Resolve "Age update automatically every year and DOB(Year mandatory) should be taken"

Merge Request

Overview

This MR updates the user data model by replacing the age field with date_of_birth (DOB).

The goal is to eliminate storing derived data (age) and instead store the source of truth (DOB). Age will now be dynamically calculated when required.

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What does this MR do and why?

Previously, the system stored age directly in the database. This approach caused:

• Data inconsistency over time (age becomes outdated)
• Redundant data storage
• Manual updates required to maintain accuracy

Solution

• Removed age column from the database
• Introduced date_of_birth column
• Updated backend logic to calculate age dynamically from DOB

Benefits

• Ensures accurate and up-to-date age calculation
• Follows best practice (store source, not derived data)
• Reduces data inconsistency issues

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Changes Made

Database

• Removed: age column from users table
• Added: date_of_birth (DATE type)

Backend

• Updated User model/schema
• Added utility function to calculate age from DOB
• Updated API responses to return computed age

API Changes

• Request:

  • date_of_birth added
  • age removed

• Response:

  • age is dynamically calculated and returned

Files Modified

• models/user.py
• schemas/user_schema.py
• services/user_service.py
• migrations/xxxx_add_dob_remove_age.py

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Technical Details

Root Cause

Storing age directly leads to stale data since it changes over time.

Fix

• Store date_of_birth instead
• Calculate age dynamically using current date

Example Logic

from datetime import date

def calculate_age(dob: date) -> int:
    today = date.today()
    return today.year - dob.year - (
        (today.month, today.day) < (dob.month, dob.day)
    )

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Type of Change

• ✨ New feature
• 📝 Documentation update
• 🧪 Test update
• 🔧 Configuration change

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Related Issues / References

• Closes #56 (closed)

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Screenshots

How to Validate Locally

1. Run migrations:

alembic upgrade head

2. Create a new user:

• Provide date_of_birth
• Ensure age is NOT accepted

3. Fetch user details:

• Verify age is calculated correctly

Expected Behavior

Before	After
Age stored in DB	DOB stored in DB
Age static	Age dynamic
Manual updates needed	Auto-calculated

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Testing Done

• API endpoint tests passing

Test Cases Covered

Scenario	Expected Result	Status
Create user with DOB	User created successfully	✅
Fetch user	Age calculated correctly	✅
Missing DOB	Validation error	✅

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Code Quality Checklist

Code Standards

• Code follows project conventions
• No unused code
• Type hints added

API Design

• Proper validation for DOB
• Correct HTTP responses
• API docs updated

Database & Migrations

• Migration created
• Downgrade supported
• Schema updated correctly

Security

• No sensitive data exposed
• Input validation implemented

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Documentation

• API docs updated
• .env.example unchanged

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Known Limitations / Technical Debt

• Existing users with age need migration handling (default DOB or manual update)

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Additional Notes

• This change may impact frontend forms — ensure DOB field is used instead of age input

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MR Acceptance Checklist

Quality & Correctness

• Works as expected
• No regressions

Maintainability

• Clean and readable code
• Follows best practices