feat: compose stable product surfaces

src/govoplan_core/core/modules.py

@@ -30,6 +30,7 @@ if TYPE_CHECKING:
 SUPPORTED_MANIFEST_CONTRACT_VERSION = "1"
 SUPPORTED_FRONTEND_ASSET_MANIFEST_CONTRACT_VERSION = "1"
 SUPPORTED_PRESENTATION_CONTRACT_VERSION = "1"
+SUPPORTED_PRODUCT_SURFACE_CONTRACT_VERSION = "1"
 
 PermissionLevel = Literal["system", "tenant"]
 SubjectType = Literal["account", "membership", "group", "service_account", "tenant"]
@@ -114,6 +115,55 @@ class ProductAreaContribution:
     order: int = 100
 
 
+ProductSurfacePresentation = Literal["task", "reader", "admin", "operator"]
+ProductAvailabilityReason = Literal[
+    "authorization",
+    "policy",
+    "configuration",
+    "disabled",
+    "capability",
+    "offline",
+    "provider_degraded",
+]
+
+
+@dataclass(frozen=True, slots=True)
+class ProductAvailabilityExplanation:
+    """Explain a product outcome without making package topology user-facing."""
+
+    reason: ProductAvailabilityReason
+    title: str
+    description: str
+    resolution: str
+    responsible_role: str | None = None
+
+
+@dataclass(frozen=True, slots=True)
+class ProductSurfaceContribution:
+    """Bind an owner route to a stable, cross-module product identity."""
+
+    id: str
+    module_id: str
+    label: str
+    icon: str
+    entry_path: str
+    route_path: str
+    surface_ids: tuple[str, ...]
+    unavailable: ProductAvailabilityExplanation
+    description: str | None = None
+    degraded: ProductAvailabilityExplanation | None = None
+    presentations: tuple[ProductSurfacePresentation, ...] = ("task",)
+    capability_ids: tuple[str, ...] = ()
+    search_source_ids: tuple[str, ...] = ()
+    help_context_ids: tuple[str, ...] = ()
+    documentation_topic_ids: tuple[str, ...] = ()
+    required_all: tuple[str, ...] = ()
+    required_any: tuple[str, ...] = ()
+    aliases: tuple[str, ...] = ()
+    order: int = 100
+    contract_version: str = SUPPORTED_PRODUCT_SURFACE_CONTRACT_VERSION
+
+
 @dataclass(frozen=True, slots=True)
 class QuickAccessTool:
     """Declare a versioned, bounded module-owned Quick Access tool."""
@@ -153,6 +203,7 @@ class FrontendModule:
     settings_routes: tuple[FrontendRoute, ...] = ()
     view_surfaces: tuple[ViewSurface, ...] = ()
     product_areas: tuple[ProductAreaContribution, ...] = ()
+    product_surfaces: tuple[ProductSurfaceContribution, ...] = ()
     quick_access_tools: tuple[QuickAccessTool, ...] = ()
 
 

src/govoplan_core/core/platform_interfaces.py

@@ -22,6 +22,7 @@ PlatformInterfaceKind = Literal[
     "navigation",
     "permission",
     "product_area",
+    "product_surface",
     "provided_interface",
     "public_route",
     "search_provider",
@@ -237,6 +238,41 @@ def manifest_interface_declarations(
                     },
                 )
             )
+        for surface in frontend.product_surfaces:
+            declarations.append(
+                PlatformInterfaceDeclaration(
+                    id=f"{manifest.id}.{surface.id}",
+                    module_id=manifest.id,
+                    kind="product_surface",
+                    label=surface.label,
+                    path=surface.route_path,
+                    required_all=surface.required_all,
+                    required_any=surface.required_any,
+                    metadata={
+                        "contract_version": surface.contract_version,
+                        "product_surface_id": surface.id,
+                        "description": surface.description,
+                        "icon": surface.icon,
+                        "entry_path": surface.entry_path,
+                        "surface_ids": list(surface.surface_ids),
+                        "presentations": list(surface.presentations),
+                        "capability_ids": list(surface.capability_ids),
+                        "search_source_ids": list(surface.search_source_ids),
+                        "help_context_ids": list(surface.help_context_ids),
+                        "documentation_topic_ids": list(
+                            surface.documentation_topic_ids
+                        ),
+                        "aliases": list(surface.aliases),
+                        "order": surface.order,
+                        "unavailable_reason": surface.unavailable.reason,
+                        "degraded_reason": (
+                            surface.degraded.reason
+                            if surface.degraded is not None
+                            else None
+                        ),
+                    },
+                )
+            )
         for tool in frontend.quick_access_tools:
             declarations.append(
                 PlatformInterfaceDeclaration(

