AddLiteBus (Microsoft DI)

Header

• ID: hosting.add-lite-bus-microsoft-di
• Name: AddLiteBus (Microsoft DI)
• Maturity: GA
• Summary: Composes LiteBus modules through IServiceCollection and publishes a host manifest for hosting bridges.

What It Does

IServiceCollection.AddLiteBus(...) is the Microsoft DI entry point for LiteBus composition. Its Action<ILiteBusBuilder> callback builds module order, executes module Build(...), registers LiteBusHostManifest, and wires diagnostic checks and background hosting registrations. Advanced callers register custom modules through builder.Modules inside the same callback.

This capability is composition only. It does not own ASP.NET routes, health checks, or exporters.

Public Surface

Invocation

• IServiceCollection AddLiteBus(Action<ILiteBusBuilder> configure)

Registration

• Registers LiteBusHostManifest as singleton.
• Applies RegisterDiagnosticChecks(...) from LiteBus.Runtime.Extensions.Microsoft.Hosting.
• Applies RegisterBackgroundServices(...) from LiteBus.Runtime.Extensions.Microsoft.Hosting.
• Registers one Microsoft DI-backed IMessageDispatchScopeFactory for mediation and durable processor scopes.

Configuration

• Action<ILiteBusBuilder> for package-owned Add* feature extensions and advanced builder.Modules access.

Packages

• LiteBus.Runtime.Extensions.Microsoft.DependencyInjection
• LiteBus.Runtime.Extensions.Microsoft.Hosting (transitive hosting bridge registration)

Requires

• hosting.module-registry
• hosting.host-manifest
• hosting.microsoft-hosting-bridge

Invariants

• Module build order is frozen after BuildOrder().
• LiteBusHostManifest reflects startup tasks, background services, and diagnostic checks collected during composition.
• Each dispatch opens and disposes an IServiceScope.

Non-Goals

• Not an Autofac adapter.
• Not a runtime endpoint or management API.
• Does not register OpenTelemetry exporters.

Observability

No direct telemetry is emitted by AddLiteBus. Operational visibility comes from downstream capabilities:

• hosting.host-manifest for resolved manifest contents
• hosting.aspnet-health-checks and hosting.aspnet-management-endpoints for probe output
• hosting.opentelemetry-* for meter and trace registration

Test Coverage

Covered Use Cases

LiteBusBuilderTests.AddLiteBus_WithMessagingContracts_ShouldRegisterContractsInResolvedRegistry

• Use case: messaging contract registrations become available in the resolved contract registry
• Test kind: Unit
• Description: configures services.AddLiteBus(builder => ...) with contracts through AddMessaging
• Behavior: resolves IMessageContractRegistry and looks up configured contract
• Expected outcome: contract name and version map to expected message type
• Remarks: tests/LiteBus.Runtime.UnitTests/LiteBusBuilderTests.cs

LiteBusBuilderTests.AddLiteBus_WithMultipleMessagingContracts_ShouldApplyAllRegistrations

• Use case: multiple messaging contracts coexist in one composition
• Test kind: Unit
• Description: registers two contracts in a single messaging builder callback
• Behavior: resolves registry and queries both contracts
• Expected outcome: both lookups succeed with expected types
• Remarks: tests/LiteBus.Runtime.UnitTests/LiteBusBuilderTests.cs

ModuleConfigurationDiagnosticCheckTests.AddLiteBus_ShouldRegisterLiteBusHostManifestWithDiagnosticChecks

• Use case: manifest captures diagnostic checks from module builders
• Test kind: Unit
• Description: composes message plus inbox modules and registers a diagnostic check
• Behavior: resolves LiteBusHostManifest
• Expected outcome: manifest contains expected check type and name
• Remarks: tests/LiteBus.Runtime.UnitTests/ModuleConfigurationDiagnosticCheckTests.cs

Untested Use Cases

Out-of-Scope Use Cases

• Runtime endpoint authorization and route policies.
• Exporter and sink configuration for observability backends.

Deep Docs

• Hosted services
• Diagnostics and health