sqlafunccodegen

Generate type-annotated Python functions that wrap PostgreSQL functions, using asyncpg and, optionally, SQLAlchemy. Like sqlacodegen but for functions instead of tables.

Usage:

sqlafunccodegen --help

• all modes:
  • many basic types
  • arrays
  • comments as docstrings
  • casts on inputs are added for convenience
• "sqlalchemy" mode: functions behave like sqlalchemy.func.<function_name>
  • functions can be used inside SQLAlchemy query expressions
  • note: if a function call cannot return null, you can wrap the call with sqlalchemy.NotNullable and None will be removed as a possible Python type for the expression
• "asyncpg_only" mode: functions execute a select statement and return results
  • Python Enum types
  • Pydantic models for user-defined composite types
  • set-returning functions return lists
  • constraints in domains are NOT checked but the underlying type is used
  • note: sqlafunccodegen assumes that JSON/JSONB types are encoded as Python JSON types as in https://magicstack.github.io/asyncpg/current/usage.html#example-automatic-json-conversion
• not supported:
  • functions with overloads
  • polymorphic pseudo-types
  • IN, INOUT, and VARIADIC params
  • default values

Generated code dependencies:

• asyncpg
• Pydantic 2 (for "asyncpg_only" mode)
• SQLAlchemy 2 (for "sqlalchemy" mode)

Examples

• input: tests/schema.ddl
• "sqlalchemy" mode output: tests/out_sqlalchemy.py
• "asyncpg_only" mode output: tests/out_asyncpg_only.py