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Lazy IITians

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Question sets

  1. 1
    Index.html se open kyu kr rha h change the port aur phir open kro
    Times asked 2
    Official solution

    SimpleLive UI change: relevant CSS/HTML template kholo — color, margin, flex, bootstrap class. Save + hard refresh.

    Example

    /* button red */
    .btn-primary { background: red; }
    
    /* center navbar item */
    .navbar { justify-content: center; }

    Viva tipDevTools se pehle try, phir file mein permanent change.

  2. 2
    Console khol ke koi error aa rha usko thiq kro
    Times asked 2
    Official solution

    SimpleDebug: terminal traceback padho, print/logging, Flask debug, browser Network/Console, reproduce minimum steps.

  3. 3
    Token based authentication vs session based authentication with code example
    Times asked 1
    Official solution

    SimpleMAD1 mein usually session-based auth: login pe session['user_id'], har request pe verify.

    Example

    session['user_id'] = user.id
    uid = session.get('user_id')
    user = User.query.get(uid)

    Viva tipSECRET_KEY set karo warna session insecure. logout pe session.clear().

  4. 4
    Cdn why not cli
    Times asked 2
    Official solution

    SimpleCDN = Vue script tag se, jaise pen drive. CLI/Vite = poori factory (SFC, npm, bundle).

    CDN: no build, chhote apps, exam PC pe Node nahi to bhi chal. Weak: no .vue compile, 3rd-party cache, scale/team.

    CLI/Vite: Single File Components, env, code-split, production dist/. Scalable.

    Examiner 'which + why' — jo use kiya wahi justify, doosra naam rato mat.

    Example

    <!-- CDN -->
    <script src="https://unpkg.com/vue@3/dist/vue.global.js"></script>
    
    # Vite
    npm run dev
    npm run build

    Project example: CDN: index.html unpkg vue. CLI: package.json, npm run serve / vite.

    Viva tipCDN scalable large teams ke liye weak (no SFC compile, caching 3rd party). Examiner 'which + why' poochta hai — jo use kiya wahi justify karo.

  5. 5
    Create a new model.py
    Times asked 1
    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)
  6. 6
    Admin dashboard ka side bar recreate kro
    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.

  7. 7
    Route banao nye to fetch an api call
    Times asked 2
    Official solution

    SimplePehle 1-line definition, phir apne MAD1 project mein file dikhao, phir chhota example.

    Suggested flow1) Concept kya hai?
    2) Mere code mein kahan?
    3) Example / demo
    4) Edge case

    Example

    # related file: models.py / routes / template
    # formula: request → check/auth → DB → render/redirect

    Viva tipExact line yaad nahi to honestly related part dikhao. Bluff mat karo.

  8. 8
    Ek aur route to delete
    Times asked 2
    Official solution

    SimplePehle 1-line definition, phir apne MAD1 project mein file dikhao, phir chhota example.

    Suggested flow1) Concept kya hai?
    2) Mere code mein kahan?
    3) Example / demo
    4) Edge case

    Example

    # related file: models.py / routes / template
    # formula: request → check/auth → DB → render/redirect

    Viva tipExact line yaad nahi to honestly related part dikhao. Bluff mat karo.

  9. 9
    Sql query to fetch users who have registered
    Times asked 2
    Official solution

    SimplePehle 1-line definition, phir apne MAD1 project mein file dikhao, phir chhota example.

    Suggested flow1) Concept kya hai?
    2) Mere code mein kahan?
    3) Example / demo
    4) Edge case

    Example

    # related file: models.py / routes / template
    # formula: request → check/auth → DB → render/redirect

    Viva tipExact line yaad nahi to honestly related part dikhao. Bluff mat karo.

  10. 10
    Css file explanation each line in deatil
    Times asked 2
    Official solution

    SimpleCSS look. Selectors element .class #id. Box model flex grid.

    Inline vs internal vs external. Specificity inline high.

    Look: Bootstrap utility classes (margin m-3, flex, grid) ya khud CSS. Responsive = media query / Bootstrap breakpoints se mobile.

