feat: runtime manager

rtmanager/internal/app/app_test.go

@@ -0,0 +1,137 @@
+package app
+
+import (
+	"context"
+	"errors"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"galaxy/rtmanager/internal/config"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+type fakeComponent struct {
+	runErr       error
+	shutdownErr  error
+	runHook      func(context.Context) error
+	shutdownHook func(context.Context) error
+	runCount     atomic.Int32
+	downCount    atomic.Int32
+	blockForCtx  bool
+}
+
+func (component *fakeComponent) Run(ctx context.Context) error {
+	component.runCount.Add(1)
+	if component.runHook != nil {
+		return component.runHook(ctx)
+	}
+	if component.blockForCtx {
+		<-ctx.Done()
+		return ctx.Err()
+	}
+
+	return component.runErr
+}
+
+func (component *fakeComponent) Shutdown(ctx context.Context) error {
+	component.downCount.Add(1)
+	if component.shutdownHook != nil {
+		return component.shutdownHook(ctx)
+	}
+
+	return component.shutdownErr
+}
+
+func newCfg() config.Config {
+	return config.Config{ShutdownTimeout: time.Second}
+}
+
+func TestAppRunWithoutComponentsBlocksUntilContextDone(t *testing.T) {
+	t.Parallel()
+
+	app := New(newCfg())
+
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+
+	require.NoError(t, app.Run(ctx))
+}
+
+func TestAppRunReturnsOnContextCancel(t *testing.T) {
+	t.Parallel()
+
+	component := &fakeComponent{blockForCtx: true}
+	app := New(newCfg(), component)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	go func() {
+		time.Sleep(10 * time.Millisecond)
+		cancel()
+	}()
+
+	require.NoError(t, app.Run(ctx))
+	assert.EqualValues(t, 1, component.runCount.Load())
+	assert.EqualValues(t, 1, component.downCount.Load())
+}
+
+func TestAppRunPropagatesComponentFailure(t *testing.T) {
+	t.Parallel()
+
+	failure := errors.New("boom")
+	component := &fakeComponent{runErr: failure}
+	app := New(newCfg(), component)
+
+	err := app.Run(context.Background())
+	require.Error(t, err)
+	require.ErrorIs(t, err, failure)
+	assert.EqualValues(t, 1, component.downCount.Load())
+}
+
+func TestAppRunFailsOnNilContext(t *testing.T) {
+	t.Parallel()
+
+	app := New(newCfg())
+	var ctx context.Context
+	require.Error(t, app.Run(ctx))
+}
+
+func TestAppRunFailsOnNonPositiveShutdownTimeout(t *testing.T) {
+	t.Parallel()
+
+	app := New(config.Config{}, &fakeComponent{})
+	require.Error(t, app.Run(context.Background()))
+}
+
+func TestAppRunFailsOnNilComponent(t *testing.T) {
+	t.Parallel()
+
+	app := New(newCfg(), nil)
+	require.Error(t, app.Run(context.Background()))
+}
+
+func TestAppRunFlagsCleanExitBeforeShutdown(t *testing.T) {
+	t.Parallel()
+
+	component := &fakeComponent{}
+	app := New(newCfg(), component)
+
+	err := app.Run(context.Background())
+	require.Error(t, err)
+	require.True(t, contains(err.Error(), "exited without error"))
+}
+
+func contains(haystack, needle string) bool {
+	return len(needle) == 0 || (len(haystack) >= len(needle) && (haystack == needle || index(haystack, needle) >= 0))
+}
+
+func index(haystack, needle string) int {
+	for i := 0; i+len(needle) <= len(haystack); i++ {
+		if haystack[i:i+len(needle)] == needle {
+			return i
+		}
+	}
+	return -1
+}