Added urlquery middleware, resolves #174.

web/middleware/urlquery.go

@@ -0,0 +1,24 @@
+package middleware
+
+import (
+	"github.com/zenazn/goji/web"
+	"net/http"
+)
+
+// UrlQueryKey is the context key for the URL Query
+const UrlQueryKey string = "urlquery"
+
+// UrlQuery is a middleware to parse the URL Query parameters just once,
+// and store the resulting url.Values in the context.
+func UrlQuery(c *web.C, h http.Handler) http.Handler {
+	fn := func(w http.ResponseWriter, r *http.Request) {
+		if c.Env == nil {
+			c.Env = make(map[interface{}]interface{})
+		}
+		c.Env[UrlQueryKey] = r.URL.Query()
+
+		h.ServeHTTP(w, r)
+	}
+
+	return http.HandlerFunc(fn)
+}

web/middleware/urlquery_test.go

@@ -0,0 +1,53 @@
+package middleware
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"reflect"
+	"testing"
+
+	"github.com/zenazn/goji/web"
+)
+
+func testUrlQuery(r *http.Request, f func(*web.C, http.ResponseWriter, *http.Request)) *httptest.ResponseRecorder {
+	var c web.C
+
+	h := func(w http.ResponseWriter, r *http.Request) {
+		f(&c, w, r)
+	}
+	m := UrlQuery(&c, http.HandlerFunc(h))
+	w := httptest.NewRecorder()
+	m.ServeHTTP(w, r)
+
+	return w
+}
+
+func TestUrlQuery(t *testing.T) {
+	type testcase struct {
+		url            string
+		expectedParams url.Values
+	}
+
+	// we're not testing url.Query() here, but rather that the results of the query
+	// appear in the context
+	testcases := []testcase{
+		testcase{"/", url.Values{}},
+		testcase{"/?a=1&b=2&a=3", url.Values{"a": []string{"1", "3"}, "b": []string{"2"}}},
+		testcase{"/?x=1&y=2&z=3#freddyishere", url.Values{"x": []string{"1"}, "y": []string{"2"}, "z": []string{"3"}}},
+	}
+
+	for _, tc := range testcases {
+		r, _ := http.NewRequest("GET", tc.url, nil)
+		testUrlQuery(r,
+			func(c *web.C, w http.ResponseWriter, r *http.Request) {
+				params := c.Env[UrlQueryKey].(url.Values)
+				if !reflect.DeepEqual(params, tc.expectedParams) {
+					t.Errorf("GET %s, UrlQuery middleware found %v, should be %v", tc.url, params, tc.expectedParams)
+				}
+
+				w.Write([]byte{'h', 'i'})
+			},
+		)
+	}
+}