    Vue scoped style leak nahi. :class binding. Examiner colour/button live change maange to DevTools nahi, source class dikhao.

    CSS ≠ Bootstrap. Bootstrap CSS+JS framework. Inline style last resort.

    Example

    .btn { background: green; }
    .mt-2 { margin-top: .5rem; }  /* bootstrap */
    .my-3 { margin-top+bottom }

    Project example: style section SFC scoped + bootstrap.

    Viva tipResponsive: Bootstrap grid / media queries. Bina CSS possible nahi really — browser default ugly. Flexbox 1D, Grid 2D.

  11. 11
    Demo
    Times asked 9
    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.

Advice: Bch ke rhna
  1. 1
    - Collaborator
    Times asked 2
    Official solution

    SimpleGitHub repo open karo: commits, collaborators, README. Examiner check karta hai tumne khud kaam kiya.

    Example

    Settings → Collaborators
    Commits: regular messages, last-day dump nahi.

    Viva tipPrivate repo access pehle de do. Main branch submitted ZIP se match honi chahiye.

  2. 2
    - Start with demo
    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.

  3. 3
    - Asked about some code from project
    Times asked 2
    Official solution

    SimpleCode dikhao to pehle related file: models → route → template. Flow explain karte hue lines padho.

  4. 4
    - 1 way 2 way binding
    Times asked 2
    Official solution

    SimpleUngli rakhe to 4-line formula — panic ki jagah structure.

    1) File ka role: model / Flask route / Vue SFC / celery task / config
    2) Input kahan: JSON, params, token, props, $route
    3) Kya kaam: query, cache, validation, .delay()
    4) Output: jsonify, this.items, email, redirect

    Unknown keyword: import, decorator, if, commit — har ka reason. Bluff mat.

    Suggested flow1) Kaunsi layer?
    2) Input?
    3) DB/cache/task?
    4) Response/UI?

    Project example: Booking POST: jwt, seats check, commit, 201, Vue list push.

    Viva tipUnknown keyword: import, decorator, if, commit — har ka reason. Panic mat.

  5. 5
    - some vue basic questions
    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.

  6. 6
    Coding part
    Times asked 2
    Official solution

    SimpleLive coding: notepad/editor mein chhota Flask route / Jinja loop / model field. Calm raho, run karke dikhao.

  7. 7
    - basic vue component implementing a button when clicked prints "HI"
    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
    - basic api which takes date of birth as input and gives age as output
    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: - Very patient and kind proctor. Dont worry, he gives time for everything, just be calm. - He is chill. - Just know your code and make sure everything works fine. - he will give a nice feedback at the end of viva and explain what all went wrong etc.
  1. 1
    Show me collaborator 1.What is lifecycle hooks
    Times asked 2
    Official solution

    SimpleGitHub repo open karo: commits, collaborators, README. Examiner check karta hai tumne khud kaam kiya.

    Example

    Settings → Collaborators
    Commits: regular messages, last-day dump nahi.

    Viva tipPrivate repo access pehle de do. Main branch submitted ZIP se match honi chahiye.

  2. 2
    Did you used token based or session based. 3.Where is token stored 4.What is celery and how it works
    Times asked 2
    Official solution

    SimpleMAD1 mein usually session-based auth: login pe session['user_id'], har request pe verify.

    Example

    session['user_id'] = user.id
    uid = session.get('user_id')
    user = User.query.get(uid)

    Viva tipSECRET_KEY set karo warna session insecure. logout pe session.clear().

  3. 3
    Show me your model.py and tell me what is lazy loading
    Times asked 2
    Official solution

    Simplelazy loading: related objects kab load hon. lazy=True default (access pe query). joined/eager pehle se join.

  4. 4
    Write a vue component for a button. When click it say hi.
    Times asked 2
    Official solution

    SimpleComponent + route ya template v-if/v-for/fetch. :key dena.

    Clock interval + clear. Add numbers v-model.number. New page routes.js.

    Examiner 2 cheezein: simple desi line + tumhare project ki exact file.

