Add serviceapps Django app for Cytoscape Web Service Apps

[kushvinth]

PR: Add Cytoscape Web Service Apps Support

Related Issues:

• Add Support for Cytoscape Web Service Apps to App Store #115

Summary

This PR adds a new serviceapps Django app that brings Cytoscape Web Service App support to the App Store. Service Apps, per the Service App Specification (draft v2), become a first-class app type, discoverable via the App Store UI and consumable via a machine-readable JSON API endpoint for Cytoscape Web.

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What's Included

URL Routes

URL	Name	Description
/submit/service-app/	serviceapps:submit	Form to submit & validate a new service app
/service-apps/	serviceapps:list	Browse active service apps (filter by ?health=ok or ?q=search)
/service-apps/<id>/	serviceapps:detail	Service app detail page
/api/service-apps/config	serviceapps:config	JSON endpoint returning [{"url": "..."}] for healthy apps, consumed by Cytoscape Web

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Submission & Validation Flow

When an author submits a service app URL:

1. The view fetches the root endpoint (/) and checks for required keys per the spec:
   name, description, version, parameters, serviceInputDefinition, cyWebActions, cyWebMenuItem
2. The view fetches /status and records the health state
3. If both checks pass, the ServiceApp record is created/updated with the fetched metadata
4. If any check fails, the form re-renders with a specific error message

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Health Check Command

python manage.py check_service_apps

Iterates over all active ServiceApp records, pings their /status endpoint, and updates last_status (ok, unavailable, or error), last_message, and last_checked. Designed to be run via cron or CI on a schedule.

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Django Dual-Import Fix

The Problem

This project has an unusual sys.path setup:

• manage.py appends .. to sys.path
• The project root directory contains an __init__.py (making it an appstore Python package)

This means every top-level app is importable via two paths:

• serviceapps (direct)
• appstore.serviceapps (via the root package)

When Django's test runner discovers tests, it imports modules via the appstore.serviceapps path. But Django's app registry already loaded the app as serviceapps. This causes the ServiceApp model class to be instantiated twice from two different module identities, leading to:

RuntimeError: Conflicting 'serviceapp' models in application 'serviceapps':
<class 'serviceapps.models.ServiceApp'> and <class 'appstore.serviceapps.models.ServiceApp'>

The existing apps (apps, download, submit_app, etc.) happen to avoid this because they don't have apps.py AppConfig files and Django's legacy app loading resolves them differently.

The Fix

In serviceapps/__init__.py, module canonicalization logic detects when the module is being imported via the alternate appstore.serviceapps path and maps it back to the canonical serviceapps entry in sys.modules. This ensures both import paths resolve to the same module objects, preventing Django from registering duplicate model classes.

_CANONICAL = 'serviceapps'
if __name__ != _CANONICAL and _CANONICAL in sys.modules:
    sys.modules[__name__] = sys.modules[_CANONICAL]
    # ... also maps submodules

This is a targeted fix scoped to serviceapps. A broader fix would be to remove the sys.path.append('..') from manage.py or remove the root __init__.py, but that would affect the entire project and is out of scope for this PR.

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Testing

# Run all serviceapps tests
python manage.py test serviceapps

# Run only non-template tests (avoids Django 4.2 + Python 3.14 __copy__ bug)
python manage.py test serviceapps.tests.ServiceAppModelTests \
                      serviceapps.tests.ServiceAppConfigTests \
                      serviceapps.tests.SubmitServiceAppTests.test_submit_valid_service

Test results: 11 tests total, 5 pass, 6 fail due to a pre-existing Django 4.2 + Python 3.14 incompatibility in template context copying (AttributeError: 'super' object has no attribute 'dicts'). This affects any view that renders a template, including tests in the existing apps test suite. It is not caused by this PR.

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Post-Merge Steps

1. Run migrations: python manage.py migrate
2. (Optional) Schedule the health check: python manage.py check_service_apps via cron
3. Consider upgrading Django to fix the Python 3.14 template __copy__ bug

[kushvinth]

PTAL @coleslaw481