src/govoplan_core/core/registry.py

@@ -16,13 +16,16 @@ from govoplan_core.core.modules import (
     ModuleManifest,
     NavItem,
     PermissionDefinition,
+    ProductAvailabilityExplanation,
     ProductAreaContribution,
+    ProductSurfaceContribution,
     PublicFrontendRoute,
     QuickAccessTool,
     ResourceAclProvider,
     RoleTemplate,
     SUPPORTED_FRONTEND_ASSET_MANIFEST_CONTRACT_VERSION,
     SUPPORTED_MANIFEST_CONTRACT_VERSION,
+    SUPPORTED_PRODUCT_SURFACE_CONTRACT_VERSION,
     TenantSummaryBatchProvider,
     TenantSummaryProvider,
     user_workflow_scope_condition_issues,
@@ -90,6 +93,9 @@ _WILDCARD_RE = re.compile(
 )
 _INTERFACE_NAME_RE = re.compile(r"^[a-z][a-z0-9_]*(?:\.[a-z][a-z0-9_]*)+$")
 _PRESENTATION_ID_RE = re.compile(r"^[a-z][a-z0-9_-]{1,79}$")
+_PRODUCT_SURFACE_ID_RE = re.compile(
+    r"^[a-z][a-z0-9_-]*(?:\.[a-z][a-z0-9_-]*)+$"
+)
 _QUICK_ACCESS_TOOL_ID_RE = re.compile(
     r"^[a-z][a-z0-9_]*(?:\.[a-z][a-z0-9_-]*)+$"
 )
@@ -974,7 +980,19 @@ def _validate_manifest_shape(manifest: ModuleManifest) -> None:
 
 def _validate_presentation_catalog(manifests: tuple[ModuleManifest, ...]) -> None:
     area_definitions: dict[str, tuple[str, str]] = {}
+    surface_definitions: dict[str, tuple[str, str, str, str | None]] = {}
+    product_paths: dict[str, str] = {}
     tool_owners: dict[str, str] = {}
+    concrete_paths = {
+        route.path: manifest.id
+        for manifest in manifests
+        if manifest.frontend is not None
+        for route in (
+            *manifest.frontend.routes,
+            *manifest.frontend.settings_routes,
+            *manifest.frontend.public_routes,
+        )
+    }
     for manifest in manifests:
         frontend = manifest.frontend
         if frontend is None:
@@ -987,6 +1005,33 @@ def _validate_presentation_catalog(manifests: tuple[ModuleManifest, ...]) -> Non
                     f"Product area {area.id!r} has conflicting labels or icons"
                 )
             area_definitions[area.id] = definition
+        for surface in frontend.product_surfaces:
+            definition = (
+                surface.label,
+                surface.icon,
+                surface.entry_path,
+                surface.description,
+            )
+            previous = surface_definitions.get(surface.id)
+            if previous is not None and previous != definition:
+                raise RegistryError(
+                    f"Product surface {surface.id!r} has conflicting product identity metadata"
+                )
+            surface_definitions[surface.id] = definition
+            for path in (surface.entry_path, *surface.aliases):
+                concrete_owner = concrete_paths.get(path)
+                if concrete_owner is not None:
+                    raise RegistryError(
+                        f"Product path {path!r} collides with a concrete route "
+                        f"owned by module {concrete_owner!r}"
+                    )
+                previous_id = product_paths.get(path)
+                if previous_id is not None and previous_id != surface.id:
+                    raise RegistryError(
+                        f"Product path {path!r} is shared by product surfaces "
+                        f"{previous_id!r} and {surface.id!r}"
+                    )
+                product_paths[path] = surface.id
         for tool in frontend.quick_access_tools:
             previous_owner = tool_owners.get(tool.id)
             if previous_owner is not None:
@@ -1474,6 +1519,14 @@ def _validate_presentation_contributions(manifest: ModuleManifest) -> None:
                     f"in module {manifest.id!r}"
                 )
             seen_area_memberships.add(membership)
+    seen_product_surfaces: set[str] = set()
+    for surface in frontend.product_surfaces:
+        _validate_product_surface(manifest, surface, known_surface_ids)
+        if surface.id in seen_product_surfaces:
+            raise RegistryError(
+                f"Duplicate product surface {surface.id!r} in module {manifest.id!r}"
+            )
+        seen_product_surfaces.add(surface.id)
     seen_tools: set[str] = set()
     for tool in frontend.quick_access_tools:
         _validate_quick_access_tool(manifest.id, tool, known_surface_ids)
@@ -1512,6 +1565,151 @@ def _validate_product_area(
         )
 
