Consultant Calendar API

Overview

A Django REST API system that manages consultant availabilities and bookings. The system enables consultants to set their availability slots (both one-time and recurring) and allows users to book appointments.

Table of Contents

• Models
• API Endpoints
• Testing
• Development Setup
• Production Considerations

Models

Core Models

User

• Basic user model for customers who can book consultations

class User(models.Model):
    first_name = models.CharField(max_length=50)
    last_name = models.CharField(max_length=50)

Consultant

• Represents service providers

class Consultant(models.Model):
    first_name = models.CharField(max_length=50)
    last_name = models.CharField(max_length=50)

Availability

• Single time slots for consultants

class Availability(models.Model):
    consultant = models.ForeignKey(Consultant, on_delete=models.CASCADE)
    start_time = models.TimeField()
    end_time = models.TimeField()
    date = models.DateField()
    is_booked = models.BooleanField(default=False)

RecurringAvailability

• Weekly patterns for consultant availability

class RecurringAvailability(models.Model):
    DAYS_OF_WEEK = [
        (0, 'Monday'),
        (1, 'Tuesday'),
        (2, 'Wednesday'),
        (3, 'Thursday'),
        (4, 'Friday'),
        (5, 'Saturday'),
        (6, 'Sunday')
    ]
    consultant = models.ForeignKey(Consultant, on_delete=models.CASCADE)
    day_of_week = models.IntegerField(choices=DAYS_OF_WEEK)
    start_time = models.TimeField()
    end_time = models.TimeField()
    is_active = models.BooleanField(default=True)

Booking

• Links users with availabilities

class Booking(models.Model):
    availability = models.OneToOneField(Availability, on_delete=models.CASCADE)
    user = models.ForeignKey(User, on_delete=models.CASCADE)

Design Decisions

1. Separate User and Consultant Models

   • Clear separation of roles
   • Independent model evolution
   • Distinct attributes and behaviors

2. Dual Availability Models

   • Availability: Single slots for flexibility
   • RecurringAvailability: Patterns for convenience
   • Optimized querying for each use case

3. Independent Booking Model

   • Better than simple flag on Availability
   • Supports booking metadata
   • Easier historical tracking
   • Extensible for future features

API Endpoints

Consultant Management

POST /consultant/ 
GET /consultant/<id>/

Availability Management

POST /consultants/<id>/availabilities/    # Create slot
GET /consultant/<id>/availability/        # Get slots
GET /consultants/availabilities/<date>/   # Daily view
DELETE /consultant/<id>/availability/     # Remove slot

Recurring Availability

POST /consultant/<id>/recurring/          # Set pattern
GET /consultant/<id>/recurring/           # View patterns

Booking

POST /consultant/<id>/reserve/            # Book slot

Calendar Views

GET /availabilities/monthly/              # Monthly view
GET /availabilities/timerange/            # Date range view

Testing

Current Test Coverage

class ConsultantAvailabilityTests(APITestCase):
    def setUp(self):
        # Setup test data
        self.consultant = Consultant.objects.create(
            first_name="Test",
            last_name="Consultant"
        )
        
    def test_create_availability(self):
        # Test availability creation
        pass

    def test_get_availability(self):
        # Test availability retrieval
        pass

Test with CURL

1. Create Entities

# Create consultant
curl -X POST http://localhost:8000/consultant/ \
  -H "Content-Type: application/json" \
  -d '{
    "first_name": "John",
    "last_name": "Doe"
  }'

# Create user
curl -X POST http://localhost:8000/user/ \
  -H "Content-Type: application/json" \
  -d '{
    "first_name": "Jane",
    "last_name": "Smith"
  }'

2. Manage Availability

# Create availability
curl -X POST http://localhost:8000/consultants/1/availabilities/ \
  -H "Content-Type: application/json" \
  -d '{
    "date": "2024-12-25",
    "start_time": "09:00:00",
    "end_time": "10:00:00"
  }'

# Get consultant's availability
curl -X GET http://localhost:8000/consultant/1/availability/

Production Considerations

Database Optimization

Indexing

# Add to models.py
class Availability(models.Model):
    class Meta:
        indexes = [
            models.Index(fields=['consultant', 'date', 'is_booked']),
            models.Index(fields=['date', 'is_booked']),
        ]

Query Optimization

• Use select_related() for foreign keys
• Implement pagination
• Cache frequent queries
• Use database connection pooling

Development Setup

Prerequisites

• Python 3.8+
• Django 4.0+

Installation

# Clone repository
git clone [repository-url]

# Install dependencies
pip install -r requirements.txt

# Run migrations
python manage.py migrate

# Start development server
python manage.py runserver