from hat import rabbit: Hacking your way through Python's import machinery for fun and profit
summary
Claim: make Django believe SQL-only migrations are real Python migration modules so Django can import and run them without duplicating files. Uses the import machinery: sys.meta_path, custom finder/loader and a sys.path_hooks path-entry hook, plus pkgutil.iter_modules and ModuleSpec mechanics. Builds virtual migration package and per-migration modules on the fly, registers them at runtime, and it works — used to let procrastinate expose PostgreSQL SQL migrations to Django with no disk files written.
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chapters (12)
- 0:00Start
- 0:16Joakim Jablon
- 3:03What a Sql Migration Is
- 6:49Procrastinate Sql Migrations
- 7:43Migrations
- 8:39Virtual Migration Files
- 9:55The Structure of the Import Machinery
- 10:30The Import Statement
- 15:33Sysdot Metapath
- 17:19Path Entries
- 25:09Create an Importer
- 27:55Item Modules
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