sqla-wrapper 4.200628

A framework-independent wrapper for SQLAlchemy that makes it really easy to set up.

SQLA-wrapper

A friendly wrapper for SQLAlchemy.

Why?

SQLAlchemy is great, but can be difficult to set up. With SQLA-Wrapper you can quickly start like:

from sqla_wrapper import SQLAlchemy

db = SQLAlchemy('sqlite:///:memory:')

class User(db.Model):
    __tablename__ "users"
    id = db.Column(db.Integer, primary_key=True)
    ...

db.create_all()
todos = db.query(User.id, User.title).all()

instead of having to write something like:

# Who's going to remember all of this?
from sqlalchemy import create_engine
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker, Column, Integer

engine = create_engine('sqlite:///:memory:')
Session = sessionmaker(bind=engine)
session = Session()
Model = declarative_base()

class User(Model):
    __tablename__ "users"
    id = Column(Integer, primary_key=True)
    ...

Model.metadata.create_all(engine)
session = Session()
todos = session.query(User).all()

Installation

Install the package using Pypi:

python -m pip install sqla-wrapper

Basic usage

from sqla_wrapper import SQLAlchemy

db = SQLAlchemy('sqlite:///:memory:')

class User(db.Model):
    __tablename__ "users"
    id = db.Column(db.Integer, primary_key=True)
    ...

db.create_all()

db.add(User(...))
db.commit()

todos = db.query(User).all()

Compared to SQLAlchemy

Compared to plain SQLAlchemy, you need to know that:

The SQLAlchemy gives you access to the following things:

• All the functions and classes from sqlalchemy and sqlalchemy.orm
• All the functions from a preconfigured scoped session (called _session).
• The ~SQLAlchemy.metadata and ~SQLAlchemy.engine
• The methods SQLAlchemy.create_all and SQLAlchemy.drop_all to create and drop tables according to the models.
• A Model baseclass that is a configured declarative base. This model has a few utility methods:

class Model(Object):
    @classmethod
    def exists(cls, **attrs):
        """Returns whether an object with these attributes exists."""

    @classmethod
    def create(cls, **attrs):
        """Create and persist a new record for the model."""

    @classmethod
    def create_or_first(cls, **attrs):
        """Tries to create a new record, and if it fails
        because already exists, return the first it founds."""

    @classmethod
    def first(cls, **attrs):
        """Returns the first object found with these attributes."""

    def save(self):
        """Saves the updated model to the current entity db and commits."""

    def delete(self):
        """Removes the model from the current session and commits."""

This model class also generates a default repr for your models, based on their class names an primary keys.