dashboard: use context variables for mocking

Currently we use context.Context values themselves, but that limits the
ability to derive contexts during the request processing. Also, the race
detector is reporting a data race during the `reflect.DeepEqual`
comparison.

1 files changed, 25 insertions, 9 deletions

diff --git a/dashboard/app/util_test.go b/dashboard/app/util_test.go
index a008015a0..af9bbc2e3 100644
--- a/dashboard/app/util_test.go
+++ b/dashboard/app/util_test.go
@@ -25,7 +25,6 @@ import (
 	"github.com/google/go-cmp/cmp"
 	"github.com/google/syzkaller/dashboard/dashapi"
 	"golang.org/x/net/context"
-	"google.golang.org/appengine/v2"
 	"google.golang.org/appengine/v2/aetest"
 	db "google.golang.org/appengine/v2/datastore"
 	"google.golang.org/appengine/v2/log"
@@ -70,14 +69,14 @@ func NewCtx(t *testing.T) *Ctx {
 	c := &Ctx{
 		t:          t,
 		inst:       inst,
-		ctx:        appengine.NewContext(r),
 		mockedTime: time.Date(2000, 1, 1, 0, 0, 0, 0, time.UTC),
 		emailSink:  make(chan *aemail.Message, 100),
 	}
 	c.client = c.makeClient(client1, password1, true)
 	c.client2 = c.makeClient(client2, password2, true)
 	c.publicClient = c.makeClient(clientPublicEmail, keyPublicEmail, true)
-	registerContext(r, c)
+	c.ctx = registerRequest(r, c).Context()
+
 	return c
 }
 
@@ -246,7 +245,7 @@ func (c *Ctx) httpRequest(method, url, body string, access AccessLevel) (*httpte
 	if err != nil {
 		c.t.Fatal(err)
 	}
-	registerContext(r, c)
+	r = registerRequest(r, c)
 	if access == AccessAdmin || access == AccessUser {
 		user := &user.User{
 			Email:      "user@syzkaller.com",
@@ -374,7 +373,7 @@ type apiClient struct {
 
 func (c *Ctx) makeClient(client, key string, failOnErrors bool) *apiClient {
 	doer := func(r *http.Request) (*http.Response, error) {
-		registerContext(r, c)
+		r = registerRequest(r, c)
 		w := httptest.NewRecorder()
 		http.DefaultServeMux.ServeHTTP(w, r)
 		res := &http.Response{
@@ -549,26 +548,33 @@ func initMocks() {
 
 // Machinery to associate mocked time with requests.
 type RequestMapping struct {
-	c   context.Context
+	id  int
 	ctx *Ctx
 }
 
 var (
 	requestMu       sync.Mutex
+	requestNum      int
 	requestContexts []RequestMapping
 )
 
-func registerContext(r *http.Request, c *Ctx) {
+func registerRequest(r *http.Request, c *Ctx) *http.Request {
 	requestMu.Lock()
 	defer requestMu.Unlock()
-	requestContexts = append(requestContexts, RequestMapping{appengine.NewContext(r), c})
+
+	requestNum++
+	newContext := context.WithValue(r.Context(), requestIDKey, requestNum)
+	newRequest := r.WithContext(newContext)
+	requestContexts = append(requestContexts, RequestMapping{requestNum, c})
+	return newRequest
 }
 
 func getRequestContext(c context.Context) *Ctx {
 	requestMu.Lock()
 	defer requestMu.Unlock()
+	reqID := getRequestID(c)
 	for _, m := range requestContexts {
-		if reflect.DeepEqual(c, m.c) {
+		if m.id == reqID {
 			return m.ctx
 		}
 	}
@@ -588,3 +594,13 @@ func unregisterContext(c *Ctx) {
 	}
 	requestContexts = requestContexts[:n]
 }
+
+const requestIDKey = "test_request_id"
+
+func getRequestID(c context.Context) int {
+	val, ok := c.Value(requestIDKey).(int)
+	if !ok {
+		panic("the context did not come from a test")
+	}
+	return val
+}