Refactor routing & pipeline dsl (amberframework#17)

* Move Router & Pipeline DSLs under Amber::Support::DSL module
* Make the DSLs tied to a particular Router/Pipeline instance
* Fix router spec

spec/amber/pipe/router_spec.cr

@@ -6,7 +6,7 @@ module Amber
       describe "#call" do
         it "raises exception when route not found" do
           router = Router.instance
-          request = HTTP::Request.new("GET", "/hello/world")
+          request = HTTP::Request.new("GET", "/bad/route")
 
           expect_raises Exceptions::RouteNotFound do
             create_request_and_return_io(router, request)

src/amber.cr

@@ -58,12 +58,16 @@ module Amber
       with self yield self
     end
 
-    def routes(&block)
-      router.draw(&block)
+    macro routes
+      router.draw do
+        {{yield}}
+      end
     end
 
-    def pipeline(valve : Symbol, &block)
-      handler.build valve, &block
+    macro pipeline(valve)
+      handler.build {{valve}} do
+        {{yield}}
+      end
     end
 
     def handler

src/amber/pipe/pipeline.cr

@@ -28,7 +28,7 @@ module Amber
       def build(valve : Symbol, &block)
         @valve = valve
         @pipeline[@valve] = [] of HTTP::Handler unless @pipeline.key? @valve
-        with self yield
+        with Support::DSL::Pipeline.new(self) yield
       end
 
       def plug(pipe : HTTP::Handler)

src/amber/pipe/router.cr

@@ -25,7 +25,7 @@ module Amber
 
       # This registers all the routes for the application
       def draw
-        with self yield
+        with Support::DSL::Router.new(self) yield
       end
 
       def add(route : Route)
@@ -46,7 +46,7 @@ module Amber
       end
 
       private def merge_params(params, context)
-        params.each { |k,v| context.params.add(k.to_s, v) }
+        params.each { |k, v| context.params.add(k.to_s, v) }
       end
 
       private def match(http_verb, resource) : Radix::Result(Amber::Route)

src/amber/support/dsls.cr

@@ -0,0 +1,26 @@
+module Amber::Support::DSL
+  record Pipeline, pipeline : Pipe::Pipeline do
+    def plug(pipe)
+      pipeline.plug pipe
+    end
+  end
+
+  record Router, router : Pipe::Router do
+    macro route(verb, resource, controller, handler, pipeline)
+      %ctrl = {{controller.id}}.new
+      %action = ->%ctrl.{{handler.id}}
+      %verb = {{verb.upcase.id.stringify}}
+      %route = Amber::Route.new(%verb, {{resource}}, %ctrl, %action, {{pipeline}})
+
+      router.add(%route)
+    end
+
+    {% for verb in {:get, :post, :put, :delete, :options, :head, :trace, :connect} %}
+
+      macro {{verb.id}}(*args)
+        route {{verb}}, \{{*args}}
+      end
+
+    {% end %}
+  end
+end