Proctor Level3_19

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.

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.

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.

SimpleRBAC = Role Based Access Control. Roles (admin/user) se permissions milti hain, har user pe alag list nahi.

Example

if current_user.role != 'admin':
    flash('Not allowed')
    return redirect(url_for('user.home'))

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.

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.

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.

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.

SimpleRBAC = role ka badge. Admin badge se delete, user badge se sirf book.

Role-Based Access Control. Har user pe alag permission list nahi — roles.

Models: User M-M Role association. Decorators @roles_required. Vue v-if + router meta.

Frontend hide UX. Backend 403 real security.

Example

if current_user.roles[0].name != 'admin':
    return jsonify(msg='Forbidden'), 403

Project example: roles_users table. admin stats API roles_required. User booking POST user role.

Viva tipCode mein roles_required, Vue meta.role, models User↔Role many-to-many (roles_users table).