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Question sets

  1. 1
    Whats ORM (I did raw sql i was honest abt it i told ppl said u can go with either aproach he said ok)
    Times asked 2
    Official solution

    SimpleORM = Object Relational Mapping. Tables → Python classes. Raw SQL kam likhte ho.

    Example

    class User(db.Model):
        id = db.Column(db.Integer, primary_key=True)
        email = db.Column(db.String(120), unique=True)
    
    User.query.get(5)  # SELECT ... WHERE id=5
  2. 2
    did u implement JWT tokens (if not then y and what u did)
    Times asked 2
    Official solution

    SimpleJWT teen tukde ki signed chitthi: header.payload.signature. Padhi ja sakti hai, badli nahi ja sakti.

    Encoded (Base64) + signed, encrypted nahi (JWE alag). Payload mein password mat daalo — koi jwt.io pe dekh lega.

    Login pe server secret se HMAC (HS256). Har API Authorization: Bearer <token>.
    Expiry exp. Change payload → signature fail → 401.

    Session MAD1 server yaad rakhta. JWT MAD2 client rakhta, server stateless-ish.

    Example

    eyJhbGciOiJIUzI1NiJ9.{"sub":1,"role":"admin"}.signature
    # Authorization: Bearer <token>

    Project example: POST /login → token LS. fetch interceptor header. @jwt_required APIs.

    Viva tipAlgo HS256. Secret env var. jwt.io pe payload dikhao, secret public site pe mat paste.

  3. 3
    and smth else idr
    Times asked 2
    Official solution

    SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.

Advice: show ur demo properly i was lucky as he was in a hurry as he had another viva so he left me within 15-20 mins and also so luckily no code making and code changes . but i had rescheduled from thur 530 pm to fri 630 pm. be confident and be honest as much as possible especially in the more important stuff u shd others viva for same proctor its best coz he was in hurry for me so was just wanting me to finish fast so he just said to everything i said
  1. 1
    - Celery task modification
    Times asked 2
    Official solution

    SimpleCelery = background naukri. HTTP request ko 10 second email bhejne ke liye mat rokna.

    Distributed task queue: aap function ko abhi nahi, worker process mein later/retry/schedule pe chalaate ho.

    MAD2 typical jobs: daily reminder mail, monthly HTML report, user-triggered CSV export.

    Web request 200ms hona chahiye. 10,000 emails request thread mein = timeout. Worker alag CPU pe kaam kare.

    Redis broker chahiye. Beat alag process schedule ke liye.

    Example

    @celery.task
    def daily_reminder():
        for u in User.query.filter_by(active=True):
            send_mail(u.email, 'Book something today!')

    Project example: User Export click → 202 Accepted. Worker CSV + email. Daily 6pm Beat reminder.

    Viva tipWorker + Redis bina Beat ke user-triggered chalega. Scheduled jobs ke liye Beat bhi chahiye.

  2. 2
    - Cache and its implementation
    Times asked 2
    Official solution

    SimpleCache = pehli baar hisaab karke copy rakh lo, doosri baar copy dikha do.

    Baar-baar same expensive kaam (DB query, counting bookings) mat karo. Result Redis jaise store mein timeout ke saath rakh do.

    Cache hit: key mil gayi, DB skip. Cache miss: DB se lao, SET karo, return karo.

    Tradeoff: speed vs stale data. Admin naya venue add kare aur cache 50s ka ho to user purani list dekh sakta hai — isliye write pe invalidation zaroori hai.

    Browser cache, Flask-Caching, Redis alag layers hain. MAD2 examiner Redis + @cache.cached code dekhta hai.

    Example

    @cache.cached(timeout=50, query_string=True)
    @app.route('/api/shows')
    def shows():
        return jsonify([s.serialize() for s in Show.query.all()])

    Project example: Admin dashboard counts / venues list cache. Create/update/delete ke baad cache.delete('venues').

    Viva tipprint('DB queried') function ke andar laga ke miss/hit demo karo — hit pe print nahi chalega.

  3. 3
    - Whether I used AI for the frontend
    Times asked 2
    Official solution

    SimpleMAD1 frontend usually Jinja templates + HTML/CSS/Bootstrap (+ thoda JS). MAD2 pe Vue ho to clearly bolo.

