ id, challengeType, challengeFiles });
-          (acc, { fileKey, ...curr }) => [...acc, { ...curr, key: fileKey }],
+      } else {
-          []
+        body = {
-        );
+          id,
+          challengeType
+        };
       }
+
       const update = {
         endpoint: '/modern-challenge-completed',
-        payload: challengeInfo
+        payload: body
       };
       return postChallenge(update, username);
     }

client/src/templates/Challenges/redux/execute-challenge-saga.js

@@ -25,6 +25,15 @@ import {
   isJavaScriptChallenge,
   isLoopProtected
 } from '../utils/build';
+import { challengeTypes } from '../../../../utils/challenge-types';
+import { createFlashMessage } from '../../../components/Flash/redux';
+import { FlashMessages } from '../../../components/Flash/redux/flash-messages';
+import {
+  standardizeRequestBody,
+  getStringSizeInBytes,
+  bodySizeFits,
+  MAX_BODY_SIZE
+} from '../../../utils/challenge-request-helpers';
 import { actionTypes } from './action-types';
 import {
   challengeDataSelector,
@@ -45,7 +54,27 @@ import {
 const previewTimeout = 2500;
 let previewTask;
 
+// when 'run tests' is clicked, do this first
 export function* executeCancellableChallengeSaga(payload) {
+  const { challengeType, id } = yield select(challengeMetaSelector);
+  const { challengeFiles } = yield select(challengeDataSelector);
+
+  // if multiFileCertProject, see if body/code size is submittable
+  if (challengeType === challengeTypes.multiFileCertProject) {
+    const body = standardizeRequestBody({ id, challengeFiles, challengeType });
+    const bodySizeInBytes = getStringSizeInBytes(body);
+
+    if (!bodySizeFits(bodySizeInBytes)) {
+      return yield put(
+        createFlashMessage({
+          type: 'danger',
+          message: FlashMessages.ChallengeSubmitTooBig,
+          variables: { 'max-size': MAX_BODY_SIZE, 'user-size': bodySizeInBytes }
+        })
+      );
+    }
+  }
+
   if (previewTask) {
     yield cancel(previewTask);
   }

client/src/templates/Challenges/redux/index.js

@@ -68,7 +68,7 @@ export const createFiles = createAction(
         challengeFile.editableRegionBoundaries
       ),
       seedEditableRegionBoundaries:
-        challengeFile.editableRegionBoundaries.slice()
+        challengeFile.editableRegionBoundaries?.slice()
     }))
 );
 

client/src/templates/Challenges/utils/build.js

@@ -149,16 +149,19 @@ export function buildDOMChallenge(
   const finalFiles = challengeFiles.map(pipeLine);
   return Promise.all(finalFiles)
     .then(checkFilesErrors)
-    .then(challengeFiles => ({
+    .then(challengeFiles => {
-      challengeType: challengeTypes.html,
+      return {
-      build: concatHtml({
+        challengeType:
-        required: finalRequires,
+          challengeTypes.html || challengeTypes.multiFileCertProject,
-        template,
+        build: concatHtml({
-        challengeFiles
+          required: finalRequires,
-      }),
+          template,
-      sources: buildSourceMap(challengeFiles),
+          challengeFiles
-      loadEnzyme
+        }),
-    }));
+        sources: buildSourceMap(challengeFiles),
+        loadEnzyme
+      };
+    });
 }
 
 export function buildJSChallenge({ challengeFiles }, options) {

client/src/templates/Introduction/components/block.tsx

@@ -127,7 +127,8 @@ export class Block extends Component<BlockProps> {
         challenge.challengeType === 4 ||
         challenge.challengeType === 10 ||
         challenge.challengeType === 12 ||
-        challenge.challengeType === 13;
+        challenge.challengeType === 13 ||
+        challenge.challengeType === 14;
 
       const isTakeHomeProject = blockDashedName === 'take-home-projects';
 

client/src/utils/ajax.ts

@@ -3,7 +3,10 @@ import envData from '../../../config/env.json';
 
 import type {
   ChallengeFile,
+  ChallengeFiles,
   CompletedChallenge,
+  SavedChallenge,
+  SavedChallengeFile,
   User
 } from '../redux/prop-types';
 
@@ -65,15 +68,23 @@ interface SessionUser {
   sessionMeta: { activeDonations: number };
 }
 
-type ChallengeFilesForFiles = {
+type CompleteChallengeFromApi = {
   files: Array<Omit<ChallengeFile, 'fileKey'> & { key: string }>;
 } & Omit<CompletedChallenge, 'challengeFiles'>;
 
