Make requirements and anchor first-class endpoint inputs

`route`'s documented options `requirements:` and `anchor:` are now explicit
keyword arguments rather than opaque keys in the `route_options` bag, with
`**route_options` still catching any custom options. They travel as their
own endpoint inputs (`Grape::Endpoint::Options` gains `:requirements` and
`:anchor` members; `Grape::Endpoint.new` gains matching keywords) and
`to_routes` reads them via `config.requirements` / `config.anchor` instead
of `route_options[...]`. The verb methods forward `**options` unchanged, so
`get(':id', requirements: {...}, anchor: false)` still works.

Like `params`, they no longer appear in `route.options`; the effective value
comes from the `route.requirements` / `route.anchor` readers. Mounts pass
`anchor: false` as a keyword too.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: ericproulx

CHANGELOG.md

@@ -13,6 +13,7 @@
 * [#2783](https://github.com/ruby-grape/grape/pull/2783): Read a route's `version`, `anchor` and `requirements` from its pattern instead of storing them again on the route - [@ericproulx](https://github.com/ericproulx).
 * [#2784](https://github.com/ruby-grape/grape/pull/2784): Move HEAD route creation into `Grape::Router::Route#to_head` - [@ericproulx](https://github.com/ericproulx).
 * [#2785](https://github.com/ruby-grape/grape/pull/2785): Make route `params` a first-class endpoint input and split `Grape::Router::Route#params` into `#params` (declared definitions) and `#params_for(input)` (extracted values) - [@ericproulx](https://github.com/ericproulx).
+* [#2786](https://github.com/ruby-grape/grape/pull/2786): Make route `requirements` and `anchor` explicit keyword arguments and first-class endpoint inputs instead of opaque `route_options` keys - [@ericproulx](https://github.com/ericproulx).
 * Your contribution here.
 
