Outername

Outername is a term used in information technology to describe the externally visible identifier assigned to a resource, as distinct from its internal technical identifiers, such as primary keys or system IDs. It is commonly employed in API design, configuration systems, and user-facing URLs to provide stable and human-readable references.

In practice, the outername is often a slug or label that remains stable even if internal identifiers change. It may be URL-safe, localized, or constrained by namespace rules.

In RESTful APIs, the outername may appear in the resource path, e.g., /users/john-doe, where john-doe is the outername, while the system stores an internal ID.

Advantages include decoupling external identity from internal storage, improving readability and usability. Risks include renaming issues, collisions, and the need for mapping layers. Best practices: enforce immutability, validate uniqueness, maintain a redirection or aliasing mechanism when renamed.

Alternatives include slug, public name, and external identifier.

See also: slug, public identifier, namespace.