test: unit test for request cache of stream server

Signed-off-by: YaoZengzeng <[email protected]>

cri/stream/request_cache_test.go

@@ -0,0 +1,75 @@
+package stream
+
+import (
+	"testing"
+)
+
+// TODO: use fake clock to test gc of request cache.
+
+func TestRequestCacheBasic(t *testing.T) {
+	var tokens []string
+	r := NewRequestCache()
+
+	n := 10
+	for i := 0; i < n; i++ {
+		token, err := r.Insert(i)
+		if err != nil {
+			t.Fatalf("unexpected error when inserting the request: %v", err)
+		}
+		tokens = append(tokens, token)
+	}
+
+	for i := 0; i < n; i++ {
+		req, found := r.Consume(tokens[i])
+		if !found {
+			t.Fatalf("unexpected error when comsuming the cached request")
+		}
+		r, ok := req.(int)
+		if !ok {
+			t.Fatalf("the type of cached request has been changed")
+		}
+		if r != i {
+			t.Fatalf("the value of cached request has been changed")
+		}
+	}
+}
+
+func TestRequestCacheNonExist(t *testing.T) {
+	r := NewRequestCache()
+	token := "non-exist"
+	_, found := r.Consume(token)
+	if found {
+		t.Fatalf("should not find the request that not exist")
+	}
+}
+
+func TestRequestCacheTokenUnique(t *testing.T) {
+	r := NewRequestCache()
+	tokens := make(map[string]bool)
+	for i := 0; i < MaxInFlight; i++ {
+		token, err := r.Insert(i)
+		if err != nil {
+			t.Fatalf("unexpected error when inserting the request: %v", err)
+		}
+		if tokens[token] {
+			t.Fatalf("the returned token should be unique")
+		}
+		tokens[token] = true
+	}
+}
+
+func TestRequestCacheMaxInFlight(t *testing.T) {
+	r := NewRequestCache()
+
+	var i int
+	for i = 0; i < MaxInFlight; i++ {
+		_, err := r.Insert(i)
+		if err != nil {
+			t.Fatalf("unexpected error when inserting the request: %v", err)
+		}
+	}
+	_, err := r.Insert(i)
+	if err == nil {
+		t.Fatalf("should report error when there are too many cached request")
+	}
+}