+type SavedChallengeFromApi = {
+  files: Array<Omit<SavedChallengeFile, 'fileKey'> & { key: string }>;
+} & Omit<SavedChallenge, 'challengeFiles'>;
+
 type ApiSessionResponse = Omit<SessionUser, 'user'>;
 type ApiUser = {
   user: {
-    [username: string]: Omit<User, 'completedChallenges'> & {
+    [username: string]: Omit<
-      completedChallenges?: ChallengeFilesForFiles[];
+      User,
+      'completedChallenges' & 'savedChallenges'
+    > & {
+      completedChallenges?: CompleteChallengeFromApi[];
+      savedChallenges?: SavedChallengeFromApi[];
     };
   };
   result?: string;
@@ -87,30 +98,36 @@ type UserResponse = {
 function parseApiResponseToClientUser(data: ApiUser): UserResponse {
   const userData = data.user?.[data?.result ?? ''];
   let completedChallenges: CompletedChallenge[] = [];
+  let savedChallenges: SavedChallenge[] = [];
   if (userData) {
-    completedChallenges =
+    completedChallenges = mapFilesToChallengeFiles(
-      userData.completedChallenges?.reduce(
+      userData.completedChallenges
-        (acc: CompletedChallenge[], curr: ChallengeFilesForFiles) => {
+    );
-          return [
+    savedChallenges = mapFilesToChallengeFiles(userData.savedChallenges);
-            ...acc,
-            {
-              ...curr,
-              challengeFiles: curr.files.map(({ key: fileKey, ...file }) => ({
-                ...file,
-                fileKey
-              }))
-            }
-          ];
-        },
-        []
-      ) ?? [];
   }
   return {
-    user: { [data.result ?? '']: { ...userData, completedChallenges } },
+    user: {
+      [data.result ?? '']: { ...userData, completedChallenges, savedChallenges }
+    },
     result: data.result
   };
 }
 
+export function mapFilesToChallengeFiles<File, Rest>(
+  fileContainer: ({ files: (File & { key: string })[] } & Rest)[] = []
+) {
+  return fileContainer.map(({ files, ...rest }) => ({
+    ...rest,
+    challengeFiles: mapKeyToFileKey(files)
+  }));
+}
+
+function mapKeyToFileKey<K>(
+  files: (K & { key: string })[]
+): (Omit<K, 'key'> & { fileKey: string })[] {
+  return files.map(({ key, ...rest }) => ({ ...rest, fileKey: key }));
+}
+
 export function getSessionUser(): Promise<SessionUser> {
   const response: Promise<ApiUser & ApiSessionResponse> = get(
     '/user/get-session-user'
@@ -207,6 +224,13 @@ export function postUserToken(): Promise<void> {
   return post('/user/user-token', {});
 }
 
+export function postSaveChallenge(body: {
+  id: string;
+  files: ChallengeFiles;
+}): Promise<void> {
+  return post('/save-challenge', body);
+}
+
 /** PUT **/
 
 interface MyAbout {

client/src/utils/challenge-request-helpers.ts

@@ -0,0 +1,44 @@
+import { ChallengeFiles } from '../redux/prop-types';
+
+/*
+ * Express's body-parser has a default size limit of 102400 bytes for a request body.
+ * These helper functions make sure the request body isn't too big when saving or submitting multiFile cert projects
+ */
+
+export const MAX_BODY_SIZE = 102400;
+
+interface StandardizeRequestBodyArgs {
+  id: string;
+  challengeFiles: ChallengeFiles;
+  challengeType: number;
+}
+
+export function standardizeRequestBody({
+  id,
+  challengeFiles = [],
+  challengeType
+}: StandardizeRequestBodyArgs) {
+  return {
+    id,
+    files: challengeFiles?.map(({ fileKey, contents, ext, name, history }) => {
+      return {
+        contents,
+        ext,
+        history,
+        key: fileKey,
+        name
+      };
+    }),
+    challengeType
+  };
+}
+
+export function getStringSizeInBytes(str = '') {
+  const stringSizeInBytes = new Blob([JSON.stringify(str)]).size;
+
+  return stringSizeInBytes;
+}
+
+export function bodySizeFits(bodySizeInBytes: number) {
+  return bodySizeInBytes <= MAX_BODY_SIZE;
+}

client/src/utils/tone/index.ts

@@ -20,6 +20,10 @@ const toneUrls = {
     'https://campfire-mode.freecodecamp.org/cert.mp3',
   [FlashMessages.CertificateMissing]: TRY_AGAIN,
   [FlashMessages.CertsPrivate]: TRY_AGAIN,
+  [FlashMessages.ChallengeSaveTooBig]: TRY_AGAIN,
+  [FlashMessages.ChallengeSubmitTooBig]: TRY_AGAIN,
+  [FlashMessages.CodeSaved]: CHAL_COMP,
+  [FlashMessages.CodeSaveError]: TRY_AGAIN,
   [FlashMessages.CompleteProjectFirst]: TRY_AGAIN,
   [FlashMessages.DeleteTokenErr]: TRY_AGAIN,
   [FlashMessages.EmailValid]: CHAL_COMP,

cypress/integration/learn/responsive-web-design/intro-page.js

@@ -4,6 +4,7 @@ const selectors = {
 
 describe('Certification intro page', () => {
   before(() => {
+    cy.exec('npm run seed');
     cy.clearCookies();
     cy.login();
     cy.visit('/learn/responsive-web-design');