Lazy IITians – Viva Prep

See reviews Level2_131 MAD1 Level 2

Aug 14, 2026

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1

Explain the Vue Lifecycle

Times asked 1

Official solution

SimpleCode explain formula: input kya aaya → auth/validation → DB change → response/UI.
Viva tipFunction signature + 3-4 important lines + edge case.
2
What is the use of 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.

Advice: Examiner is very good and patient, clearly explains his questions No mobile joining for level 1

See reviews Level2_132 MAD1 Level 2

Aug 14, 2026

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1

Level 1

Times asked 12

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

He is very chill , first I downloaded from portal

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
3
Then run app

Times asked 2
Official solution

Simpleapp = Flask(__name__) app banata hai; if __name__ == '__main__' tabhi server start jab file directly run ho.
```
app = Flask(__name__)
if __name__ == '__main__':
    app.run(debug=True, port=5000)
```
__name__ module ka naam. Direct run pe '__main__', import pe filename. Import karoge to server auto-start nahi — tests/blueprints ke liye zaroori.
debug=True: auto-reload + debugger. Production mein band rakho (security).
Port: app.run(port=8000) ya flask run --port 8000. Default 5000. Haan, change ho sakta hai.
4

After proctor ask some questions

Times asked 2

Official solution

SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.
5
What is celery where you use

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.
6

Where you implement api

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.
7
Diffence Put vs patch

Times asked 2
Official solution

SimplePOST naya janam (har baar naya id). PUT poori photo replace. PATCH sticker chipkao.
POST create, not idempotent. PUT full update, idempotent. PATCH partial.
POST ki jagah PUT se REST semantics toot. GET typically no body.
CRUD map: POST create, GET read, PUT/PATCH update, DELETE delete.
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
```
POST /api/venues
PUT  /api/venues/1   {all fields}
PATCH /api/venues/1 {only name}
```
Project example: POST /api/venues create. PUT /venues/1 saari fields. PATCH sirf name.
8

Css inline vs intenal vs external

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.
9
He ask questions in conversation

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

Overall good experience

Times asked 2

Official solution

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

Advice: Learn theory.

See reviews Level1_94 MAD1 Level 1

Aug 14, 2026

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1

Level 1 Viva by level 1_94

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
Question- Show me full Project, focus on celery running or not, explain how celery works ,

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.
3
Three 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'))
```
4
- change code to show all users data

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
- My monthly report was not running so fix that

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
- check APIs through thunder client etc

Times asked 2
Official solution

SimpleAPI = interface jisse systems baat karein. Web API usually JSON return karti hai.
Example
```
@app.route('/api/lots')
def api_lots():
    return jsonify([{'id': l.id, 'name': l.name} for l in Lot.query.all()])
```
7
- show if cookies are being made in browser

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().
8

Not chill proctor, viva was about 55 mins.

Times asked 2

Official solution

SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.
9

Theory:-

Times asked 4

Official solution

SimpleTheory = concepts: ORM, MVC, auth vs authz, Jinja inheritance, sessions. 1-line def + project example.
10
Client vs distributed network

Times asked 4
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
```

<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.
11
Cell spaceing vs cell padding

Times asked 4
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.
12
What is ORM explain

Times asked 1
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
```
13
Explain full code of models.py

Times asked 3
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)
```
14
What is db.model

Times asked 2
Official solution

Simpledb Flask-SQLAlchemy ka object hai. Models db.Model se inherit karti hain, tables db.create_all() se banti hain.
db = SQLAlchemy()
db.init_app(app) # factory pattern
```
with app.app_context():
    db.create_all()

db.Model SQLAlchemy declarative base (class). Columns se table schema.
```
db properties engine/session/metadata se aati hain, Flask app config (SQLALCHEMY_DATABASE_URI) se bind.
Admin user: create_all sirf tables; admin seed alag function mein (if not User.query.filter_by(role='admin').first(): ...).
Live schema change: Flask-Migrate/Alembic. create_all nayi tables add kare, existing columns alter nahi karta generally.
15

If some new booking happens how the apis and routes are working together explain process