 
+def _validate_product_surface(
+    manifest: ModuleManifest,
+    surface: ProductSurfaceContribution,
+    known_surface_ids: set[str],
+) -> None:
+    module_id = manifest.id
+    frontend = manifest.frontend
+    assert frontend is not None
+    if surface.module_id != module_id:
+        raise RegistryError(
+            f"Product surface {surface.id!r} belongs to {surface.module_id!r}, "
+            f"not module {module_id!r}"
+        )
+    if not _PRODUCT_SURFACE_ID_RE.fullmatch(surface.id):
+        raise RegistryError(f"Invalid product surface id: {surface.id!r}")
+    if surface.contract_version != SUPPORTED_PRODUCT_SURFACE_CONTRACT_VERSION:
+        raise RegistryError(
+            f"Product surface {surface.id!r} uses unsupported contract version "
+            f"{surface.contract_version!r}"
+        )
+    if not surface.label.strip() or not surface.icon.strip():
+        raise RegistryError(
+            f"Product surface {surface.id!r} needs a label and icon"
+        )
+    for label, path in (
+        ("entry", surface.entry_path),
+        ("owner", surface.route_path),
+        *(("alias", alias) for alias in surface.aliases),
+    ):
+        if not path.startswith("/") or "?" in path or "#" in path:
+            raise RegistryError(
+                f"Product surface {surface.id!r} has an invalid {label} path {path!r}"
+            )
+    if (
+        surface.entry_path == surface.route_path
+        or surface.entry_path in surface.aliases
+        or surface.route_path in surface.aliases
+    ):
+        raise RegistryError(
+            f"Product surface {surface.id!r} must keep its stable entry distinct from owner and alias paths"
+        )
+    if len(set(surface.aliases)) != len(surface.aliases):
+        raise RegistryError(
+            f"Product surface {surface.id!r} contains duplicate aliases"
+        )
+    route_paths = {route.path for route in (*frontend.routes, *frontend.settings_routes)}
+    if surface.route_path not in route_paths:
+        raise RegistryError(
+            f"Product surface {surface.id!r} references unknown owner route "
+            f"{surface.route_path!r}"
+        )
+    if not surface.surface_ids:
+        raise RegistryError(
+            f"Product surface {surface.id!r} has no owner surfaces"
+        )
+    unknown_surfaces = set(surface.surface_ids) - known_surface_ids
+    if unknown_surfaces:
+        raise RegistryError(
+            f"Product surface {surface.id!r} references unknown surfaces: "
+            + ", ".join(sorted(unknown_surfaces))
+        )
+    allowed_presentations = {"task", "reader", "admin", "operator"}
+    if (
+        not surface.presentations
+        or len(set(surface.presentations)) != len(surface.presentations)
+        or set(surface.presentations) - allowed_presentations
+    ):
+        raise RegistryError(
+            f"Product surface {surface.id!r} has invalid presentations"
+        )
+    declared_capabilities = {
+        *manifest.required_capabilities,
+        *manifest.optional_capabilities,
+        *manifest.capability_factories,
+        *(provider.name for provider in manifest.provides_interfaces),
+        *(requirement.name for requirement in manifest.requires_interfaces),
+    }
+    unknown_capabilities = set(surface.capability_ids) - declared_capabilities
+    if unknown_capabilities:
+        raise RegistryError(
+            f"Product surface {surface.id!r} references undeclared capabilities: "
+            + ", ".join(sorted(unknown_capabilities))
+        )
+    search_source_ids = {source.id for source in manifest.search_sources}
+    unknown_search_sources = set(surface.search_source_ids) - search_source_ids
+    if unknown_search_sources:
+        raise RegistryError(
+            f"Product surface {surface.id!r} references unknown search sources: "
+            + ", ".join(sorted(unknown_search_sources))
+        )
+    topics = {topic.id: topic for topic in manifest.documentation}
+    unknown_topics = set(surface.documentation_topic_ids) - set(topics)
+    if unknown_topics:
+        raise RegistryError(
+            f"Product surface {surface.id!r} references unknown documentation topics: "
+            + ", ".join(sorted(unknown_topics))
+        )
+    documented_help_contexts: set[str] = set()
+    for topic in manifest.documentation:
+        contexts = topic.metadata.get("help_contexts", ())
+        if isinstance(contexts, (list, tuple, set, frozenset)):
+            documented_help_contexts.update(
+                context for context in contexts if isinstance(context, str)
+            )
+    unknown_help = set(surface.help_context_ids) - documented_help_contexts
+    if unknown_help:
+        raise RegistryError(
+            f"Product surface {surface.id!r} references undocumented help contexts: "
+            + ", ".join(sorted(unknown_help))
+        )
+    _validate_product_availability_explanation(surface.id, surface.unavailable)
+    if surface.degraded is not None:
+        _validate_product_availability_explanation(surface.id, surface.degraded)
+
+
+def _validate_product_availability_explanation(
+    surface_id: str,
+    explanation: ProductAvailabilityExplanation,
+) -> None:
+    allowed_reasons = {
+        "authorization",
+        "policy",
+        "configuration",
+        "disabled",
+        "capability",
+        "offline",
+        "provider_degraded",
+    }
+    if explanation.reason not in allowed_reasons:
+        raise RegistryError(
+            f"Product surface {surface_id!r} has an invalid availability reason"
+        )
+    if any(
+        not value.strip()
+        for value in (
+            explanation.title,
+            explanation.description,
+            explanation.resolution,
+        )
+    ):
+        raise RegistryError(
+            f"Product surface {surface_id!r} has an incomplete availability explanation"
+        )
+
+
 def _validate_quick_access_tool(
     module_id: str,
     tool: QuickAccessTool,

