Viva Prep

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

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

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

SimpleJinja2 Flask ka template engine — HTML ke andar {{ }} variables, {% %} logic.

Example

{% for lot in lots %}
  <li>{{ lot.name }} — {{ lot.spots }}</li>
{% else %}
  <p>No lots</p>
{% endfor %}

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

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.

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

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.

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

Viva tip1 minute elevator pitch ready rakho, phir demo.

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.

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.

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.

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)

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.

SimpleLogin token create. Decorators protected APIs. JWT/Security init factory.

Where JWT authentication implemented backend. Show auth code.

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

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

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

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

Project example: auth.py + decorators.

SimpleCelery background tasks (email, CSV, reports) async chalaata hai. Redis broker/queue + cache.

User 'Export' click → Celery task queue → Redis message → worker CSV banaata hai → user baad mein download.
Saath isliye: Celery ko broker chahiye, Redis tez in-memory. MAD2 topic zyada, MAD1 mein optional.
Priority: task queues/routing. Caching: Redis mein key-value, DB hits kam.
Pub/Sub: publisher channel pe message, subscribers sunte hain — Redis yeh bhi karta hai.

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

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.

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.

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.

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

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

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

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

Example

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

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

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

SimpleDOM = Document Object Model — HTML ka tree jo browser memory mein banata hai. JS isi ko change karta hai.

document.getElementById('btn').style.color = 'red'
Jinja server pe HTML banata hai, phir browser DOM parse karta hai. Vue DOM ko reactive update karta hai.

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

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

Simplewindow.localStorage key-value strings origin persist. Advantages: persist 5MB simple. Nuksaan XSS no expiry strings.

What is Local Storage. Advantages.

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: setItem token.

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.

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