add support for v2 assignment overrides endpoint in fake server

Makefile

@@ -1,6 +1,6 @@
 SHELL = /bin/sh
 
-VERSION=1.1.2
+VERSION=1.1.3
 BUILD=`git rev-parse HEAD`
 
 LDFLAGS=-ldflags "-w -s \

fakeserver/routes.go

@@ -26,6 +26,11 @@ type v1Assignment struct {
 	Unsynced  bool   `json:"unsynced"`
 }
 
+// v2AssignmentOverrideRequestBody is the JSON input for the V2 assignment override endpoint
+type v2AssignmentOverrideRequestBody struct {
+	Assignments []v1Assignment `json:"assignments"`
+}
+
 // v1VisitorConfig is the JSON output type for V1 visitor_config endpoints
 type v1VisitorConfig struct {
 	Splits  map[string]*splits.Weights `json:"splits"`
@@ -112,6 +117,10 @@ func (s *server) routes() {
 		"/api/v1/assignment_override",
 		postV1AssignmentOverride,
 	)
+	s.handlePostReturnNoContent(
+		"/api/v2/visitors/{v}/assignment_overrides",
+		postV2AssignmentOverride,
+	)
 	s.handleGet(
 		"/api/v1/apps/{a}/versions/{v}/builds/{b}/visitors/{id}/config",
 		getV1AppVisitorConfig,
@@ -257,6 +266,35 @@ func postV1AssignmentOverride(r *http.Request) error {
 	return nil
 }
 
+func postV2AssignmentOverride(r *http.Request) error {
+	var assignments []v1Assignment
+	contentType := r.Header.Get("content-type")
+	switch {
+	case strings.HasPrefix(contentType, "application/json"):
+		requestBytes, err := ioutil.ReadAll(r.Body)
+		if err != nil {
+			return err
+		}
+		var assignmentBody v2AssignmentOverrideRequestBody
+		err = json.Unmarshal(requestBytes, &assignmentBody)
+		if err != nil {
+			return err
+		}
+		assignments = assignmentBody.Assignments
+	default:
+		return fmt.Errorf("got unexpected content type %s", contentType)
+	}
+	storedAssignments, err := fakeassignments.Read()
+	for _, assignment := range assignments {
+		(*storedAssignments)[assignment.SplitName] = assignment.Variant
+	}
+	err = fakeassignments.Write(storedAssignments)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
 func getV1AppVisitorConfig() (interface{}, error) {
 	isplitRegistry, err := getV1SplitRegistry()
 	splitRegistry := isplitRegistry.(map[string]*splits.Weights)

fakeserver/server_test.go

@@ -1,6 +1,7 @@
 package fakeserver
 
 import (
+	"bytes"
 	"io/ioutil"
 	"log"
 	"net/http"
@@ -27,6 +28,10 @@ splits:
   weights:
     control: 60
     treatment: 40
+- name: test.test2_experiment
+  weights:
+    control: 60
+    treatment: 40
 `
 
 func TestMain(m *testing.M) {
@@ -150,3 +155,40 @@ func TestPersistAssignment(t *testing.T) {
 		require.Equal(t, "control", (*assignments)["test.test_experiment"])
 	})
 }
+
+func TestPersistAssignmentV2(t *testing.T) {
+	os.Remove("testdata/assignments.yml")
+
+	t.Run("it persists assignments to yaml", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		h := createHandler()
+
+		overrides := v2AssignmentOverrideRequestBody{
+			Assignments: []v1Assignment{
+				v1Assignment{
+					SplitName: "test.test_experiment",
+					Variant:   "control",
+				},
+				v1Assignment{
+					SplitName: "test.test2_experiment",
+					Variant:   "treatment",
+				},
+			},
+		}
+		data, err := json.Marshal(overrides)
+		require.Nil(t, err)
+
+		request := httptest.NewRequest("POST", "/api/v2/visitors/1/assignment_overrides", bytes.NewReader(data))
+		request.Header.Add("Content-Type", "application/json")
+		request.Header.Add("Content-Length", strconv.Itoa(len(data)))
+
+		h.ServeHTTP(w, request)
+
+		require.Equal(t, http.StatusNoContent, w.Code)
+
+		assignments, err := fakeassignments.Read()
+		require.Nil(t, err)
+		require.Equal(t, "control", (*assignments)["test.test_experiment"])
+		require.Equal(t, "treatment", (*assignments)["test.test2_experiment"])
+	})
+}