baltimore-patapsco 0.4.0

Shared Django runtime foundations for Baltimore civic applications

baltimore-patapsco (Python)

Reusable Django runtime primitives for Baltimore civic applications.

INSTALLED_APPS += ["baltimore.patapsco"]

REST_FRAMEWORK = {
    "EXCEPTION_HANDLER": "baltimore.patapsco.api.exception_handler",
}

urlpatterns = [path("", include("baltimore.patapsco.urls"))]

Place RequestContextMiddleware early in MIDDLEWARE — after SecurityMiddleware (and WhiteNoise when present), before session, auth, and anything that can short-circuit a response — so every later middleware, view, and log line sees the bound request ID. The reference app shows the canonical order:

MIDDLEWARE = [
    "django.middleware.security.SecurityMiddleware",
    "whitenoise.middleware.WhiteNoiseMiddleware",
    "baltimore.patapsco.observability.RequestContextMiddleware",
    # sessions, common, csrf, auth, messages, clickjacking...
]

Stable health and readiness views

Applications that mount or extend the operational views directly use the public facade:

from baltimore.patapsco.api import HealthView, ReadinessView

HealthView is process-only liveness. ReadinessView runs the established database check and returns its public-safe 200 or 503 status document. Both use no authentication classes and AllowAny, and both remain ordinary DRF APIView classes with as_view().

An application may subclass either class, override get(), and call super().get(request) before composing app-owned public-safe checks. The parent response status, request ID, and database result remain the starting contract; the application owns an explicit serializer and OpenAPI annotation for any extended payload.

The previous baltimore.patapsco.api.views imports resolve to the same class objects for compatibility. DiagnosticsView remains available only from that module and through the packaged URL configuration; it is intentionally absent from baltimore.patapsco.api.__all__ because its staff/public policy is a separate operational surface. The settings-free package root exports neither view class.

api_error_response() and the DRF exception handler force every 5xx response to the public internal_error code, generic message, and no details. Application callers cannot opt a server failure out of that safety boundary.

Use build_logging_config() for the shared JSON/pretty log shape. Modules are incrementally adoptable; installing the package does not enable auth, email, or Sentry by itself.

Sentry privacy defaults

Install the observability extra and call the shared initializer only when a DSN is configured:

from baltimore.patapsco.observability import configure_sentry

configure_sentry(
    environment="production",
    release="my-app@1.2.3",
    traces_sample_rate=0.1,
)

configure_sentry() is deny-by-default: it disables automatic PII, request-body capture, and stack-frame local variables. Its event pipeline also removes request cookies and query strings, strips query/fragment data from request URLs, and recursively redacts Sentry's credential/session denylist plus common civic contact and precise-location fields. Safe operational fields such as request IDs, routes, and HTTP methods remain available.

Redaction is key-based. Applications must not attach sensitive values under misleading keys or place resident data in exception messages. Product-specific fields still require a privacy review before being added to Sentry context.

Configuration surface

Everything the library reads from the environment or Django settings:

Name	Kind	Default	Meaning
APP_ENV	env var	local	Environment label in diagnostics and Sentry events; overridden by PATAPSCO_ENVIRONMENT when set
APP_RELEASE	env var	—	Release identifier in diagnostics and Sentry events; overridden by PATAPSCO_RELEASE when set
APP_LOG_FORMAT	env var	json	json or pretty output from build_logging_config()
APP_LOG_LEVEL	env var	INFO	Root log level from build_logging_config()
SENTRY_DSN	env var	—	Enables configure_sentry(); absent means Sentry stays off
PATAPSCO_SERVICE_NAME	Django setting	project name	Service label in the diagnostics payload
PATAPSCO_ENVIRONMENT	Django setting	APP_ENV env var	Overrides the diagnostics environment field via Django settings instead of the process environment (a real override_settings test seam)
PATAPSCO_RELEASE	Django setting	APP_RELEASE env var	Overrides the diagnostics release field via Django settings instead of the process environment (a real override_settings test seam)
PATAPSCO_DIAGNOSTICS_PUBLIC	Django setting	False	Security-relevant: flips /api/diagnostics from IsAdminUser to AllowAny. Leave False unless the deployment deliberately publishes runtime metadata