amacfie / sqlafunccodegen

sqlacodegen for postgres functions

sqlafunccodegen

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

Benefit over PostgREST: You can call functions and execute other SQL within a transaction.

Usage:

sqlafunccodegen --help

Capabilities:

• "func" mode: functions directly wrap sqlalchemy.func.<function_name>
  • no types, just parameter names
• "python" and "asyncpg_only" modes: functions execute a select statement and return results
  • many basic types
  • enums
  • arrays
  • Pydantic models for user-defined composite types
  • set-returning functions return iterables
  • constraints in domains are not checked but the underlying type is used
  • the Python types may be too restrictive or not restrictive enough, the correspondence isn't perfect. some types aren't recognized and the generic form in which sqlafunccodegen attempts to send them to the database may not work.
• all modes:
  • comments as docstrings
  • functions with overloads not supported
  • polymorphic pseudo-types not supported
  • IN, INOUT, and VARIADIC params not supported
  • default values are not available

Generated code dependencies:

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

Examples

• input: tests/schema.ddl
• "python" mode output: tests/out_python.py
• "func" mode output: tests/out_func.py
• "asyncpg_only" mode output: tests/out_asyncpg_only.py