PostgreSQL introspection to API - some automation experiments

__init__.py

# Make this folder import-able.

app.py

"""A RESTFUL API for {{ cookiecutter.app }}."""

from flask import Flask
from flask.ext.migrate import Migrate, MigrateCommand
from flask.ext.script import Manager
import flask_restless
from flask_restful import Api

# First-party
import models
from sessions import SESSION, ENGINE

app = Flask('{{ cookiecutter.app }}')
app.debug = bool({{ cookiecutter.app }})
api = Api(app)
manager = flask_restless.APIManager(app, session=SESSION)

# Setup Migrations
migrate = Migrate(app, ENGINE)

# Setup script Manager
script_manager = Manager(app)
script_manager.add_command('db', MigrateCommand)

api_options = dict(
    methods=['GET', 'POST', 'PATCH', 'DELETE', 'PUT'],
    results_per_page=100,
)

# Create API endpoints, which will be available at /api/<tablename> by
# default. Allowed HTTP methods can be specified as well.
# Create the Flask-Restless API manager.
{% for model in cookiecutter.models %}
manager.create_api(models.{{ model }}, **api_options)
{% endfor %}

if __name__ == '__main__':
    script_manager.run()

config_maker.py

import json

from sqlalchemy.ext.declarative.api import DeclarativeMeta

import models

invalid = ['Base']

jsonconfig = dict(
    app='myapp',
    db='postgresql://user:pass@0.0.0.0:5432/mydb',
    debug=True,
    models=list(set([obj.__name__ for k, obj in globals().items() if isinstance(obj, DeclarativeMeta) and obj.__name__ not in invalid]))
)

with open('cookiecutter.json', 'wb') as config:
    config.write(json.dumps(jsonconfig, indent=4))

cookiecutter.json

{
  "app": "myapp",
  "debug": true,
  "db_uri": "postgresql://user:pass@0.0.0.0:5432/mydb"
}

magical.sh

pip install sqlacodegen
pip install cookiecutter
pip install flask-restless

sqlacodegen postgresql://user:pass@0.0.0.0:5432/mydb > models.py

# Generate the cookiecutter json
python config_maker.py

# Assuming this is the folder where the actual python files/cookiecutter code lives.
cookiecutter myflask-app

sessions.py

"""Session setup for accessing models for {{ cookiecutter.app }}"""

from __future__ import absolute_import
from contextlib import contextmanager
import os

from sqlalchemy import create_engine
from sqlalchemy.orm import scoped_session, sessionmaker

DB_URI = '{{ cookiecutter.db_uri }}'
ENGINE = create_engine(DB_URI, echo=bool('{{ cookiecutter.debug }}'))
SESSION = scoped_session(sessionmaker(bind=ENGINE))


@contextmanager
def session_scope():
    """Provide a transactional scope around a series of db operations."""
    _session = SESSION()
    try:
        yield _session
        _session.commit()
    except:
        _session.rollback()
        raise
    finally:
        _session.close()