    Pehle ID, GitHub, portal ZIP. Phir run: Redis + Flask + worker + beat + Vue. Feature demo: login, RBAC, cache hit/miss, Celery mail, search.

    Line pe ungli: input kahan, kaunsa check, query/cache/task, JSON/UI. Copilot band. Jo nahi kiya honestly bolo + kaise add karte.

    Example

    <input v-model.number="a"><input v-model.number="b">
    <p>{{ a + b }}</p>

    Project example: views/Foo.vue + path. mounted fetch if API.

  5. 5
    Write a vue router for the dob. That take dob as a input and print the date of birth.
    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'
  6. 6
    And then demonstration of the project with all core functionalities
    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.

Advice: Keep practicing this sheet .
  1. 1
    - make a hello world flask route
    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'
  2. 2
    - what is celery and redis? how do they work together
    Times asked 2
    Official solution

    SimpleRedis box hai, Celery us box se kaam uthane wala worker hai — same cheez nahi.

    Redis: store (cache keys) + queue (broker lists).
    Celery: Python library jo tasks define karti hai, .delay() se queue mein daalti hai, worker execute karta hai.

    Dono localhost pe ho sakte hain. Alag Redis DB index use karo. Redis band = cache miss + Celery stuck.

    Example

    Celery: broker_url='redis://localhost:6379/0'
    Cache:  CACHE_REDIS_URL='redis://localhost:6379/1'

    Project example: export_csv.delay(user_id) Flask se. Worker Redis se task uthata hai, CSV+email. Cache alag keys venues.

    Viva tipAgar possible ho to cache db=1, broker db=0 — keys mix nahi hoti.

  3. 3
    - change a random background colour
    Times asked 2
    Official solution

    SimpleLive UI change: relevant CSS/HTML template kholo — color, margin, flex, bootstrap class. Save + hard refresh.

    Example

    /* button red */
    .btn-primary { background: red; }
    
    /* center navbar item */
    .navbar { justify-content: center; }

    Viva tipDevTools se pehle try, phir file mein permanent change.

  4. 4
    - where is vue being used?
    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.

  5. 5
    - cache and where are the cached files located.
    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.

  1. 1
    Download and run
    Times asked 1
    Official solution

    SimpleExaminer submitted ZIP chahta hai, local extra changes nahi.

    Portal se ZIP download → extract → venv → pip install -r requirements.txt → flask run / python app.py.
    Checksum maange to hash match karke dikhao. Camera/OPPE setup unke instructions.
    Linux/Mac: paths, gunicorn; Windows paths alag ho to relative paths use karo.
    Do browsers: admin + user parallel demo impressive lagta hai.

  2. 2
    Cdn vs cli
    Times asked 3
    Official solution

    SimpleCDN = Vue script tag se, jaise pen drive. CLI/Vite = poori factory (SFC, npm, bundle).

    CDN: no build, chhote apps, exam PC pe Node nahi to bhi chal. Weak: no .vue compile, 3rd-party cache, scale/team.

    CLI/Vite: Single File Components, env, code-split, production dist/. Scalable.

    Examiner 'which + why' — jo use kiya wahi justify, doosra naam rato mat.

    Example

    <!-- CDN -->
    <script src="https://unpkg.com/vue@3/dist/vue.global.js"></script>
    
    # Vite
    npm run dev
    npm run build

    Project example: CDN: index.html unpkg vue. CLI: package.json, npm run serve / vite.

    Viva tipCDN scalable large teams ke liye weak (no SFC compile, caching 3rd party). Examiner 'which + why' poochta hai — jo use kiya wahi justify karo.

  3. 3
    Jwt
    Times asked 1
    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.

  4. 4
    Phir kuch error aa rha tha usme kha error dhund ke correct kro maiine kiya
    Times asked 2
    Official solution

    SimplePehle 1-line definition, phir apne MAD1 project mein file dikhao, phir chhota example.

    Suggested flow1) Concept kya hai?
    2) Mere code mein kahan?
    3) Example / demo
    4) Edge case

    Example

    # related file: models.py / routes / template
    # formula: request → check/auth → DB → render/redirect

    Viva tipExact line yaad nahi to honestly related part dikhao. Bluff mat karo.

