agent/cache: send the RefreshTimeout into the backend fetch

agent/cache/cache.go

@@ -134,6 +134,10 @@ type RegisterOptions struct {
 // This makes the type available for Get but does not automatically perform
 // any prefetching. In order to populate the cache, Get must be called.
 func (c *Cache) RegisterType(n string, typ Type, opts *RegisterOptions) {
+	if opts == nil {
+		opts = &RegisterOptions{}
+	}
+
 	c.typesLock.Lock()
 	defer c.typesLock.Unlock()
 	c.types[n] = typeEntry{Type: typ, Opts: opts}
@@ -290,6 +294,7 @@ func (c *Cache) fetch(t, key string, r Request) (<-chan struct{}, error) {
 		// Start building the new entry by blocking on the fetch.
 		result, err := tEntry.Type.Fetch(FetchOptions{
 			MinIndex: entry.Index,
+			Timeout:  tEntry.Opts.RefreshTimeout,
 		}, r)
 
 		if err == nil {
@@ -336,7 +341,7 @@ func (c *Cache) fetch(t, key string, r Request) (<-chan struct{}, error) {
 
 		// If refresh is enabled, run the refresh in due time. The refresh
 		// below might block, but saves us from spawning another goroutine.
-		if tEntry.Opts != nil && tEntry.Opts.Refresh {
+		if tEntry.Opts.Refresh {
 			c.refresh(tEntry.Opts, t, key, r)
 		}
 	}()

agent/cache/cache_test.go

@@ -336,6 +336,39 @@ func TestCacheGet_periodicRefresh(t *testing.T) {
 	TestCacheGetChResult(t, resultCh, 12)
 }
 
+// Test that the backend fetch sets the proper timeout.
+func TestCacheGet_fetchTimeout(t *testing.T) {
+	t.Parallel()
+
+	require := require.New(t)
+
+	typ := TestType(t)
+	defer typ.AssertExpectations(t)
+	c := TestCache(t)
+
+	// Register the type with a timeout
+	timeout := 10 * time.Minute
+	c.RegisterType("t", typ, &RegisterOptions{
+		RefreshTimeout: timeout,
+	})
+
+	// Configure the type
+	var actual time.Duration
+	typ.Static(FetchResult{Value: 42}, nil).Times(1).Run(func(args mock.Arguments) {
+		opts := args.Get(0).(FetchOptions)
+		actual = opts.Timeout
+	})
+
+	// Get, should fetch
+	req := TestRequest(t, RequestInfo{Key: "hello"})
+	result, err := c.Get("t", req)
+	require.Nil(err)
+	require.Equal(42, result)
+
+	// Test the timeout
+	require.Equal(timeout, actual)
+}
+
 // Test that Get partitions the caches based on DC so two equivalent requests
 // to different datacenters are automatically cached even if their keys are
 // the same.