Python3 Socket Server Data Model

models.py

from db import Base
from datetime import datetime
from sqlalchemy import Column, Integer, String, ForeignKey, DateTime, Boolean, Text, Float
from sqlalchemy.orm import relationship


class RadioType(Base):
    __tablename__ = 'radio_types'

    id = Column(Integer, primary_key=True)
    radio_type_name = Column(String(255), nullable=False)
    radio_type_descr = Column(String(255), nullable=False)

    def __repr__(self):
        if self.id and self.radio_type_name:
            return '{} {}'.format(
                self.id, self.radio_type_name
            )


class Radio(Base):
    __tablename__ = 'radios'

    id = Column(Integer, primary_key=True)
    radio_type = Column(Integer, ForeignKey('radio_types.id'), nullable=False)
    serial_number = Column(String(255), nullable=False)
    imei = Column(String(24), nullable=False)

    def __repr__(self):
        if self.id and self.radio_type:
            return '{} {} {}'.format(
                self.id, self.radio_type, self.imei
            )


class Tx(Base):
    __tablename__ = 'radio_txs'

    id = Column(Integer, primary_key=True)
    timestamp = Column(DateTime, nullable=False, onupdate=datetime.now)
    raw_data = Column(String(1024), nullable=False)

    def __repr__(self):
        if self.id and self.timestamp:
            return '{} {} {}'.format(
                self.id, self.timestamp, self.raw_data
            )


class TxHeader(Base):
    __tablename__ = 'radio_tx_headers'

    id = Column(Integer, primary_key=True)
    tx_id = Column(Integer, ForeignKey('radio_txs.id'), nullable=False)
    tx = relationship('Tx')
    timestamp = Column(DateTime, nullable=False, onupdate=datetime.now)
    product_type = Column(Integer, nullable=False)
    hardware_rev = Column(Float, nullable=False)
    firmware_rev = Column(String(10), nullable=False)
    contact_reason = Column(String(8), nullable=False)
    alarm_status = Column(String(8), nullable=False)
    gsm_rssi = Column(Integer, nullable=False)
    battery_status = Column(String(10), nullable=False)
    imei = Column(String(16), nullable=False)
    message_type = Column(Integer, nullable=False)
    payload_len = Column(Integer, nullable=False)

    def __repr__(self):
        if self.id:
            return '{} {} {}'.format(
                self.id, self.imei, self.message_type
            )


class TxReading(Base):
    __tablename__ = 'radio_tx_readings'

    id = Column(Integer, primary_key=True)
    tx_id = Column(Integer, ForeignKey('radio_txs.id'), nullable=False)
    tx_header_id = Column(Integer, ForeignKey('radio_tx_headers.id'), nullable=False)
    timestamp = Column(DateTime, nullable=False)
    distance = Column(Float, nullable=False, default=0.00)
    src = Column(String(255), nullable=False)
    rssi = Column(Integer, nullable=False)
    temperature = Column(Float, nullable=False)

    def __repr__(self):
        if self.id:
            return '{} {} on {}'.format(
                self.tx_id, self.distance, self.timestamp
            )