- add marshmallow-sqlalchemy marshmallow for inserting db data via deserialization

db/fb_models.py

@@ -0,0 +1,66 @@
+'''
+Tutorial link: https://docs.sqlalchemy.org/en/latest/orm/tutorial.html
+Sqlalchemy version: 1.2.15
+Python version: 3.7
+'''
+import os
+import datetime
+from sqlalchemy import (create_engine, Column, Integer,
+                        String, ForeignKey, Time, Date)
+from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy.orm import sessionmaker, relationship
+import sqlalchemy.orm.session
+
+Base = declarative_base()
+
+
+class Catena(Base):
+    """ catena class """
+    __tablename__ = 'CATENE'
+
+    id = Column('CHIAVE', Integer, primary_key=True)
+    name = Column('NOME', String)
+    observations = relationship('FbObservation')
+
+    def __repr__(self):  # optional
+        return f'Catena {self.name}'
+
+
+class FbObservation(Base):
+    """ FbObservation class """
+    __tablename__ = 'DATI_ACQUISITI'
+
+    # id = Column(Integer, primary_key=True)  # obligatory
+    pitch = Column('PITCH', String)
+    roll = Column('ROLL', String)
+    ora = Column('ORA', Time, primary_key=True)
+    sensore = Column('SENSORE', Integer, primary_key=True)
+    data = Column('DATA', Date)
+    temperature = Column('TEMPERATURA', String)
+
+    chiave_id = Column('CATENA', Integer, ForeignKey('CATENE.CHIAVE'))
+    catena = relationship("Catena", lazy="joined", foreign_keys=[chiave_id])
+
+    def __repr__(self):  # optional
+        return f'FbObservation {self.roll}'
+
+    @property
+    def result_time(self):
+        ''' Create a datetime object '''
+        start_datetime = datetime.datetime.combine(self.data, self.ora)
+        return start_datetime
+
+
+def create_session() -> sqlalchemy.orm.session:
+    """Return the sum of x and y."""
+    # engine = create_engine('sqlite:///:memory:')
+    db_user = os.environ.get("FDB_DBUSER")
+    db_password = os.environ.get("FDB_DBPASSWORD")
+    db_url = os.environ.get("FDB_DBURL")
+    engine = create_engine(
+         "firebird+fdb://" + db_user + ":" + db_password + "@" + db_url)
+    session_maker = sessionmaker(bind=engine)
+    session = session_maker()
+
+    Base.metadata.create_all(engine)
+    return session