Advice: Guy was chill; please present your app in a good way; That should be sufficient.
  1. 1
    << Level2 Viva
    Times asked 2
    Official solution

    SimpleLevel = viva difficulty band. Level 1 usually demo + basics; higher pe live coding + deeper theory.

    Viva tipJo level assign hai uske hisaab se demo + theory ready rakho.

  2. 2
    - Demo of the application
    Times asked 1
    Official solution

    SimpleDemo script pehle se practice: 5–7 min, Admin + User roles, saare mandatory features.

    Suggested flow1) Register/login user
    2) Admin login — CRUD
    3) Approval/blacklist
    4) Booking/apply + edge case
    5) Search
    6) Logout

    Viva tipBolte-bolte dikhao. Code tab kholna jab poochhein.

  3. 3
    - Vuex (I had used pinia for state management)
    Times asked 2
    Official solution

    SimplePinia naya store: mutations nahi, seedha state. Vue 3 recommended.

    defineStore. Vuex vs Pinia: naya project Pinia. Purana Vuex valid.

    Component = reusable UI block (Navbar, Card). Props parent→child data, emit child→parent event. Slots parent HTML inner content.

    computed cache + reactive derive (filtered list). watch side-effect (query change pe API). methods events. ref() primitive, reactive() object. Vuex/Pinia global store; localStorage persist, store nahi.

    SFC: template + script + style ek .vue file. Parent-child exam favourite: list parent, row child :item + @delete.

    Project example: stores/user.js. Agar Vuex hai to Pinia ka naam mat lo unless used.

  4. 4
    then some other theory question
    Times asked 2
    Official solution

    SimpleTheory = concepts: ORM, MVC, auth vs authz, Jinja inheritance, sessions. 1-line def + project example.

  5. 5
    -- Code Changes
    Times asked 2
    Official solution

    Yeh MAD-1 viva question tumhare project ke context se linked hai. Short answer is structure se do:

    Pehle 1 line definition/purpose, phir tumhare project ka example, phir chhota code/flow.

    Typical Flask flowBrowser request → @app.route controller → SQLAlchemy model/DB → Jinja template response.

    Auth: session['user_id'] + role check. CRUD: add/commit, query.all, field update, delete.
    Live change maange to: related model → route → template, phir browser refresh karke dikhao.

    Example (generic create):
    obj = Model(name=request.form.get('name'))

    db.session.add(obj); db.session.commit()
    return redirect(url_for('list_view'))
  6. 6
    - Make the parking lot name case sensitive so it given an error (Like python treats uppercase and lowercase different like IITM and iitm is different but the name is same, so I implemented that.)
    Times asked 2
    Official solution

    SimpleProject overview: problem → roles → main entities → key flows (register, book, admin approve).

    Viva tip1 minute elevator pitch ready rakho, phir demo.

Advice: Chill proctor, theory should be good, go through your code thoroughly.
  1. 1
    Asked me work on both admin and user side
    Times asked 2
    Official solution

    SimpleDemo script pehle se practice: 5–7 min, Admin + User roles, saare mandatory features.

    Suggested flow1) Register/login user
    2) Admin login — CRUD
    3) Approval/blacklist
    4) Booking/apply + edge case
    5) Search
    6) Logout

    Viva tipBolte-bolte dikhao. Code tab kholna jab poochhein.

  2. 2
    Asked me to explain a route, how it is stored in db
    Times asked 2
    Official solution

    SimpleCode explain formula: input kya aaya → auth/validation → DB change → response/UI.

    Viva tipFunction signature + 3-4 important lines + edge case.

  3. 3
    what are all the ways to declare a variable in JS
    Times asked 2
    Official solution

    SimpleJS variables: var (function scope, old), let (block), const (block, reassign nahi).

    Example

    let count = 0;
    const API = '/api';
  4. 4
    He didn't ask me to code.
    Times asked 2
    Official solution

    SimpleLive Flask coding: chhota route likho, save, browser/curl se test. Syntax error terminal mein padho.

    Example

    @app.route('/ping')
    def ping():
        return jsonify(ok=True)
    
    @app.route('/even/<int:n>')
    def even(n):
        return 'even' if n % 2 == 0 else 'odd'
Advice: Chill proctor. you are safe
  1. 1
    Show demo
    Times asked 11
    Official solution

    SimpleDemo script pehle se practice: 5–7 min, Admin + User roles, saare mandatory features.

