feat: inventory SMTP infrastructure dependencies

src/govoplan_mail/backend/configuration_provider.py

@@ -5,7 +5,7 @@ from dataclasses import dataclass, replace
 import re
 from typing import Any
 
-from sqlalchemy import or_, select
+from sqlalchemy import func, or_, select
 from sqlalchemy.orm import Session
 
 from govoplan_core.core.configuration_packages import (
@@ -24,6 +24,8 @@ from govoplan_core.core.configuration_packages import (
 from govoplan_core.core.infrastructure_capabilities import (
     InfrastructureCapability,
     InfrastructureCapabilityReceipt,
+    InfrastructureDependency,
+    InfrastructureDependencyProvider,
 )
 from govoplan_core.security.credential_envelopes import (
     CredentialAccessContext,
@@ -51,6 +53,9 @@ from govoplan_mail.backend.server_hierarchy import (
 
 
 MAIL_CONFIGURATION_CAPABILITY = "mail.configuration"
+MAIL_INFRASTRUCTURE_DEPENDENCY_CAPABILITY = (
+    "infrastructure.dependency_inventory.mail"
+)
 SMTP_PROFILE_FRAGMENT = "smtp_profile"
 _SYSTEM_CONFIGURATION_SCOPES = frozenset(
     {"system:settings:write", "system:governance:write"}
@@ -132,8 +137,12 @@ class _ProfileTarget:
     on_conflict: str
 
 
-class SqlMailConfigurationProvider(ConfigurationProvider):
+class SqlMailConfigurationProvider(
+    ConfigurationProvider,
+    InfrastructureDependencyProvider,
+):
     module_id = "mail"
+    capability_ids = ("mail.smtp",)
 
     def describe(self) -> ConfigurationProviderDescription:
         return ConfigurationProviderDescription(
@@ -204,6 +213,84 @@ class SqlMailConfigurationProvider(ConfigurationProvider):
             item for item in import_result.diagnostics if item.severity == "blocker"
         )
 
+    def infrastructure_dependencies(self) -> tuple[InfrastructureDependency, ...]:
+        with get_database().session() as session:
+            return _smtp_infrastructure_dependencies(session)
+
+
+def _smtp_infrastructure_dependencies(
+    session: Session,
+) -> tuple[InfrastructureDependency, ...]:
+    endpoints = tuple(
+        session.execute(
+            select(MailServerEndpoint)
+            .where(MailServerEndpoint.protocol == "smtp")
+            .order_by(MailServerEndpoint.id)
+        ).scalars()
+    )
+    binding_counts = {
+        str(server_id): int(count)
+        for server_id, count in session.execute(
+            select(
+                MailServerCredentialBinding.server_id,
+                func.count(MailServerCredentialBinding.id),
+            ).group_by(MailServerCredentialBinding.server_id)
+        )
+    }
+    dependencies: list[InfrastructureDependency] = []
+    endpoint_profile_ids: set[str] = set()
+    for endpoint in endpoints:
+        endpoint_profile_ids.add(endpoint.profile_id)
+        dependencies.append(
+            InfrastructureDependency(
+                capability_id="mail.smtp",
+                module_id="mail",
+                dependency_type="smtp_endpoint",
+                dependency_ref=mail_server_ref(endpoint.id) or f"mail:{endpoint.id}",
+                state="active" if endpoint.is_active else "inactive",
+                scope=str(endpoint.scope_type or "tenant"),
+                summary=(
+                    "A persisted Mail SMTP endpoint is bound to the deployment relay."
+                ),
+                metrics={
+                    "credential_binding_count": binding_counts.get(endpoint.id, 0),
+                    "default_endpoint": int(bool(endpoint.is_default)),
+                },
+                required_action=(
+                    "Rebind, migrate, or explicitly retire this SMTP endpoint and its credential-envelope references before changing the relay capability."
+                ),
+            )
+        )
+
+    legacy_profiles = tuple(
+        session.execute(
+            select(MailServerProfile)
+            .where(MailServerProfile.smtp_config.is_not(None))
+            .order_by(MailServerProfile.id)
+        ).scalars()
+    )
+    for profile in legacy_profiles:
+        if profile.id in endpoint_profile_ids or not dict(profile.smtp_config or {}):
+            continue
+        dependencies.append(
+            InfrastructureDependency(
+                capability_id="mail.smtp",
+                module_id="mail",
+                dependency_type="legacy_smtp_profile",
+                dependency_ref=f"mail-profile:{profile.id}",
+                state="active" if profile.is_active else "inactive",
+                scope=str(profile.scope_type or "tenant"),
+                summary=(
+                    "A persisted legacy Mail profile still contains SMTP transport configuration."
+                ),
+                metrics={"credential_binding_count": 0},
+                required_action=(
+                    "Migrate or explicitly retire this legacy profile before changing the relay capability."
+                ),
+            )
+        )
+    return tuple(dependencies)
+
 
 def _preflight_smtp_profile(
     session: Session,