Make transaction.meter_end required and force tz utc for all datetimes

backend/app/models/transaction.py

@@ -12,7 +12,7 @@ class Transaction(Base):
     started_at = Column(DateTime, index=True)
     ended_at = Column(DateTime, nullable=True, index=True)
     meter_start = Column(Numeric(10,2))
-    meter_end = Column(Numeric(10,2), nullable=True)
+    meter_end = Column(Numeric(10,2))
     end_reason = Column(Enum(TransactionEventTriggerReason), nullable=True)
     price = Column(Numeric(10,2))
 

backend/app/schemas/auth_token.py

@@ -3,6 +3,7 @@ from datetime import datetime
 from pydantic import BaseModel
 
 from app.schemas.user import Role
+from app.util.encoders import force_utc_datetime
 
 
 @dataclass
@@ -19,3 +20,6 @@ class TokenResponse(BaseModel):
     access_token: str
     refresh_token: str
     not_after: datetime
+
+    class Config:
+        json_encoders = {datetime: force_utc_datetime}

backend/app/schemas/chargepoint.py

@@ -8,7 +8,7 @@ from app.schemas.connector import Connector
 
 from ocpp.v201.enums import ResetEnumType, ResetStatusEnumType
 
-from app.util.encoders import decimal_encoder
+from app.util.encoders import decimal_encoder, force_utc_datetime
 
 class ChargePointBase(BaseModel):
     identity: str
@@ -34,7 +34,7 @@ class ChargePoint(ChargePointBase):
 
     class Config:
         from_attributes = True
-        json_encoders = {Decimal: decimal_encoder}
+        json_encoders = {Decimal: decimal_encoder, datetime: force_utc_datetime}
 
 class ChargePointThumb(BaseModel):
     id: UUID

backend/app/schemas/meter_value.py

@@ -5,7 +5,7 @@ from typing import Optional
 from uuid import UUID
 from pydantic import BaseModel
 
-from app.util.encoders import decimal_encoder
+from app.util.encoders import decimal_encoder, force_utc_datetime
 
 class PhaseType(enum.Enum):
     L1 = "L1"
@@ -57,4 +57,4 @@ class MeterValue(BaseModel):
 
     class Config:
         from_attributes = True
-        json_encoders = {Decimal: decimal_encoder}
+        json_encoders = {Decimal: decimal_encoder, datetime: force_utc_datetime}

backend/app/schemas/session.py

@@ -2,6 +2,8 @@ from datetime import datetime
 from uuid import UUID
 from pydantic import BaseModel
 
+from app.util.encoders import force_utc_datetime
+
 
 class Session(BaseModel):
     id: UUID
@@ -9,4 +11,5 @@ class Session(BaseModel):
     last_used: datetime
 
     class Config:
-        from_attributes = True
+        from_attributes = True
+        json_encoders = {datetime: force_utc_datetime}

backend/app/schemas/transaction.py

@@ -6,7 +6,7 @@ from pydantic import BaseModel
 
 from app.schemas.chargepoint import ChargePointThumb
 from app.schemas.user import UserThumb
-from app.util.encoders import decimal_encoder
+from app.util.encoders import decimal_encoder, force_utc_datetime
 
 class TransactionStatus(enum.Enum):
     ONGOING = "ongoing"
@@ -45,7 +45,7 @@ class Transaction(BaseModel):
     started_at: datetime
     ended_at: Optional[datetime] = None
     meter_start: Decimal
-    meter_end: Optional[Decimal] = None
+    meter_end: Decimal
     end_reason: Optional[TransactionEventTriggerReason] = None
     price: Decimal
     user: UserThumb
@@ -53,7 +53,7 @@ class Transaction(BaseModel):
 
     class Config:
         from_attributes = True
-        json_encoders = {Decimal: decimal_encoder}
+        json_encoders = {Decimal: decimal_encoder, datetime: force_utc_datetime}
 
 class RemoteTransactionStartStopResponse(BaseModel):
     status: RemoteTransactionStartStopStatus

backend/app/services/transaction_service.py

@@ -21,19 +21,23 @@ async def create_transaction(
     with SessionLocal() as db:
         chargepoint = db.query(ChargePoint).filter(ChargePoint.identity == chargepoint_identity).first()
         meter_start=0
+        meter_end=0
         if "meter_value" in transaction_data.keys():
             for meter_value_entry in transaction_data['meter_value']:
                 for sampled_value in meter_value_entry['sampled_value']:
                     if "measurand" in sampled_value.keys():
                         if sampled_value['measurand'] == str(Measurand.ENERGY_ACTIVE_IMPORT_REGISTER):
                             meter_start = sampled_value['value']
+                            meter_end = sampled_value['value']
                     else:
                         meter_start = sampled_value['value']
+                        meter_end = sampled_value['value']
         transaction = Transaction(
             id=transaction_info["transaction_id"],
             status=TransactionStatus.ONGOING,
             started_at=timestamp,
             meter_start=meter_start,
+            meter_end=meter_end,
             price=chargepoint.price,
             chargepoint_id=chargepoint.id,
             user_id=user_id
@@ -55,6 +59,12 @@ async def update_transaction(
                             transaction_id=transaction.id,
                             meter_value_data=meter_value_entry
                         )
+                        # Update current meter_end value
+                        for sampled_value in meter_value_entry['sampled_value']:
+                            if "measurand" in sampled_value.keys():
+                                if sampled_value['measurand'] == str(Measurand.ENERGY_ACTIVE_IMPORT_REGISTER):
+                                    transaction.meter_end = sampled_value['value']
+                                    db.commit()
                         
 async def end_transaction(
     transaction_id: str,

backend/app/util/encoders.py

@@ -1,3 +1,4 @@
+from datetime import datetime, timezone
 from decimal import Decimal
 from typing import Union
 
@@ -19,4 +20,8 @@ def decimal_encoder(dec_value: Decimal) -> Union[int, float]:
     if isinstance(exponent, int) and exponent >= 0:
         return int(dec_value)
     else:
-        return float(dec_value)
+        return float(dec_value)
+    
+def force_utc_datetime(datetime_value: datetime) -> datetime:
+    """Force a datetime to be in the UTC timzone"""
+    return datetime_value.replace(tzinfo=timezone.utc)