BREAKING CHANGE: move Uncloud API socket to /run/uncloud/api/uncloud.sock, activate it by systemd socket unit

internal/daemon/daemon_test.go

@@ -0,0 +1,71 @@
+package daemon
+
+import (
+	"net"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestSelectActivatedListener(t *testing.T) {
+	t.Run("no activated listeners", func(t *testing.T) {
+		listener, err := selectActivatedListener(nil)
+		require.NoError(t, err)
+		assert.Nil(t, listener)
+	})
+
+	t.Run("only listener regardless of name", func(t *testing.T) {
+		activated := testListener(t)
+
+		listener, err := selectActivatedListener(map[string][]net.Listener{"another.socket": {activated}})
+		require.NoError(t, err)
+		assert.Same(t, activated, listener)
+	})
+
+	t.Run("named listener when multiple", func(t *testing.T) {
+		activated := testListener(t)
+		extra := testListener(t)
+
+		listener, err := selectActivatedListener(map[string][]net.Listener{
+			systemdSocketUnit: {activated},
+			"another.socket":  {extra},
+		})
+		require.NoError(t, err)
+		assert.Same(t, activated, listener)
+		assert.Error(t, extra.Close())
+	})
+
+	t.Run("multiple listeners without expected name", func(t *testing.T) {
+		first := testListener(t)
+		second := testListener(t)
+
+		listener, err := selectActivatedListener(map[string][]net.Listener{
+			"first.socket":  {first},
+			"second.socket": {second},
+		})
+		require.ErrorContains(t, err, "expected one systemd-activated socket")
+		assert.Nil(t, listener)
+	})
+
+	t.Run("multiple listeners under expected name", func(t *testing.T) {
+		first := testListener(t)
+		second := testListener(t)
+
+		listener, err := selectActivatedListener(map[string][]net.Listener{
+			systemdSocketUnit: {first, second},
+		})
+		require.ErrorContains(t, err, "expected one systemd-activated socket")
+		assert.Nil(t, listener)
+	})
+}
+
+func testListener(t *testing.T) net.Listener {
+	t.Helper()
+
+	listener, err := net.Listen("tcp", "127.0.0.1:0")
+	require.NoError(t, err)
+	t.Cleanup(func() { _ = listener.Close() })
+
+	return listener
+}