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Lazy IITians

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Question sets

  1. 1
    firstly, he asked me to tell abt the project then give a demo while doing so he asked where is this function and all .
    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
    then he asked me to show my caching code, asked why it is used, what's vue.js why is that used, more ques on vue also gave suggestions.
    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
    basically was checking if I knew where the codes corresponding to the functions are.
    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.

  4. 4
    then gave a ques I the chat box -make a route to display all blacklisted users and then connect it to the frontend so all the blacklisted users are shown.
    Times asked 2
    Official solution

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

  5. 5
    ad then asked abt the difficulties faced, difference in experience from mad1 and mad2. that's about it.he is a really sweet guy will even saying good and in the gives his suggestion too.
    Times asked 2
    Official solution

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

Advice: be confident, he's very kind just chill.
  1. 1
    Backend-> celery 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
    Overall-> Authentication v/s Authorization, jwt pipeline theory(name only), show few features if exist
    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)
Advice: Just know your codebase
  1. 1
    Asked whether search bar is working or not
    Times asked 2
    Official solution

    SimpleSearch: form/query param → ilike filter → results template.

    Example

    q = request.args.get('q', '').strip()
    lots = Lot.query.filter(Lot.name.ilike(f'%{q}%')).all()
  2. 2
    Asked the functioning of create drive form in the company dashboard.
    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
  3. 3
    What are CRUD operations?
    Times asked 2
    Official solution

    SimpleCRUD = Create Read Update Delete. Admin pe ek resource ke 4 ops dikhao.

  4. 4
    Explain Vue lifecycle hooks.
    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.

  5. 5
    Explain Components of Vue.
    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
    LEVEL 2 VIVA
    Times asked 3
    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
    Introduce yourself, show your ID, and share your GitHub profile.
    Times asked 2
    Official solution

    Simple30 second: naam, degree, project kya hai, stack (Flask + Jinja + SQLAlchemy + SQLite).

    Example

    Main Priya, IITM BS. MAD1 mein parking/ticket app — Flask backend, Jinja templates, session login, SQLite.
  3. 3
    Download the app from the portal and start the setup. While doing the setup, she will ask questions like, "Why use a venv?" or "What is this and what is that?"
    Times asked 2
    Official solution

    SimpleExaminer portal wala submitted ZIP chahta hai. Local extra changes mat dikhana.

    Suggested flow1) Portal ZIP download
    2) Extract
    3) venv + pip install -r requirements.txt
    4) flask run / python app.py

  4. 4
    Give a demo of your app. (While you give the demo, she will also ask questions about what you are showing, such as frontend vs. backend validation. You can expect at least one question from every section you present.)
    Times asked 2
    Official solution

    SimpleValidation = input rules: required, email format, length, unique. Frontend UX, backend security — dono.

    Example

    if not email or '@' not in email:
        flash('Invalid email')
        return redirect(request.url)
    if User.query.filter_by(email=email).first():
        flash('Email taken')
  5. 5
    Explain the backend structure of your app. Inside this section, she will ask many questions (e.g., "What is Celery/Redis?", "What is a Beat vs. a Worker?", "Where are you configuring this or that?", "What authentication are you using?", "Where is it configured?", and "How does the data flow?" ).
    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)
Advice: You have to know your code thoroughly because she will ask questions from everywhere. If you know your code very well, her questions won't bother you. The question level is easy to moderate, though some are hard. She is an interactive, kind, and cool person. If you make a mistake, she will guide you too. All you have to do is be able to explain all of your code. Her main focus is to see your understanding and test it. All the best! 🤞
  1. 1
    Show id, GitHub collaborator, and commits
    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
    “tell me about caching”
    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
    Asked about CLI and CDN
    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.

  4. 4
    Open a notepad and write a route for login
    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'
  5. 5
    —in this he asked me what if the user gives empty values to email and password
    Times asked 2
    Official solution

    SimpleSMTP = Simple Mail Transfer Protocol — email bhejne ka standard. Flask-Mail / smtplib se reminders/reports.