Times asked 4

Official solution

SimpleNayi booking flow: UI form/button → route POST → login_required → validate seats → insert Booking → commit → redirect/flash.
Suggested flowBrowser → Flask route → Auth → Business rules → SQLAlchemy → SQLite → Response template/JSON
16

Difference between back populate and back ref

Times asked 4

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.
17

Coding:-

Times asked 2

Official solution

SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.
18

Change button color

Times asked 1

Official solution

Simpleexaminer UI tweak maangta hai — CSS class ya inline, instantly dikhao.
Button color: <button class='btn btn-success'> ya style='background:#22c55e;color:#fff'
Navbar: navbar-dark bg-success / style='background:yellow' / fixed-bottom se neeche.
Center: .wrap { display:flex; justify-content:center; align-items:center; min-height:100vh; }
text-align:center heading ke liye. Bootstrap: d-flex justify-content-center, mx-auto, text-center.
Hover: .btn:hover { opacity:0.8; transform:scale(1.02); }
Half width: class='col-6' ya width:50%. Row→column: flex-direction:column / col-12 stack.
Login card: card shadow p-4 mx-auto (max-width:400px).
Table header green: th { background:green; color:white; } Bold column: td:nth-child(2){font-weight:bold}
Box shadow: box-shadow: 4px 4px 12px rgba(0,0,0,.3);
Background image: body { background: url('/static/bg.jpg') center/cover; }
Reset button: <button type='reset'>Clear</button>
Move button: ms-auto / position / flex order.
Jinja dashboard heading: <h1>{{ user.name }}'s Dashboard</h1>
19
Put sign up button to right side

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.
20

Show me all users data (just thought process)

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.
21

Super chill proctor patient and will help you as well, be confident and if you don't know something just say no don't mug up

Times asked 2

Official solution

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

Advice: Level1_94 May God save you Level3_25 super chill you are in good hands, be confident you ar going to get marks, just learn how to check APIs in thunderclient he might ask it.

See reviews Level3_24 MAD1 Level 3

Aug 14, 2026

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1

Showing the 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.
2

Showcasing the app entirely, all the core functionalities that you can remember.

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
Q3:what are the ways in which we can store data in the client side.

Times asked 2
Official solution

Simpledata() local diary. Store school notice board.
Search query local. Logged-in user store. Persist: store + localStorage together.
state vs data: similar concept, scope alag.
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
```
// local
data() { return { q: '' } }
// global
this.$store.state.user
```
Project example: Login.vue local form fields. this.$store.state.user Navbar.
4

And maybe I was lucky he didnt ask to make changes in the code just regular ones like changing order and frontend coloring of background or text.

Times asked 2

Official solution

SimpleMAD1 frontend usually Jinja templates + HTML/CSS/Bootstrap (+ thoda JS). MAD2 pe Vue ho to clearly bolo.
5
Rating your MAD2 Project out of 5

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.

Advice: The proctor is very Professional, even if you dont know answer just say I'm not able to recall it right now, He is a very calm and chill but some might consider him rude by his tone but If you are fluent with your words, he will be nice to you. Just answer everything honestly.

See reviews Level2_148 MAD1 Level 2

Aug 14, 2026

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1

demo

Times asked 12

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

what are the problems u faced while making the app

Times asked 2

Official solution

SimpleChallenges honestly: relationships/cascade, session bugs, overbooking race, CSS layout, deploy. Seekha kya — woh bold karo.
3

if i give u more time, what vl u improve about the app

Times asked 2

Official solution

SimpleImprove ideas: caching, better validation, tests, pagination, email reminders, accessibility, mobile UI, logging.
Viva tip1-2 concrete features bolo jo time milne pe add karte — vague 'AI' mat.
4

if u had to scale the app to 10000+ users, what changes will u do

Times asked 2

Official solution

Simple10k users: Postgres, caching, celery workers, pagination, indexes, load balancer, no SQLite write contention.
5

if u were taking this app to the next level as a startup and making it a proper product, what changes will u make?

