initial implementation

pkg/router/chain_test.go

@@ -0,0 +1,50 @@
+package router
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"git.juancwu.dev/juancwu/lightmux/pkg/middleware"
+)
+
+func tagMW(log *[]string, tag string) middleware.Middleware {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			*log = append(*log, tag+":before")
+			next.ServeHTTP(w, r)
+			*log = append(*log, tag+":after")
+		})
+	}
+}
+
+func TestChainOrder(t *testing.T) {
+	var log []string
+	h := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		log = append(log, "handler")
+	})
+
+	wrapped := chain(h,
+		[]middleware.Middleware{tagMW(&log, "g1"), tagMW(&log, "g2")},
+		[]middleware.Middleware{tagMW(&log, "r1"), tagMW(&log, "r2")},
+	)
+
+	req := httptest.NewRequest(http.MethodGet, "/", nil)
+	wrapped.ServeHTTP(httptest.NewRecorder(), req)
+
+	want := "g1:before,g2:before,r1:before,r2:before,handler,r2:after,r1:after,g2:after,g1:after"
+	if got := strings.Join(log, ","); got != want {
+		t.Errorf("order:\n got %s\nwant %s", got, want)
+	}
+}
+
+func TestChainNoMiddlewares(t *testing.T) {
+	called := false
+	h := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { called = true })
+	wrapped := chain(h, nil, nil)
+	wrapped.ServeHTTP(httptest.NewRecorder(), httptest.NewRequest(http.MethodGet, "/", nil))
+	if !called {
+		t.Fatal("handler not called")
+	}
+}