 #### Fixes

UPGRADING.md

@@ -52,7 +52,7 @@ route.anchor        # => true
 route.settings      # => { ... }
 ```
 
-What changed is the raw bag. `route.options` now holds only what was declared for the route, so it no longer carries the *computed* values for these keys — `route.options[:version]`, `[:namespace]`, `[:prefix]` and `[:settings]` return `nil`. Nothing in Grape or grape-swagger read them that way (grape-swagger uses the `route.prefix` and `route.settings` readers). For `requirements` and `anchor`, which can be supplied as route options (e.g. a mount's `anchor: false`), any explicitly declared value still appears in `route.options`; the effective value always comes from the reader.
+What changed is the raw bag. `route.options` now holds only what was declared for the route, so it no longer carries the *computed* values for these keys — `route.options[:version]`, `[:namespace]`, `[:prefix]` and `[:settings]` return `nil`. Nothing in Grape or grape-swagger read them that way (grape-swagger uses the `route.prefix` and `route.settings` readers). `requirements` and `anchor` — which can be supplied as route options (e.g. a mount's `anchor: false`) — are covered separately below: they too are now first-class endpoint inputs and likewise no longer appear in `route.options`. The effective value always comes from the reader.
 
 #### `Grape::Endpoint` no longer accepts a `format:` keyword
 
@@ -75,6 +75,10 @@ The no-argument form is unchanged — grape-swagger and other documentation cons
 
 A route's declared params were previously carried inside the `route_options` bag and reachable as `route.options[:params]`. They are now composed into their own endpoint input (`Grape::Endpoint::Options` gains a `:params` member and `Grape::Endpoint.new` a `params:` keyword) and exposed only through `route.params`. `route.options[:params]` now returns `nil`. Nothing in Grape or grape-swagger read it that way — grape-swagger uses the `route.params` method — so this only affects code that reached into the options Hash for params directly.
 
+#### `requirements` and `anchor` are first-class endpoint inputs, no longer in `route.options`
+
+Like `params` above, a route's `requirements` and `anchor` were previously carried inside the `route_options` bag. They are now composed into their own endpoint inputs (`Grape::Endpoint::Options` gains `:requirements` and `:anchor` members, and `Grape::Endpoint.new` gains `requirements:` and `anchor:` keywords) and exposed only through the `route.requirements` and `route.anchor` readers. `route.options[:requirements]` and `route.options[:anchor]` now return `nil` — including for a mount's `anchor: false`. Nothing in Grape or grape-swagger read them that way, so this only affects code that reached into the options Hash for these keys directly.
+
 ### Upgrading to >= 3.3
 
 #### Minimum required Ruby is now 3.3

lib/grape/dsl/routing.rb

@@ -159,7 +159,7 @@ def mount(mounts, *opts)
             http_methods: :any,
             path:,
             app:,
-            route_options: { anchor: false },
+            anchor: false,
             api: self
           )
         end
@@ -170,19 +170,23 @@ def mount(mounts, *opts)
       #
       # @param methods [HTTP Verb] One or more HTTP verbs that are accepted by this route. Set to `:any` if you want any verb to be accepted.
       # @param paths [String] One or more strings representing the URL segment(s) for this route.
+      # @param requirements [Hash] Regular-expression constraints for named path params; the route matches only when every requirement is satisfied.
+      # @param anchor [Boolean] Whether the route is anchored to the whole path. Defaults to `true`; pass `false` for catch-all routes (e.g. `'/(*:path)'`).
+      # @param route_options [Hash] Any additional custom options, carried through to `route.options`.
       #
       # @example Defining a basic route.
       #   class MyAPI < Grape::API
       #     route(:any, '/hello') do
       #       {hello: 'world'}
       #     end
       #   end
-      def route(methods, paths = ['/'], route_options = {}, &)
+      def route(methods, paths = ['/'], requirements: nil, anchor: true, **route_options, &)
         http_methods = methods == :any ? '*' : methods
         endpoint_description = inheritable_setting.route[:description] || {}
 
-        # +params+ travels as its own endpoint input; the route-options bag keeps
-        # the description's other keys (+success+, +tags+, …) plus explicit options.
+        # +params+, +requirements+ and +anchor+ each travel as their own endpoint
+        # input; the route-options bag keeps the description's other keys
+        # (+success+, +tags+, …) plus any custom options.
         params = prepare_params(endpoint_description[:params])
         all_route_options = endpoint_description.except(:params)
         all_route_options.deep_merge!(route_options) if route_options.present?
@@ -193,6 +197,8 @@ def route(methods, paths = ['/'], route_options = {}, &)
           path: paths,
           api: self,
           params:,
+          requirements:,
+          anchor:,
           route_options: all_route_options,
           &
         )
@@ -204,7 +210,7 @@ def route(methods, paths = ['/'], route_options = {}, &)
 
       Grape::HTTP_SUPPORTED_METHODS.each do |supported_method|
         define_method supported_method.downcase do |path = '/', **options, &block|
-          route(supported_method, path, options, &block)
+          route(supported_method, path, **options, &block)
         end
       end
 

lib/grape/endpoint.rb

@@ -56,13 +56,17 @@ def block_to_unbound_method(block)
     #   endpoint; +nil+ for a plain block endpoint. Exposed as {#mounted_app}.
     # @param params [Hash] the declared params for this endpoint, keyed by name.
     #   Kept out of +route_options+ and read via +config.params+.
+    # @param requirements [Hash, nil] regular-expression constraints for named
+    #   path params. Read via +config.requirements+.
+    # @param anchor [Boolean] whether the route anchors to the whole path
+    #   (default +true+). Read via +config.anchor+.
     # @param options [Hash] attributes of this endpoint, normalized into a
     #   +Grape::Endpoint::Options+ value object.
     # @option options route_options [Hash]
     # @note This happens at the time of API definition, so in this context the
     # endpoint does not know if it will be mounted under a different endpoint.
     # @yield a block defining what your API should do when this endpoint is hit
-    def initialize(new_settings, http_methods:, path:, api:, app: nil, params: {}, **options, &block)
+    def initialize(new_settings, http_methods:, path:, api:, app: nil, params: {}, requirements: nil, anchor: true, **options, &block)
       self.inheritable_setting = new_settings.point_in_time_copy
 
       # now +namespace_stackable(:declared_params)+ contains all params defined for
@@ -75,7 +79,7 @@ def initialize(new_settings, http_methods:, path:, api:, app: nil, params: {}, *
       inheritable_setting.namespace_inheritable[:default_error_status] ||= 500
 
       @options = options
-      @config = Options.new(http_methods:, path:, api:, app:, params:, **options)
+      @config = Options.new(http_methods:, path:, api:, app:, params:, requirements:, anchor:, **options)
       # +:app+ is still surfaced on the public options Hash for backwards
       # compatibility (e.g. grape-swagger); prefer the +mounted_app+ reader.
       @options[:app] = app if app
@@ -289,8 +293,8 @@ def to_routes
       forward_match = config.app && !config.app.respond_to?(:inheritable_setting)
       version = prepare_version(inheritable_setting.namespace_inheritable[:version])
       prefix = inheritable_setting.namespace_inheritable[:root_prefix]
-      requirements = prepare_routes_requirements(route_options[:requirements])
-      anchor = route_options.fetch(:anchor, true)
+      requirements = prepare_routes_requirements(config.requirements)
+      anchor = config.anchor
       settings = inheritable_setting.route.except(:declared_params, :saved_validations)
 
       config.http_methods.flat_map do |method|

lib/grape/endpoint/options.rb

@@ -6,8 +6,8 @@ class Endpoint
     # +Grape::Endpoint.new+. Internal to {Grape::Endpoint}, which builds it
     # from the +**options+ Hash in #initialize so the public +options+ reader
     # stays a plain Hash for downstream gems (e.g. grape-swagger).
-    Options = Data.define(:path, :http_methods, :api, :route_options, :app, :params) do
-      def initialize(path:, http_methods:, api:, route_options: {}, app: nil, params: {})
+    Options = Data.define(:path, :http_methods, :api, :route_options, :app, :params, :requirements, :anchor) do
+      def initialize(path:, http_methods:, api:, route_options: {}, app: nil, params: {}, requirements: nil, anchor: true)
         path = Array(path)
         path << '/' if path.empty?
         http_methods = Array(http_methods)

spec/grape/dsl/routing_spec.rb

@@ -159,10 +159,12 @@ class << self
         expect(endpoint_options[:path]).to eq '/foo'
         expect(endpoint_options[:api]).to eq subject
         expect(endpoint_options[:params]).to eq(nuz: 'naz')
+        expect(endpoint_options[:requirements]).to eq(id: /\d/)
+        expect(endpoint_options[:anchor]).to be(false)
         expect(endpoint_options[:route_options]).to eq(foo: 'bar', fiz: 'baz')
       end.and_yield
 
-      subject.route(:get, '/foo', { foo: 'bar' }, &proc {})
+      subject.route(:get, '/foo', requirements: { id: /\d/ }, anchor: false, foo: 'bar', &proc {})
     end
   end