add cache test

app/rest/cache_test.go

@@ -0,0 +1,54 @@
+package rest
+
+import (
+	"context"
+	"net/http"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/umputun/remark/app/store"
+)
+
+func TestLoadingCache_Get(t *testing.T) {
+	var postFnCall, coldCalls int
+	lc := NewLoadingCache(1*time.Minute, 200*time.Millisecond, func() {
+		postFnCall++
+	})
+
+	res, err := lc.Get("key", time.Minute, func() ([]byte, error) {
+		coldCalls++
+		return []byte("result"), nil
+	})
+	assert.Nil(t, err)
+	assert.Equal(t, "result", string(res))
+	assert.Equal(t, 1, coldCalls)
+	assert.Equal(t, 0, postFnCall)
+
+	res, err = lc.Get("key", time.Minute, func() ([]byte, error) {
+		coldCalls++
+		return []byte("result"), nil
+	})
+	assert.Nil(t, err)
+	assert.Equal(t, "result", string(res))
+	assert.Equal(t, 1, coldCalls)
+	assert.Equal(t, 0, postFnCall)
+
+	lc.Flush()
+	time.Sleep(100 * time.Millisecond) // let postFn to do its thing
+	assert.Equal(t, 1, postFnCall)
+}
+
+func TestLoadingCache_URLKey(t *testing.T) {
+	r, err := http.NewRequest("GET", "http://blah/123", nil)
+	assert.Nil(t, err)
+	key := URLKey(r)
+	assert.Equal(t, "http://blah/123", key)
+
+	ctx := context.Background()
+	user := store.User{Admin: true}
+	ctx = context.WithValue(ctx, ContextKey("user"), user)
+	r = r.WithContext(ctx)
+	key = URLKey(r)
+	assert.Equal(t, "admin!!http://blah/123", key)
+}