Times asked 2

Official solution

SimpleImprove ideas: caching, better validation, tests, pagination, email reminders, accessibility, mobile UI, logging.
Viva tip1-2 concrete features bolo jo time milne pe add karte — vague 'AI' mat.
6

asked to show code where i am doing try ... catch while fetching from api. asked to demonstrate any situation where error will occur and show the error message being displayed

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

how did u test this app, how can u be 100% sure that it will work in all cases? didnt ask me to make any code changes, just tested thought process. overall went very well.

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: very friendly examiner. just answer honestly, itll go great

See reviews Level2_101 MAD1 Level 2

Aug 14, 2026

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1

Went on for 45 minutes in depth (cause I kept answering and used terminology)

Times asked 2

Official solution

SimpleViva wrap-up hai. Short thanks + confirm submission ZIP latest hai.
2

Basic Things - ID card, github, download, checksum, run

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

Explain all the features implemented in the application (Showcase 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.
4
What is pagination and why used

Times asked 1
Official solution

SimplePagination badi list ko pages mein todta hai — offset/limit ya Flask-SQLAlchemy paginate().
Example
```
page = request.args.get('page', 1, type=int)
pagination = Lot.query.paginate(page=page, per_page=10)
```
5
What are vue directives

Times asked 3
Official solution

SimpleDirectives Vue ke special attributes — HTML ko superpower.
v-if/else/show, v-for, v-bind (:), v-on (@), v-model, v-html (XSS), v-cloak, v-slot.
:src = v-bind:src. @click = v-on:click.
Custom directives bhi (v-focus) — course basics kaafi.
Example
```
<p v-if="ok">Yes</p>
<li v-for="u in users" :key="u.id">{{ u.name }}</li>
<input v-model="email">
<img :src="url">
```
Project example: List v-for :key. Form v-model. Admin v-if. Image :src.
Viva tip: src ke liye v-bind:src ka shorthand. @click = v-on:click.
6

What are lifecycle hooks

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.
7
What is SMTP & what port are you using and what is the default

Times asked 2
Official solution

SimpleSMTP = email bhejne ka protocol, jaise HTTP web ka.
Ports: 587 STARTTLS, 465 SMTPS, 25 server-server. Dev: MailHog 1025.
Flask-Mail wrap. Sync send slow — Celery task se bhejo.
Fayda: universal. Nuksaan: spam, deliverability (SPF/DKIM), no guarantee like API.
Example
```
app.config['MAIL_SERVER'] = 'localhost'
app.config['MAIL_PORT'] = 1025
mail.send(Message('Hi', recipients=['a@b.com'], body='Hello'))
```
Project example: MAIL_SERVER=localhost MAIL_PORT=1025. Production later SendGrid/SES.
Viva tipFayda: universal. Nuksaan: deliverability, spam, sync send slow — isliye Celery + MailHog in dev.
8
Default port for flask

Times asked 2
Official solution

SimpleFlask lightweight Python web framework — routes, request/response, templates. MAD1 ka backend yahi hai.
Example
```
from flask import Flask
app = Flask(__name__)

@app.route('/')
def home():
    return 'Hello'
```
Viva tipFlask micro hai: jo chahiye (DB, login, forms) khud jodte ho.
9
Explain the model and why used in such way

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)
```
10
Explain Primary key (went into depth as to why use primary key instead of just nullable and unique with indexing)

Times asked 2
Official solution

SimplePrimary key row ka unique identity — usually id Integer autoincrement.
Example
```
id = db.Column(db.Integer, primary_key=True)
```
11
Joins in databases

Times asked 1
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()
```
12
Explain python decorators

Times asked 2
Official solution

Simplelogin_required jaisa decorator protected routes pe: session nahi to login redirect.
Example
```
def login_required(fn):
    @wraps(fn)
    def wrapper(*a, **k):
        if 'user_id' not in session:
            return redirect(url_for('auth.login'))
        return fn(*a, **k)
    return wrapper
```
13
What is jsonify

Times asked 1
Official solution

Simplejsonify Python dict/list ko JSON response + proper Content-Type deta hai.
Example
```
return jsonify(message='ok', count=3), 200
```
14
Different codes returned by flask / endpoints