    Suggested flow1) Register/login user
    2) Admin login — CRUD
    3) Approval/blacklist
    4) Booking/apply + edge case
    5) Search
    6) Logout

    Viva tipBolte-bolte dikhao. Code tab kholna jab poochhein.

  2. 2
    How is cost being calculated?
    Times asked 2
    Official solution

    SimpleCode explain formula: input kya aaya → auth/validation → DB change → response/UI.

    Viva tipFunction signature + 3-4 important lines + edge case.

  3. 3
    How did you do charts?
    Times asked 2
    Official solution

    SimpleCode explain formula: input kya aaya → auth/validation → DB change → response/UI.

    Viva tipFunction signature + 3-4 important lines + edge case.

  4. 4
    Where are tokens stored?
    Times asked 3
    Official solution

    SimpleLS / SS / memory / httpOnly cookie. Har request Authorization header.

    Logout clear. XSS LS risk. Memory refresh lose.

    Authentication poochta hai "tu kaun hai?", Authorization poochta hai "tujhe yeh kaam karne ki permission hai?"

    Authentication: login. Username + password hash check. Success pe JWT/session. Galat credentials = 401.
    Authorization: uske baad role. Admin hi venue/lot delete kare, student nahi = 403 (logged in ho, allowed nahi).

    MAD2: POST /api/login = authentication. @jwt_required identity. @roles_required('admin') ya Vue v-if="isAdmin" = authorization. Frontend hide sirf UX — asli deny backend pe.

    Validation alag: form sahi bhara (email format, age 18+). Woh identity prove nahi karta. Password store hash (Werkzeug), JWT payload padha ja sakta hai isliye secret mat daalo.

    Example

    localStorage.setItem('token', data.token)
    localStorage.removeItem('token')

    Project example: login.vue setItem. interceptor getItem. logout removeItem.

    Viva tipSession Storage tab band pe saaf. Cookies expiry + httpOnly. Vuex memory refresh pe gayab — persist alag.

  5. 5
    Open a notepad and create a login routing function from scratch
    Times asked 2
    Official solution

    SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.

Advice: Just read your code thoroughly, go through questions in this sheet, and practice practice practice the frequently asked tasks in viva.
  1. 1
    - Proctor asked me to code a celery task (of addition of 2 numbers) connected to a backend api route & then create a .vue component with a button which executes the task
    Times asked 2
    Official solution

    SimpleCelery = background naukri. HTTP request ko 10 second email bhejne ke liye mat rokna.

    Distributed task queue: aap function ko abhi nahi, worker process mein later/retry/schedule pe chalaate ho.

    MAD2 typical jobs: daily reminder mail, monthly HTML report, user-triggered CSV export.

    Web request 200ms hona chahiye. 10,000 emails request thread mein = timeout. Worker alag CPU pe kaam kare.

    Redis broker chahiye. Beat alag process schedule ke liye.

    Example

    @celery.task
    def daily_reminder():
        for u in User.query.filter_by(active=True):
            send_mail(u.email, 'Book something today!')

    Project example: User Export click → 202 Accepted. Worker CSV + email. Daily 6pm Beat reminder.

    Viva tipWorker + Redis bina Beat ke user-triggered chalega. Scheduled jobs ke liye Beat bhi chahiye.

  2. 2
    - what is typescript coercion ?
    Times asked 2
    Official solution

    SimpleType coercion = auto type convert (JS '5'+1 → '51'). Strict === prefer karo. TypeScript types coercion kam karta hai.

  3. 3
    - difference between v-if & v-show
    Times asked 1
    Official solution

    Simplev-if ghar se nikaal deta hai (DOM se). v-show sirf light band karta hai (display:none).

    v-if false → element exist hi nahi — costly create/destroy, lekin secret HTML DOM mein nahi.
    v-show → hamesha DOM, CSS hide, toggle tez.

    Rare / permission UI: v-if (admin panel). Dropdown bar-bar: v-show.

    : shorthand v-bind ka, v-if ka nahi.

    Example

    <div v-if="isAdmin">Admin panel</div>
    <div v-show="open">Dropdown</div>

    Project example: Admin links v-if="role==='admin'". FAQ accordion v-show="open".

    Viva tipSecurity ke liye sirf v-if kaafi nahi — API 403 bhi chahiye.

  4. 4
    - : is a shortform for which vue property?
    Times asked 2
    Official solution

    SimpleORM = Object Relational Mapping. Tables → Python classes. Raw SQL kam likhte ho.

