callback resolver to allow fast implementations

Author: sharpner

resolver.go

@@ -1,5 +1,29 @@
 package api2go
 
+import "net/http"
+
+type callbackResolver struct {
+	callback func(r http.Request) string
+	r        http.Request
+}
+
+//NewCallbackResolver handles each resolve via
+//your provided callback func
+func NewCallbackResolver(callback func(http.Request) string) URLResolver {
+	return &callbackResolver{callback: callback}
+}
+
+//GetBaseURL calls the callback given in the constructor method
+//to implement `URLResolver`
+func (c callbackResolver) GetBaseURL() string {
+	return c.callback(c.r)
+}
+
+//SetRequest to implement `RequestAwareURLResolver`
+func (c *callbackResolver) SetRequest(r http.Request) {
+	c.r = r
+}
+
 //staticResolver is only used
 //for backwards compatible reasons
 //and might be removed in the future

resolver_test.go

@@ -0,0 +1,33 @@
+package api2go
+
+import (
+	"net/http"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("Resolver test", func() {
+	Context("basic function of callback resolver", func() {
+		It("works", func() {
+			callback := func(r http.Request) string {
+				if r.Header.Get("lol") != "" {
+					return "funny"
+				}
+
+				return "unfunny"
+			}
+
+			resolver := NewCallbackResolver(callback)
+			Expect(resolver.GetBaseURL()).To(Equal("unfunny"))
+			req, err := http.NewRequest("GET", "/v1/posts", nil)
+			req.Header.Set("lol", "lol")
+			Expect(err).To(BeNil())
+			requestResolver, ok := resolver.(RequestAwareURLResolver)
+			Expect(ok).To(Equal(true), "does not implement interface")
+			Expect(requestResolver.GetBaseURL()).To(Equal("unfunny"))
+			requestResolver.SetRequest(*req)
+			Expect(requestResolver.GetBaseURL()).To(Equal("funny"))
+		})
+	})
+})