Allen batch scheduler

Functional Requirements:

1. Operator should be able to schedule batch for students
2. User can be present in multiple batch
3. Batch should not be conflicting, with other batch if user is common in 2 batch, and should show conflict before booking
4. Student should be able to fetch list of batch for given month or week range only for his enrolled batch
5. User should be able to see all scheduled batch for given date range
6. Same batch should not be scheduled for the same time slot twice
7. Schedule batch only for future dates
8. All student should receive notification for new scheduled batch
9. All enrolled student should get notification before 30 min of the class
10. Operator can see available free slot for given batch and date.
11. batch can be recurring
12. batch can be scheduled for any time duration

NFR:

1. Data should not get lost
2. Read latency should be minimal
3. Its a read heavy system
4. concurrency should be handled

Capacity estimates:

Read : 10K / Sec Write: 10/Sec Batches count: 20K all across country

Tables schema

`User

id	name	age	Role
U1	U1 name	18	Student
U2
U10			Operator

`Batch

Id	name	description	tag
B1	B1-name	des	Math
B2			Physics
B3			Chemistry

`User Batch

Id	user Id	batch Id	active	created at
1	U1	B1
	U2	B1
	U3	B1
	U4	B1
	U1	B2
	U5	B2
	U6	B3

`Batch Schedule

Id	start time	end time	batch Id	isRecurring	recurring pattern
BS1	14/02/2025 10:00 AM	14/02/2025 11 AM	B1		{}

User Schedule

id	user Id	start time	end time	batch schedule id
	U1	10:00	11:00 AM	BS1

`+ve scenario

B1 has to be scheduled for 14/02/2025 from 10AM to 11 AM

-ve scenario B2 has to be scheduled for 14/02/2025 from 10AM to 11 AM after B1 is scheduled