  5. 5
    Fir caching aur kha implement kiya
    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.

  6. 6
    Phir model.py ki random line ko explain kro
    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)
  7. 7
    Lazy loading
    Times asked 2
    Official solution

    Simplelazy loading: related objects kab load hon. lazy=True default (access pe query). joined/eager pehle se join.

  8. 8
    Single page app
    Times asked 2
    Official solution

    SimpleMAD1 typical: Browser → Flask routes → validate/auth → SQLAlchemy → SQLite → Jinja response.

    Suggested flowRequest → Route → Auth check → DB → render_template / redirect

  9. 9
    Phir last me 5 min hai edge cases dhundo aur correct kro
    Times asked 2
    Official solution

    SimpleEdge cases: duplicate booking, full capacity, wrong role URL, empty search, invalid id.

    Example

    if Spot.query.get_or_404(spot_id).status != 'available':
        flash('Already taken')
        return redirect(...)
  10. 10
    Phir sidebar ka color change then last me khta
    Times asked 2
    Official solution

    SimpleLive UI change: relevant CSS/HTML template kholo — color, margin, flex, bootstrap class. Save + hard refresh.

    Example

    /* button red */
    .btn-primary { background: red; }
    
    /* center navbar item */
    .navbar { justify-content: center; }

    Viva tipDevTools se pehle try, phir file mein permanent change.

  11. 11
    Feedback bola toh khta u have explained enough good
    Times asked 2
    Official solution

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

Advice: Shi bnda h
See reviews 103 MAD1 Level 1
  1. 1
    Difference between authorization and authentication
    Times asked 2
    Official solution

    SimpleAuthentication: tu kaun hai? (login). Authorization: tujhe permission hai? (role check).

    Example

    # auth
    if check_password_hash(user.password, pwd):
        session['user_id'] = user.id
    
    # authz
    if user.role != 'admin':
        abort(403)
  2. 2
    Async/await
    Times asked 2
    Official solution

    Examiner code pe ungli rakh ke poochta hai — panic mat karo, 4-line formula bolo.

    1) Yeh file/line kya role hai (model / route / template / config)?
    2) Input kahan se aata hai (form, URL <id>, session, JSON)?
    3) DB pe kya query/write?
    4) Output kya (render_template / redirect / jsonify)?

    Example

    @app.route('/book/<int:id>', methods=['POST']) — logged-in user session se, trek id URL se, Booking add, slots--, redirect history.

    Unknown line: imports (request, url_for, flash), decorators, if checks, commit — har keyword ka reason ready rakho.

  3. 3
    Login function
    Times asked 2
    Official solution

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

Advice: For viva 1, just go through your project thoroughly
  1. 1
    LEVEL 1
    Times asked 6
    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
    - show id card
    Times asked 2
    Official solution

    SimpleCamera pe clearly college/IITM ID dikhao — naam aur photo match hone chahiye.

    Viva tipPehle se ID haath mein rakho, glare mat aane do. Iske baad GitHub + project run.

  3. 3
    - show collaborators
    Times asked 2
    Official solution

    SimpleGitHub repo open karo: commits, collaborators, README. Examiner check karta hai tumne khud kaam kiya.

    Example

    Settings → Collaborators
    Commits: regular messages, last-day dump nahi.

    Viva tipPrivate repo access pehle de do. Main branch submitted ZIP se match honi chahiye.

  4. 4
    - token or session management
    Times asked 2
    Official solution

    SimpleMAD1 mein usually session-based auth: login pe session['user_id'], har request pe verify.

    Example

    session['user_id'] = user.id
    uid = session.get('user_id')
    user = User.query.get(uid)

    Viva tipSECRET_KEY set karo warna session insecure. logout pe session.clear().

  5. 5
    - show where tokens are being generated in backend
    Times asked 1
    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.

