Route parameter
A route parameter is a named variable embedded in a URL path whose value is captured from a matching request to identify or select a resource or operation.
The Design of Web APIs, Second Edition
A path parameter is a variable in a resource path that supplies an identifier or other value needed to identify the addressed resource.
- How it is used
- Identifies resources and expresses parent-child relationships in REST API paths.
- How deep it goes
- Explains notation, placement, hierarchy, uniqueness, OpenAPI declaration, statuses, and compatibility trade-offs.
- Examples
- Uses library calls, product collections, banking hierarchies, HTTP requests, and OpenAPI listings.
- What you can do after
- Designs and documents identifiable, hierarchical API resources with appropriate HTTP and OpenAPI parameter placement.
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Learn Go with Pocket-Sized Projects
A path parameter is a required value encoded as part of a URL path and used to identify or select a resource.
- How it is used
- Uses a URL path value to identify a particular game or habit for an HTTP endpoint.
- How deep it goes
- Works through route registration, value extraction, missing-value checks, and handler tests without examining router internals.
- Examples
- Uses `/games/{id}`, a multi-wildcard user-and-game route, and a `/tick/{habitID}` link with handler tests.
- What you can do after
- Apply it via Go net/http to register resource-specific routes, read their identifiers, and test handlers.
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ASP.NET Core in Action, 3e
A route parameter is a named variable embedded in a URL pattern whose value is extracted from a matching request path.
- How it is used
- Maps multiple request URLs to one endpoint while extracting variable path values for handler logic.
- How deep it goes
- Defines required, optional, and default parameters with examples, while deferring broader routing mechanics and syntax.
- Examples
- Uses a people-search API, product-category URLs, optional product identifiers, and Razor Page product paths.
- What you can do after
- Build it from scratch by declaring named URL variables and consuming their bound values in minimal API handlers.
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Pro ASP.NET Core 7, Tenth Edition
A route segment variable is a named placeholder in a route pattern that captures a value supplied by a URL path segment.
- How it is used
- Uses named URL placeholders to pass path values from ASP.NET Core routing to endpoints.
- How deep it goes
- Works through route registration, value access, split-segment matching, and a matching pitfall without detailing the routing algorithm.
- Examples
- Tests three-segment paths, filename extensions, capital lookups, and product-ID URLs.
- What you can do after
- Apply it via ASP.NET Core routing to capture path values for endpoint logic and page or component parameters.
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Pro Angular 16
A route parameter is a value supplied through a URL at runtime and made available to the route's navigation or component logic.
- How it is used
- Consolidates URLs for one component while passing values that select its behavior.
- How deep it goes
- Works through matching, named retrieval, input binding, and dynamic links without examining router internals.
- Examples
- Uses create-and-edit form URLs, an edit link containing a product ID, and administration routes with mode and ID parameters.
- What you can do after
- Apply it via Angular Router to consolidate routes, read URL values, and populate a form for a selected product.
Rust Servers, Services, and Apps
A URL path parameter is a variable value embedded in a URL path and supplied to the operation selected by that route.
- How it is used
- Uses URL segments to select resources and deliver typed identifiers to Actix handler functions.
- How deep it goes
- Explains route declarations, typed extraction, filtering, database calls, and manual tests, while deferring exhaustive success and failure coverage.
- Examples
- Uses `/courses/1`, `/courses/1/1`, tuple extraction, course filtering, tutor lookup, and Actix handler tests.
- What you can do after
- Apply via Actix by declaring typed path placeholders, extracting values, and passing them to filtering or database operations.
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Related concepts
- url pathpart of · A URL path is the hierarchical component of a URL that identifies a resource or route within its host.
- parametercontrasts with · A model parameter is a numerical value, such as a weight or bias, that is learned or set to determine how a model computes outputs.
- optional segmentincludes · An optional segment is a route-pattern segment that may be omitted while still allowing a URL to match the route.
- parameters listpart of · A parameters list is an OpenAPI collection of parameter definitions declared at the path level and applicable to operations under that path.
- URL patternused by · A URL pattern is a routing specification that determines which incoming URL or request a handler or destination matches.
- unique identifierkind of · A unique identifier is a value or name that distinguishes an entity or record from others within a defined scope or namespace.
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