fix(admin): register moved hogflow and cdp admins via package init

[dmarchuk]

Problem

The recent move of the workflows and CDP models into their product apps (#60248) also relocated their Django admin classes into admin/ packages (products/cdp/backend/admin/ and products/workflows/backend/admin/), split across submodules — but the package __init__.py files were left empty.

PostHog registers admins lazily through autodiscover_modules("admin"), which imports only each app's top-level admin module — i.e. the package's __init__.py. With an empty __init__, the submodules holding the @admin.register decorators were never imported, so HogFlow, HogFunction, Plugin, and PluginConfig silently disappeared from Django admin. Every other product uses a single admin.py file, which autodiscover imports directly, so only these two packaged products were affected.

Changes

Fix the regression — import the decorator-bearing submodules from each package __init__.py so their @admin.register decorators fire during autodiscover. This restores exactly the four admins that existed before the move (HogFlow, HogFunction, Plugin, PluginConfig).

New admins (net-new, not part of the regression) — while verifying the workflows admin section, two workflows models had never had a Django admin at all. This PR adds them:

• HogFlowTemplate — workflow templates, grouped under Workflows.
• HogFlowBatchJob — batch/broadcast job runs, grouped under Workflows.

Both are read-oriented: foreign-key fields (team, created_by, and hog_flow for the batch job) are declared readonly so the admin change pages don't render full-table <select> widgets, and JSON payload fields are readonly. team/hog_flow render as links to their respective admin change pages.

Regression test — posthog/admin/test_admin.py::TestProductAdminRegistration asserts all six models are registered after register_all_admin().

How did you test this code?

I manually tested with locally checked out branch that all the models load as they should.

I'm an agent — I did not do manual UI testing. Automated verification only:

• Booted Django and checked admin.site.is_registered(...): before the fix the four moved models returned False; after, all True. Confirmed the two new models register and their admin change/changelist URLs reverse cleanly.
• The regression test fails without the __init__.py fix and passes with it.
• ruff check / ruff format clean; pre-commit hooks including ty check passed.

🤖 Agent context

Authored by Claude Code at the request of the PR author.

Root cause traced to #60248: that move turned two products' admin modules into packages whose __init__.py was empty, breaking the autodiscover_modules("admin") registration path. Chose explicit submodule imports over the central registry's dynamic pkgutil.iter_modules approach since there are only a few files and it's clearer/grep-friendly. After confirming nothing was missing relative to the pre-move baseline, the author asked to also add admins for the two previously-unregistered workflows models (HogFlowTemplate, HogFlowBatchJob) — these are additive. plugin_attachment_inline is intentionally not imported explicitly: it has no @admin.register decorator and is already pulled in transitively by plugin_config_admin.

Note for reviewers: HogFlowBatchJob has a post_save signal that enqueues a real job invocation on create. The admin allows creates by default (consistent with other admins); flag if you'd prefer add disabled there.

https://claude.ai/code/session_01JaMLKbh61S5uYBQvBgCM77

[greptile-apps]

Prompt To Fix All With AI

Fix the following 1 code review issue. Work through them one at a time, proposing concise fixes.

---

### Issue 1 of 1
posthog/admin/test_admin.py:178-182
The team prefers parameterised tests. A `for` loop over models in a single test method means a failure on the first unregistered model silences all subsequent ones. `@pytest.mark.parametrize` gives independent pass/fail signals per model and clearer CI output.

```suggestion
    @pytest.mark.parametrize(
        "model",
        [HogFlow, HogFlowTemplate, HogFlowBatchJob, HogFunction, Plugin, PluginConfig],
        ids=lambda m: m.__name__,
    )
    def test_moved_product_models_are_registered(self, model):
        # Tests skip the lazy admin registry, so trigger registration explicitly.
        register_all_admin()
        assert admin.site.is_registered(model), f"{model.__name__} is not registered in Django admin"
```

_{Reviews (1): Last reviewed commit: "feat(admin): add HogFlowTemplate and Hog..." | Re-trigger Greptile}

[deployment-status-posthog]

Deploy status

Environment	Status	Deployed At	Workflow
dev	✅ Deployed	2026-06-01 06:36 UTC	Run
prod-us	✅ Deployed	2026-06-01 06:49 UTC	Run
prod-eu	✅ Deployed	2026-06-01 06:49 UTC	Run