  6. 6
    - lifecycle hooks in Vue with examples
    Times asked 1
    Official solution

    SimpleLifecycle = component ki zindagi ke stages. API call tab jab DOM ready ho — mounted.

    created: instance bani, this data, DOM nahi. mounted/onMounted: page pe aa gaya — fetch, Chart.js, setInterval.
    updated: data change ke baad. unmounted: cleanup (clearInterval) warna memory leak.

    Dashboards onMounted isliye: canvas/API tab valid. created mein $el nahi.

    Composition: onMounted(() => {}) setup ke andar.

    Example

    export default {
      async mounted() {
        const r = await fetch('/api/venues')
        this.venues = await r.json()
      }
    }

    Project example: Venues.vue mounted fetch list. Clock component unmounted pe interval clear.

    Viva tipcreated: data setup, DOM nahi. mounted/onMounted: $el mil gaya — fetch yahi. Dashboards isliye onMounted use karti hain.

  7. 7
    - what is caching
    Times asked 1
    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.

  8. 8
    - when cache is hit, will the code run and hit the database? how does it work
    Times asked 1
    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.

  9. 9
    - asked to print("cached") and show it in the terminal and where it is being updated
    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.

Advice: be thorough with the basic functionality implementation and do not let him smell fear
  1. 1
    L2_Viva 1.Explain the file structure like location of celery job, scripts, routes etc
    Times asked 2
    Official solution

    Simplebackend create_app models api jobs. frontend src router. config env. README.

    Don't read every file. 6 roles.

    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.

    Project example: tree command or VSCode explorer.

  2. 2
    Explain what is broker and purpose of broker_url
    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
    Difference between Sql database and redis database? What type is redis database?-key-valuepair 4.Asked to show model.py file and asked to explain backref and secondary use.
    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)
  4. 4
    Token based authentication implementation and how hashing is done. Expected to explain the config setup for password hashing. 6.Where the token is getting saved ie server side or client side?
    Times asked 2
    Official solution

    SimplePassword plain text mat store. werkzeug generate_password_hash / check_password_hash.

    Example

    from werkzeug.security import generate_password_hash, check_password_hash
    user.password = generate_password_hash(raw)
    check_password_hash(user.password, raw)
  5. 5
    What is purpose of jsonify? 8.In JavaScript, what are different ways to initiate/create/define variables? -let,const,var
    Times asked 2
    Official solution

    Simplejsonify Python dict/list ko JSON response + proper Content-Type deta hai.

    Example

    return jsonify(message='ok', count=3), 200
  6. 6
    Show any Vue component and explain how it is mapped to url and quick walkthru of its structure?
    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.

  7. 7
    Asked If i am aware of parent and child component . If yes explain it and show where it is used?
    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.

  8. 8
    Show all the celery jobs that are implemented
    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.

  9. 9
    What are props in Vue
    Times asked 2
    Official solution

    SimpleVue.js frontend framework — reactive UI components. MAD2 mein common, MAD1 optional.

    Component: reusable UI (Navbar.vue) + data + template.
    Props: parent → child data. Child → parent: $emit('update', val).
    Slots: parent child ke andar extra HTML daal sakta hai.
    Lifecycle: created (data setup), mounted (DOM ready — API call), updated, unmounted.
    v-model two-way bind. Vue Router SPA routes (routes.js). Vuex/Pinia global state; mutations sync change, actions async.
    Standalone component: khud ke saath compile, parent register kam.

  10. 10
    What is watcher
    Times asked 1
    Official solution

    SimpleLifecycle hooks = component stages (created/mounted/updated/unmounted). Data fetch usually mounted/onMounted.

  11. 11
    What do you mean by Virtual DOM
    Times asked 2
    Official solution

    SimpleVirtual DOM memory tree. Diff, sirf farq real DOM pe. Fayda kam DOM ops. Nuksaan chhote page overhead.

    Vue/React. jQuery direct DOM. Lose reactivity Vue2 new property bina set.

    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.

    Project example: v-for list patch, poora innerHTML nahi.

Advice: Both L1 and L2 proctors were patient and were actively listening. Alteast be familiar with any two components implementation thoroughly. Second understand celery jobs and third models. I think this is bare minimum
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