    Example

    class User(db.Model):
        id = db.Column(db.Integer, primary_key=True)
        email = db.Column(db.String(120), unique=True)
    
    User.query.get(5)  # SELECT ... WHERE id=5
  5. 5
    - what are slots ?
    Times asked 1
    Official solution

    SimpleSlots = dabbe ke andar parent apna HTML daal de. Props data, slots markup.

    Default slot, named slots. App.vue router-view layout jaisa outlet.

    Agar nahi use kiya: 'layout router-view se kiya' valid.

    Component = reusable UI block (Navbar, Card). Props parent→child data, emit child→parent event. Slots parent HTML inner content.

    computed cache + reactive derive (filtered list). watch side-effect (query change pe API). methods events. ref() primitive, reactive() object. Vuex/Pinia global store; localStorage persist, store nahi.

    SFC: template + script + style ek .vue file. Parent-child exam favourite: list parent, row child :item + @delete.

    Example

    <div class="card"><slot>Default</slot></div>
    <Card><p>Custom body</p></Card>

    Project example: Card.vue <slot>Default</slot>. Parent custom body.

  6. 6
    - what are the navigational guards w.r.t vue router?
    Times asked 1
    Official solution

    SimpleVue = UI ka smart assistant. Data badlo, screen khud update. MAD1 Jinja har click pe naya HTML.

    Progressive frontend framework. Components, reactivity, directives.

    MAD2 SPA: ek index.html, Vue Router pages, Flask sirf JSON.

    Fayde: easy, SFC, docs. Vs React: templates HTML-like, course sikhata hai. Vs plain JS: baar-baar DOM mat chhedo.

    Example

    <!-- HelloWorld.vue -->
    <template>
      <h1>{{ msg }}</h1>
    </template>
    <script>
    export default { data() { return { msg: 'Hello' } } }
    </script>

    Project example: Navbar.vue + views (Login, Dashboard). data() / setup() reactive. fetch APIs.

    Viva tipFayde: easy, SFC, reactivity. Vs React: chhota learning curve. Vs plain JS: UI state auto-update.

  7. 7
    - what are the function of call(), apply(), bind() properties of vue JS ?
    Times asked 2
    Official solution

    SimpleVue = UI ka smart assistant. Data badlo, screen khud update. MAD1 Jinja har click pe naya HTML.

    Progressive frontend framework. Components, reactivity, directives.

    MAD2 SPA: ek index.html, Vue Router pages, Flask sirf JSON.

    Fayde: easy, SFC, docs. Vs React: templates HTML-like, course sikhata hai. Vs plain JS: baar-baar DOM mat chhedo.

    Example

    <!-- HelloWorld.vue -->
    <template>
      <h1>{{ msg }}</h1>
    </template>
    <script>
    export default { data() { return { msg: 'Hello' } } }
    </script>

    Project example: Navbar.vue + views (Login, Dashboard). data() / setup() reactive. fetch APIs.

    Viva tipFayde: easy, SFC, reactivity. Vs React: chhota learning curve. Vs plain JS: UI state auto-update.

  8. 8
    - how does a grandparent pass on data to grandchild in case of a nested route in vue router & how does a grandchild transfer data to grandparent ?
    Times asked 2
    Official solution

    SimpleBaat: props se neeche, emit se upar. Door ke rishte: store ya provide/inject.

    Grandparent→grandchild props drilling ugly. Vuex/Pinia ya provide('user').

    Did you use? List+card files naam lo.

    Pehle 1-line definition, phir related MAD2 layer (Vue SFC / Flask route / models.py / tasks.py / Redis).

    4-line formula: input kahan se aaya, auth/validation kaunsa, DB ya cache ya Celery, kya return.

    Related mix mat karo — cache ≠ Celery, authentication ≠ authorization, v-if ≠ v-show, Beat ≠ Worker. Follow-up ke liye ek difference ready rakho.

    Example

    provide('user', user)
    const user = inject('user')

    Project example: Dashboard v-for BookingCard. Card emit 'cancel'.

    Viva tip3+ level props drilling se better store. Navbar user info store se lo.

  9. 9
    - what is the difference between @cache.cached & @cache.memoize ?
    Times asked 1
    Official solution

    Simplecached poori view ko yaad rakhta hai, memoize function ke arguments ke hisaab se.

