Definition
Connects an application to a dependency that already exists instead of creating and managing a new instance.
- Also known as
- existing resource, AddConnectionString
For a dependency exposed through a connection string, use AddConnectionString in C# or addConnectionString in TypeScript to represent the configured value in the AppHost.
For a resource named db, Aspire reads ConnectionStrings:db from AppHost configuration, including the environment variable ConnectionStrings__db, and passes the value to referencing consumers.
This is useful for shared team resources or existing production services. The connection string resource does not create, migrate, or manage the database itself. Keep credentials in an appropriate secret store rather than source control.
Practical example
Supply a shared database's connection string in AppHost configuration and reference it from an API without starting another database container.
Aspire