husrev

Creates each SQLAlchemy class file separately


Keywords
fastapi, flask, mysql, postgresql, sql, sqlachemy
License
Other
Install
pip install husrev==1.5.3

Documentation

This tool has been forked from at GitHub Python 3 and the latest SQLAlchemy version).

This is a tool that reads the structure of an existing database and generates
the appropriate SQLAlchemy model classes, using the declarative style if
possible.

Features

  • Supports SQLAlchemy
  • Produces declarative code that almost looks like it was hand written
  • Produces PEP 8 compliant code
  • Accurately determines relationships, including many-to-many, one-to-one
  • Automatically detects joined table inheritance
  • Excellent test coverage
  • It creates each SQLAlchemy class file separately under the "models" folder.

Usage instructions

Installation

To install, do:

pip install husrev

or, failing that:

easy_install husrev

Example usage

At the minimum, you have to give husrev a database URL.
The URL is passed directly to SQLAlchemy's
create_engine() method so please refer to SQLAlchemy's documentation http://docs.sqlalchemy.org/en/latest/core/engines.html for instructions on how to construct a proper URL.

Examples:

husrev postgresql:///some_local_db --noinflect

husrev mysql+oursql://user:password@localhost/dbname

husrev sqlite:///database.db

To see the full list of options:

husrev --help

Model class naming logic

The table name (which is assumed to be in English) is converted to singular
form using the "inflect" library. Then, every underscore is removed while
transforming the next letter to upper case. For example, sales_invoices
becomes SalesInvoice.

Use --noinflect disable inflect transform.

Relationship detection logic

Relationships are detected based on existing foreign key constraints as
follows:

  • many-to-one: a foreign key constraint exists on the table
  • one-to-one: same as many-to-one, but a unique constraint exists on
    the column(s) involved
  • many-to-many: an association table is found to exist between two tables

A table is considered an association table if it satisfies all of the
following conditions:

#. has exactly two foreign key constraints
#. all its columns are involved in said constraints

Relationship naming logic

Relationships are typically named based on the opposite class name.
For example, if an Employee class has a column named employer which
has a foreign key to Company.id, the relationship is named company.

A special case for single column many-to-one and one-to-one relationships,
however, is if the column is named like employer_id. Then the
relationship is named employer due to that _id suffix.

If more than one relationship would be created with the same name, the
latter ones are appended numeric suffixes, starting from 1.

Source code

The source can be browsed at GitHub

Reporting bugs

A bug tracker is provided by GitHub.