update

app/models/account.py

@@ -31,9 +31,7 @@ class Account(db.Model):
 
         try:
             db.session.add(account)
-            db.session.commit()
         except IntegrityError as err:
-            db.session.rollback()
             raise ValueError(f"Database integrity error: {err}")
         return account
 

app/models/customer.py

@@ -20,6 +20,13 @@ class Customer(db.Model):
         back_populates="customer",
     )
 
+    loans = relationship(
+        "Loan",
+        primaryjoin="Customer.id == Loan.customer_id",
+        foreign_keys="Loan.customer_id", 
+        back_populates="customer",
+    )
+
     @classmethod
     def is_valid_customer(cls, customer_id):
         customer = cls.query.filter_by(id=customer_id).first()
@@ -44,11 +51,20 @@ class Customer(db.Model):
                 account_type=account_type
             )
             
-            db.session.commit()
         except IntegrityError as err:
-            db.session.rollback()
             raise ValueError(f"Database integrity error: {err}")
         return customer
+    
+    @classmethod
+    def get_customer(cls, customer_id):
+        """
+        Get customer by  ID.
+        """
+        customer = cls.query.filter_by(id=customer_id).first()
+
+        if not customer:
+            raise ValueError(f"Customer does not exist")        
+        return customer
 
     def __repr__(self):
         return f'<Customer {self.id}>'

app/models/loan.py

@@ -3,6 +3,8 @@ from app.extensions import db
 from app.models.customer import Customer
 from app.models.account import Account
 from sqlalchemy.exc import IntegrityError
+from sqlalchemy.orm import relationship
+from app.models import Customer
 
 
 class Loan(db.Model):
@@ -21,6 +23,12 @@ class Loan(db.Model):
     created_at = db.Column(db.DateTime, default=datetime.now(timezone.utc))
     updated_at = db.Column(db.DateTime, default=datetime.now(timezone.utc), onupdate=datetime.now(timezone.utc))
 
+    customer = relationship(
+        "Customer",
+        primaryjoin="Customer.id == Loan.customer_id",
+        foreign_keys=[customer_id],
+        back_populates="loans",
+    )
 
     @classmethod
     def create_loan(cls, customer_id, account_id, offer_id, principal_amount, status='pending'):
@@ -47,9 +55,7 @@ class Loan(db.Model):
 
         try:
             db.session.add(loan)
-            db.session.commit()
         except IntegrityError as err:
-            db.session.rollback()
             raise ValueError(f"Database integrity error: {err}")
         return loan
 
@@ -92,8 +98,21 @@ class Loan(db.Model):
         
         # Update loan status and the updated_at timestamp
         loan.status = status
-        
-        db.session.commit()
+
+    def to_dict(self):
+        """
+        Convert the Loan object to a dictionary format for JSON serialization.
+        """
+        return {
+            'id': self.id,
+            'customer_id': self.customer_id,
+            'account_id': self.account_id,
+            'offer_id': self.offer_id,
+            'principal_amount': self.principal_amount,
+            'status': self.status,
+            'created_at': self.created_at.isoformat() if self.created_at else None,
+            'updated_at': self.updated_at.isoformat() if self.updated_at else None
+        }
     
     def __repr__(self):
         return f'<Loan {self.id}>'

app/models/offer.py

@@ -0,0 +1,16 @@
+from datetime import datetime, timezone
+from app.extensions import db
+
+class Offer(db.Model):
+    __tablename__ = 'offers'
+
+    id = db.Column(db.Integer, primary_key=True)
+    product_id = db.Column(db.String, nullable=False)
+    min_amount = db.Column(db.Float, nullable=False)
+    max_amount = db.Column(db.Float, nullable=False)
+    tenor = db.Column(db.Integer, nullable=False)
+    created_at = db.Column(db.DateTime, default=datetime.now(timezone.utc))
+    updated_at = db.Column(db.DateTime, default=datetime.now(timezone.utc), onupdate=datetime.now(timezone.utc))
+
+    def __repr__(self):
+        return f'<LoanOffer {self.id}>'

app/models/repayment.py

@@ -38,15 +38,13 @@ class Repayment(db.Model):
 
         repayment = cls(
             customer_id=customer_id,
-            loan_id=loan.id,
+            loan_id=loan_id,
             product_id=product_id,
         )
 
         try:
             db.session.add(repayment)
-            db.session.commit()
         except IntegrityError as err:
-            db.session.rollback()
             raise ValueError(f"Database integrity error: {err}")
 
         return repayment