    Example

    from flask_mail import Message
    msg = Message('Subject', recipients=[user.email])
    msg.body = 'Hello'
    mail.send(msg)

    Viva tipViva mein MailHog/inbox dikhao. Port 587 TLS common; local pe MailHog 1025.

  6. 6
    — fronted backend validation? Which can be easily bypassed?
    Times asked 2
    Official solution

    SimpleValidation = input rules: required, email format, length, unique. Frontend UX, backend security — dono.

    Example

    if not email or '@' not in email:
        flash('Invalid email')
        return redirect(request.url)
    if User.query.filter_by(email=email).first():
        flash('Email taken')
  7. 7
    — if front end validation was easily bypassed and empty values are given how will you handle?
    Times asked 2
    Official solution

    SimpleValidation = input rules: required, email format, length, unique. Frontend UX, backend security — dono.

    Example

    if not email or '@' not in email:
        flash('Invalid email')
        return redirect(request.url)
    if User.query.filter_by(email=email).first():
        flash('Email taken')
  8. 8
    Vue code to get info from user and call api for login
    Times asked 2
    Official solution

    SimpleLogin flow pehle poochta hai "tu kaun hai?", token milne ke baad har API pe wohi proof dikhate ho.

    Authentication step: Vue form email + password JSON POST karta hai. Flask user dhoondhta hai, check_password_hash se prove karta hai ki tum genuine ho. Galat 401. Sahi pe JWT + role milta hai — yeh session/token hai.

    Vue localStorage (ya cookie) mein token rakhta hai, dashboard pe router.push. Aage ki har fetch header: Authorization: Bearer <token>. @jwt_required identity check (authentication). @roles_required('admin') permission check (authorization) — logged in ho, lekin allowed nahi to 403.

    Validation alag cheez hai: empty email, password 8+ — form sahi bhara hai ya nahi. Woh identity prove nahi karta.

    Logout = client token delete + login page. Server blacklist optional. Password response JSON mein kabhi mat bhejo.

    Example

    # Authentication
    @app.route('/api/login', methods=['POST'])
    def login():
        u = User.query.filter_by(email=data['email']).first()
        if not u or not check_password_hash(u.password, data['password']):
            return jsonify(msg='bad'), 401
        return jsonify(token=create_access_token(u.id), role=u.role)
    
    # baad ki APIs
    # Authorization: Bearer <token>
    if current_user.role != 'admin':
        abort(403)

    Project example: Login.vue POST /api/login → token LS → interceptor. Student token se admin route = 403. Empty form = validation, galat password = 401.

    Viva tipNetwork tab mein password body dikhega localhost pe — prod HTTPS. Response mein hash/password echo mat karo.

Advice: He was not very responsive, he was too silent for so long. Maybe when he asks to write code, finish writing and Inform him you finished. Gives a little feedback at the end. However I messed up mine.
  1. 1
    Proctor: level2_141 (level 1)
    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
    Show GitHub and ID
    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.

  3. 3
    Download the code / do a checksum
    Times asked 2
    Official solution

    SimpleExaminer wohi ZIP chahta hai jo tumne submit kiya, local extra magic nahi.

    Portal download → extract → redis, venv, pip, npm, flask, worker, beat.

    Checksum maange to hash. Uncommitted files mat dikhana.

    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.

    Suggested flow1) ZIP
    2) Extract
    3) Redis + venv + pip
    4) npm/vite
    5) flask + celery worker + beat

    Project example: Submitted zip run. README commands copy.

    Viva tipChecksum maange to hash match karke dikhao. Extra uncommitted files mat dikhana.

  4. 4
    Show specific functions — create trek, register user, book a trek
    Times asked 2
    Official solution

    SimpleDemo 5–7 min ki kahani: saari roles, koi milestone skip nahi, bolte-bolte dikhao.

