2 Managing infrastructure components with containers and integrations

This chapter introduces two main ways to connect infrastructure components to an Aspire application: by running them as Docker containers or by using Aspire integration libraries. It uses security infrastructure as the main example, but the ideas are meant to apply broadly to other enterprise services as well. Along the way, it explains why distributed applications often need shared services such as identity providers, caches, databases, and brokers, and how Aspire helps reduce duplicated configuration through service discovery and shared references.

The chapter first builds a clear picture of Docker containers, emphasizing that they package an application and its dependencies into lightweight, isolated, portable units. It then walks through adding a Keycloak container to an Aspire host, mounting realm data, setting environment variables, and wiring the container into both a web frontend and an API service. The authentication setup shows how the frontend uses OpenID Connect while the API uses JWT bearer authentication, with Aspire service discovery and backchannel HTTP clients used to resolve the identity provider cleanly in development.

The second half shifts to Aspire integrations, showing how they differ from raw containers by providing a higher-level way to host and consume services such as Redis. The Redis example demonstrates how the host registers the component and how the application consumes it for output caching. Finally, the chapter builds a custom Aspire integration from scratch using MailDev, illustrating the structure of an integration library, how it exposes resources and endpoints, and how it is launched from the Aspire host. The overall message is that Aspire makes infrastructure easier to compose, safer to configure, and more reusable across services.