rename ngin to rest

rest/handler/sheddinghandler_test.go

@@ -0,0 +1,105 @@
+package handler
+
+import (
+	"io/ioutil"
+	"log"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"zero/core/load"
+	"zero/core/stat"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func init() {
+	log.SetOutput(ioutil.Discard)
+}
+
+func TestSheddingHandlerAccept(t *testing.T) {
+	metrics := stat.NewMetrics("unit-test")
+	shedder := mockShedder{
+		allow: true,
+	}
+	sheddingHandler := SheddingHandler(shedder, metrics)
+	handler := sheddingHandler(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("X-Test", "test")
+		_, err := w.Write([]byte("content"))
+		assert.Nil(t, err)
+	}))
+
+	req := httptest.NewRequest(http.MethodGet, "http://localhost", nil)
+	req.Header.Set("X-Test", "test")
+	resp := httptest.NewRecorder()
+	handler.ServeHTTP(resp, req)
+	assert.Equal(t, http.StatusOK, resp.Code)
+	assert.Equal(t, "test", resp.Header().Get("X-Test"))
+	assert.Equal(t, "content", resp.Body.String())
+}
+
+func TestSheddingHandlerFail(t *testing.T) {
+	metrics := stat.NewMetrics("unit-test")
+	shedder := mockShedder{
+		allow: true,
+	}
+	sheddingHandler := SheddingHandler(shedder, metrics)
+	handler := sheddingHandler(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusServiceUnavailable)
+	}))
+
+	req := httptest.NewRequest(http.MethodGet, "http://localhost", nil)
+	resp := httptest.NewRecorder()
+	handler.ServeHTTP(resp, req)
+	assert.Equal(t, http.StatusServiceUnavailable, resp.Code)
+}
+
+func TestSheddingHandlerReject(t *testing.T) {
+	metrics := stat.NewMetrics("unit-test")
+	shedder := mockShedder{
+		allow: false,
+	}
+	sheddingHandler := SheddingHandler(shedder, metrics)
+	handler := sheddingHandler(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	}))
+
+	req := httptest.NewRequest(http.MethodGet, "http://localhost", nil)
+	resp := httptest.NewRecorder()
+	handler.ServeHTTP(resp, req)
+	assert.Equal(t, http.StatusServiceUnavailable, resp.Code)
+}
+
+func TestSheddingHandlerNoShedding(t *testing.T) {
+	metrics := stat.NewMetrics("unit-test")
+	sheddingHandler := SheddingHandler(nil, metrics)
+	handler := sheddingHandler(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	}))
+
+	req := httptest.NewRequest(http.MethodGet, "http://localhost", nil)
+	resp := httptest.NewRecorder()
+	handler.ServeHTTP(resp, req)
+	assert.Equal(t, http.StatusOK, resp.Code)
+}
+
+type mockShedder struct {
+	allow bool
+}
+
+func (s mockShedder) Allow() (load.Promise, error) {
+	if s.allow {
+		return mockPromise{}, nil
+	} else {
+		return nil, load.ErrServiceOverloaded
+	}
+}
+
+type mockPromise struct {
+}
+
+func (p mockPromise) Pass() {
+}
+
+func (p mockPromise) Fail() {
+}