Times asked 2
Official solution

SimpleFlask lightweight Python web framework — routes, request/response, templates. MAD1 ka backend yahi hai.
Example
```
from flask import Flask
app = Flask(__name__)

@app.route('/')
def home():
    return 'Hello'
```
Viva tipFlask micro hai: jo chahiye (DB, login, forms) khud jodte ho.
15
What are props

Times asked 2
Official solution

SimpleProps parent ki thali child ko dena. Child thali tod ke parent ki thali na badle — emit bolo.
Declare props, parent :venue="v". One-way. Mutate mat. Types/required Vue 3.
List parent, card child — classic viva.
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
```
<VenueCard :venue="v" @select="onSelect" />
props: ['venue']
this.$emit('select', this.venue.id)
```
Project example: VenueCard :venue. Child $emit('select', id).
16
Diff bw props & slots

Times asked 2
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.
17
Why used async majorly in the project

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.
18
What router was used and why do we use different routers instead of browser working

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.
19

Show the celery jobs

Times asked 1

Official solution

SimpleTask function, beat dict, delay() call, worker+beat terminals, MailHog/CSV.
App context DB. Args serializable. How many jobs: reminder, monthly, export — gino honestly.
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: tasks.py + config schedule + POST export.
20

What is the process of the data flow in these jobs

Times asked 2

Official solution

SimpleNayi booking flow: UI form/button → route POST → login_required → validate seats → insert Booking → commit → redirect/flash.
Suggested flowBrowser → Flask route → Auth → Business rules → SQLAlchemy → SQLite → Response template/JSON
21
What will happen if the load was multiplied by millions

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.
22
Change the priority essentially

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.
23

What is webhooks

Times asked 1

Official solution

SimpleCode explain formula: input kya aaya → auth/validation → DB change → response/UI.
Viva tipFunction signature + 3-4 important lines + edge case.
24

how are they different

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.
25

How does websockets work

Times asked 1

Official solution

SimpleCode explain formula: input kya aaya → auth/validation → DB change → response/UI.
Viva tipFunction signature + 3-4 important lines + edge case.
26

How would you scale the application to be used by millions of users

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.
27
What fallback have you implemented to make sure the data is not leaked

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.
28
What is cached when you use the cache.cached decorator

Times asked 1
Official solution

Simplelogin_required jaisa decorator protected routes pe: session nahi to login redirect.
Example
```
def login_required(fn):
    @wraps(fn)
    def wrapper(*a, **k):
        if 'user_id' not in session:
            return redirect(url_for('auth.login'))
        return fn(*a, **k)
    return wrapper
```

Advice: The proctor was chill and majorly went into depth because I kept giving answers in detailed and we basically talked a lot about how the inner workings for a lot of databases and apis. If you know you can go into detail while answering but only if you know do this otherwise you might go blank as to what the person is asking.

See reviews LEVEL1_viva14 MAD1 Level 1

Aug 14, 2026

Download all Download all

Copy set link

1

level1_viva_14

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

Show me your 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

Show me the 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

It didn't match so just downloaded directly from the portal and start showing the demonstration of all the functionalities that you have in your application

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
5
Where is token store

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.
6
what is the difference between authentication and authorisation

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)
```
7

What is caching?

Times asked 23

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.
8
What you have implemented for 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)
```
9

How you have define the role base access show me the code for each user excess control.

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.
10
Do you have said the token expiration time if yes what is it?

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.
11

Show the working for email notification for the scheduled task

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.
12

Show me the backend API routes

Times asked 1

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.
13

How much percentage of AI you have used in your application ? Did you mention that in your report too

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.
14

Also he has seen the API routes where i hv mentioned in my report....

Times asked 2

Official solution

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

Advice: I made feature full application so it took me around 50 minutes for the level one Viva there some other small rapid fire questions that I'm not able to recall right now and also I didn't get the transcript yet so this is all that I remember till now... About proctor is a polite and kind guy he won't interrupt you whenever you are showing your demo or explaining some section he is a keen listener who will try to digest everything you are saying very deeply, calmly with no hurry and then ask the question based on that... Just be confident and trust ur preparation...rest everything will go well

See reviews APPDEV_LEVEL1_VIVA3 MAD1 Level 1

Aug 14, 2026

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1
Have you implemented session-based or token-based authentication?

