A simple, type-friendly Python ORM.

Things one might expect of any ORM:

• Lightweight class-based models and descriptor-based fields
• Built-in fields for common types
• Primary keys
• Foreign keys with attribute accessors and joined queries
• Separate nullable fields

Things one might not:

• Reliable type signatures on the public API
• Support for any DB-API 2.0 database driver
• Synchronous and asynchronous operation under a common API

Low-level interaction with databases is handled by a DB-API Connection. This means you can work with any type of database, as long as a database driver exists that implements a DB-API interface -- Python's built-in SQLite library does so, whilst external modules are available for MySQL, PostgreSQL and others.

Whilst there's no asynchronous DB-API specification, some database drivers implement a DB-API-like interface with the same methods presented as coroutines; these are supported with asynchronous sessions, which will attempt to await results of Connection method calls if they return awaitables.

The included tests can be ran using:

$ make test

By default, this will just run generic tests, and SQLite tests against an in-memory database.

To run against MySQL or PostgreSQL, you'll need to install the database drivers used by the tests:

$ pip install -r requirements-dev.txt

Credentials must also be provided to connect to live database servers. These should be JSON-formatted strings containing kwargs for the underlying driver connection methods. For example, to connect to servers listening locally without authentication:

$ export TYDB_MYSQL_CONN='{"db": "tydb"}'
$ export TYDB_PGSQL_CONN='{"dbname": "tydb"}'

Only synchronous session and driver tests are run by default. To enable asynchronous tests too:

$ export TYDB_ASYNC=1

The dialect-aware tests currently use the following databases and drivers:

• MySQL
  • pymysql
  • aiomysql
• PostgreSQL
  • psycopg
  • aiopg
• SQLite
  • sqlite3 (built-in)
  • aiosqlite

These can be built using pdoc, assuming you've installed the dev requirements already:

$ make docs