    Examiner list tick karta hai. Crash ho to panic nahi — terminal error padho.

    Code tab kholna jab poochhein. Extra uncommitted features mat dikhana agar portal ZIP mein nahi.

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

    Project example: Jo statement/parking/jobs/tickets hai uske user+admin journeys.

    Viva tipBol: 'Yahan overbooking rokta hoon'. Mandatory features pehle, polish baad.

  5. 5
    Show the monthly report and download the CSV
    Times asked 2
    Official solution

    SimpleLive jobs: Redis, worker, beat, crontab abhi, logs + email/CSV.

    Scheduled vs user-triggered dono dikhao. Missing feature honestly.

    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.

    Suggested flow1) redis
    2) worker
    3) beat
    4) crontab now
    5) logs + MailHog

    Example

    CELERY_BEAT_SCHEDULE = {
      'daily-reminder': {
        'task': 'jobs.daily_reminder',
        'schedule': crontab(hour=18, minute=0),
      },
    }

    Project example: Change schedule current time. MailHog. Export button 202.

  6. 6
    Show the APIs
    Times asked 2
    Official solution

    SimpleDemo 5–7 min ki kahani: saari roles, koi milestone skip nahi, bolte-bolte dikhao.

    Examiner list tick karta hai. Crash ho to panic nahi — terminal error padho.

    Code tab kholna jab poochhein. Extra uncommitted features mat dikhana agar portal ZIP mein nahi.

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

    Project example: Jo statement/parking/jobs/tickets hai uske user+admin journeys.

    Viva tipBol: 'Yahan overbooking rokta hoon'. Mandatory features pehle, polish baad.

  7. 7
    Show a Celery task executing (e.g. mail sending)
    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.

  8. 8
    What is async / what does await do
    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.

  9. 9
    Explain fetch and mounted
    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.

Advice: He's chill and gives you time. Questions are similar to the sheet, so practice those. Stay relaxed and be confident about your code.
  1. 1
    Vue lifecyclehooks
    Times asked 2
    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.

  2. 2
    library used for jwt 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)
  3. 3
    have u implemented search functionality
    Times asked 2
    Official solution

    SimpleSearch: form/query param → ilike filter → results template.

    Example

    q = request.args.get('q', '').strip()
    lots = Lot.query.filter(Lot.name.ilike(f'%{q}%')).all()
  4. 4
    Caching
    Times asked 4
    Official solution

    SimpleCache baar-baar DB/compute na karne ke liye result yaad rakhta hai.

    Browser cache, Flask cache, Redis. Example: dashboard counts 30 sec Redis mein.
    Cookies alag (client data). HTTP 304 Not Modified bhi cache related.
    MAD1 mein optional. Scale poochhe to pehle indexes + cache, phir extra servers.

Advice: Don't be nervous. Proctor is supportive
  1. 1
    He joined a little late around 12:06 AM and asked me the following questions:
    Times asked 2
    Official solution

    SimpleJOIN related tables ek result mein. Inner = match only; left = left side sab + match.

    Example

    db.session.query(Booking, User).join(User).filter(User.id == uid).all()
  2. 2
    i didn't had a js script which would be used to check on phone number length so he asked how u will code it, just tell me verbally so that i can get ur understanding.
    Times asked 2
    Official solution

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

  3. 3
    he also asked several celery and redis questions which is basically in many ppls feedback, u can go through that as well.
    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.

  4. 4
    then he asked what approach would be usefull Vertical scalling or horzontal scalling in order to handle millions of upcoming api calls for the booking of treks slots, then I replied that there r no perfect solutions in distributed systems its just what we want to make tradeoffs with.
    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.

  5. 5
    and then I just wasted time in demonstrating the app and giving him an idea of how i have implemented those stuffs in frontend or backend and got him impressed by me.
    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: Be calm and confident go through ur code so well that u can say about that for so looong
Maintaine By Lazy IITians Team + IITM BS students Regualr for More data you have