Times asked 3
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().
2
Where is the token stored?

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
Purpose of token-based authentication / why do we need a token?

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)
```
4

How to maintain referential integrity between tables?

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
What is a foreign key?

Times asked 3
Official solution

SimpleForeign key dusri table ke PK ko point karti hai — relationship banati hai.
Example
```
lot_id = db.Column(db.Integer, db.ForeignKey('lot.id'), nullable=False)
```
6
If parent row is deleted, what happens to child rows?

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.
7
What if ON DELETE CASCADE is not used?

Times asked 2
Official solution

SimpleCascade parent delete pe children pe kya ho: delete-orphan related rows hata deta hai.
Example
```
db.relationship('Spot', cascade='all, delete-orphan')
```
Viva tipParking lot delete → uske spots/bookings policy clear bolo.
8

Have you created backend APIs?

Times asked 3

Official solution

SimpleYes REST. List 5. Postman. Local APIs vs REST: MAD2 REST JSON.
Did you create backend APIs? Yes examples.
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: resources.py.
Project example: resources.py.
9
Which tool used for caching (Redis)?

Times asked 2
Official solution

SimpleRedis fridge pe sticky note hai — poori kitchen (database) kholne ki zarurat nahi.
Redis in-memory key-value store hai. Data RAM mein rehta hai, isliye disk wale SQLite/Postgres se kai guna tez.
MAD2 mein Redis do kaam karta hai:
1) Cache — same venue/show/dashboard JSON baar-baar DB se mat nikaalo.
2) Celery message broker — Flask task queue mein daalta hai, worker uthata hai.
Source of truth database hi hai. Redis band ho to cache miss ho jaata hai aur Celery queue ruk sakti hai. Crash pe cache gayab ho sakta hai — isliye important data sirf Redis mein mat rakho.
Example
```
import redis
r = redis.Redis(host='localhost', port=6379, db=0)
r.set('venues', json.dumps(data), ex=30)
print(r.get('venues'))
```
Project example: GET /api/venues pehle Redis dekho. Miss pe SQLAlchemy query, phir SET with timeout. Celery worker Redis list se daily reminder uthata hai.
Viva tipCache ke liye db=1, broker ke liye db=0 rakhna smart hai taaki keys mix na hon. Viva mein redis-cli ping → PONG dikhana strong hai.
10
Show where cached data is stored?

Times asked 2
Official solution

Simpledata() local diary. Store school notice board.
Search query local. Logged-in user store. Persist: store + localStorage together.
state vs data: similar concept, scope alag.
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
```
// local
data() { return { q: '' } }
// global
this.$store.state.user
```
Project example: Login.vue local form fields. this.$store.state.user Navbar.
11

Show me where admin is created in the application?

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.
12

Difference between v-if and v-show?

Times asked 2

Official solution

Simplev-if element DOM se hataata/jodata hai, v-show sirf CSS display toggle karta hai.
v-if='isAdmin' → false ho to element exist hi nahi. Costly toggle, lekin hidden data DOM mein nahi.
v-show='open' → display:none. Fast toggle, element hamesha DOM mein.
Rare condition: v-if. Bar-bar toggle (dropdown): v-show.
13
What is ORM?

Times asked 49
Official solution

SimpleORM = Object Relational Mapping. Database tables ko Python classes/objects se map karta hai, raw SQL kam likhni padti hai.
Bina ORM: cursor.execute('SELECT * FROM user WHERE id=?', [5])
ORM se: User.query.get(5) ya db.session.get(User, 5)
Example model
```
class User(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    email = db.Column(db.String(120), unique=True)
```
FaydePython mein soch sakte ho, SQL injection se protection (parameterized), relationships easy, DB switch thoda aasan.
Nuksaancomplex queries slow/abstract, seekhne ki layer extra, kabhi raw SQL phir bhi chahiye.
MAD1: SQLAlchemy (Flask-SQLAlchemy). Tables db.create_all() ya migrations se banti hain.
14

Use of anchor tag?

Times asked 2

Official solution

SimpleHTML structure, CSS styling. Templates mein semantic tags + classes. Responsive ke liye viewport + flex/grid/bootstrap.

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