    @cache.cached URL / key_prefix (optional query_string) se key banata hai — list endpoints ke liye.
    @cache.memoize arguments se key banata hai — get_user(5) aur get_user(9) alag cache.

    Prefix clash se galat data mil sakta hai. Dono ka timeout same idea hai. Invalidation: delete_memoized(fn, args) vs cache.delete(prefix).

    Example

    @cache.cached(timeout=30, key_prefix='home')
    def home(): ...
    
    @cache.memoize(30)
    def get_user(user_id): ...  # alag key per user_id

    Project example: Venues list = cached. User-wise report function = memoize(user_id).

    Viva tipList endpoint: cached. Function with arguments: memoize. Prefix alag rakho warna clash.

  10. 10
    - Redis is a message broker between which 2 entities ?
    Times asked 1
    Official solution

    SimpleRedis. Alternative RabbitMQ. Course Redis because cache bhi.

    Between Flask client and Celery worker.

    Celery Python ka distributed task queue — HTTP request ko 10s email/CSV ke liye mat rokna.

    Flow: Flask .delay() → Redis broker → Worker execute. Beat alag process hai (clock): crontab padhke due time pe queue mein daalta hai. Beat khud mail nahi bhejta; Worker haath hai.

    MAD2 typical: daily reminder (Beat), monthly report (Beat), user Export CSV (button, Beat nahi). JS async/await browser event loop hai, Celery server-side process — mix mat karo.

    Demo: tin terminals — redis-server, celery worker, celery beat — plus Flask. MailHog :8025 inbox. Result backend se task SUCCESS poll optional.

    Project example: broker_url redis://localhost:6379/0

Advice: Please be calm & dont panic, practise all the coding questions form the spreadsheet particular to this proctor & you are good to go.
  1. 1
    show model.py
    Times asked 2
    Official solution

    Simplemodels.py = har table ki class: columns, PK/FK, relationships. Yeh Model layer hai.

    Suggested flow1) Classes list karo
    2) Har table ka kaam 1 line
    3) Relationships (1-M / M-M)
    4) Constraints (unique, nullable)

    Example

    class Lot(db.Model):
        id = db.Column(db.Integer, primary_key=True)
        name = db.Column(db.String(80), nullable=False)
        spots = db.relationship('Spot', backref='lot', lazy=True)
  2. 2
    what is lazy( wrt models )
    Times asked 2
    Official solution

    Simplemodels.py = har table ki class: columns, PK/FK, relationships. Yeh Model layer hai.

    Suggested flow1) Classes list karo
    2) Har table ka kaam 1 line
    3) Relationships (1-M / M-M)
    4) Constraints (unique, nullable)

    Example

    class Lot(db.Model):
        id = db.Column(db.Integer, primary_key=True)
        name = db.Column(db.String(80), nullable=False)
        spots = db.relationship('Spot', backref='lot', lazy=True)
  3. 3
    write code to implement v-if, v-else
    Times asked 2
    Official solution

    Simplev-if ghar se nikaal deta hai (DOM se). v-show sirf light band karta hai (display:none).

    v-if false → element exist hi nahi — costly create/destroy, lekin secret HTML DOM mein nahi.
    v-show → hamesha DOM, CSS hide, toggle tez.

    Rare / permission UI: v-if (admin panel). Dropdown bar-bar: v-show.

    : shorthand v-bind ka, v-if ka nahi.

    Example

    <div v-if="isAdmin">Admin panel</div>
    <div v-show="open">Dropdown</div>

    Project example: Admin links v-if="role==='admin'". FAQ accordion v-show="open".

    Viva tipSecurity ke liye sirf v-if kaafi nahi — API 403 bhi chahiye.

  4. 4
    how auth_token was created
    Times asked 2
    Official solution

    SimpleCode explain formula: input kya aaya → auth/validation → DB change → response/UI.

    Viva tipFunction signature + 3-4 important lines + edge case.

  1. 1
    Don't remember excatly- mostly one frontend , backend , routes by just seeing db , add frontend code.
    Times asked 2
    Official solution

    SimpleMAD1 frontend usually Jinja templates + HTML/CSS/Bootstrap (+ thoda JS). MAD2 pe Vue ho to clearly bolo.

Advice: He is unpredictable , can ask anything, be thorough with your code . Just make sure you know what you are doing and he does give 2nd chance , if you ask ( basically burry you) , be prepare to write code on notebook
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