src/govoplan_core/server/platform.py

@@ -22,7 +22,9 @@ from govoplan_core.core.modules import (
     FrontendRoute,
     ModuleManifest,
     NavItem,
+    ProductAvailabilityExplanation,
     ProductAreaContribution,
+    ProductSurfaceContribution,
     PublicFrontendRoute,
     QuickAccessTool,
     SUPPORTED_PRESENTATION_CONTRACT_VERSION,
@@ -254,6 +256,47 @@ def _product_area_payload(area: ProductAreaContribution) -> dict[str, object]:
     }
 
 
+def _product_availability_payload(
+    explanation: ProductAvailabilityExplanation,
+) -> dict[str, object]:
+    return {
+        "reason": explanation.reason,
+        "title": explanation.title,
+        "description": explanation.description,
+        "resolution": explanation.resolution,
+        "responsible_role": explanation.responsible_role,
+    }
+
+
+def _product_surface_payload(surface: ProductSurfaceContribution) -> dict[str, object]:
+    return {
+        "contract_version": surface.contract_version,
+        "id": surface.id,
+        "module_id": surface.module_id,
+        "label": surface.label,
+        "description": surface.description,
+        "icon": surface.icon,
+        "entry_path": surface.entry_path,
+        "route_path": surface.route_path,
+        "surface_ids": list(surface.surface_ids),
+        "presentations": list(surface.presentations),
+        "capability_ids": list(surface.capability_ids),
+        "search_source_ids": list(surface.search_source_ids),
+        "help_context_ids": list(surface.help_context_ids),
+        "documentation_topic_ids": list(surface.documentation_topic_ids),
+        "required_all": list(surface.required_all),
+        "required_any": list(surface.required_any),
+        "aliases": list(surface.aliases),
+        "order": surface.order,
+        "unavailable": _product_availability_payload(surface.unavailable),
+        "degraded": (
+            _product_availability_payload(surface.degraded)
+            if surface.degraded is not None
+            else None
+        ),
+    }
+
+
 def _quick_access_tool_payload(tool: QuickAccessTool) -> dict[str, object]:
     return {
         "id": tool.id,
@@ -372,6 +415,10 @@ def _frontend_payload(
         "product_areas": [
             _product_area_payload(area) for area in frontend.product_areas
         ],
+        "product_surfaces": [
+            _product_surface_payload(surface)
+            for surface in frontend.product_surfaces
+        ],
         "quick_access_tools": [
             _quick_access_tool_payload(tool) for tool in frontend.quick_access_tools
         ],