API: introduce ability to watch a VM (#351)

* API: introduce ability to watch a VM * Document ?watch=true for GET /vms/{name} in the OpenAPI specification * WatchVM: ensure that goroutine is terminated on early return with error * WatchVM: close channels on goroutine exit * WatchVM: ensure that we wait for the goroutine after additional barriers * WatchVM: ignore unexpected keys instead of throwing an error * WatchVM: perform context-aware writes to a bounded channel * WatchVM: don't forget to close errCh on goroutine exit too * WatchVM: don't close readyCh in goroutine to avoid ambiguity * WatchVM: filter out spurious KVs that signify VM deletion
2026-10-22 06:18:16 +02:00 · 2025-10-03 21:34:53 +04:00
parent cdece3149b
commit c5e0d68a3d
9 changed files with 458 additions and 6 deletions
@@ -0,0 +1,179 @@
+package store_test
+
+import (
+	"context"
+	"fmt"
+	"testing"
+	"time"
+
+	storepkg "github.com/cirruslabs/orchard/internal/controller/store"
+	"github.com/cirruslabs/orchard/internal/controller/store/badger"
+	"github.com/cirruslabs/orchard/pkg/resource/v1"
+	"github.com/stretchr/testify/require"
+	"go.uber.org/zap"
+)
+
+func TestWatchVM(t *testing.T) {
+	logger := zap.Must(zap.NewDevelopment())
+
+	testCases := []struct {
+		Name string
+		Run  func(t *testing.T, store storepkg.Store)
+	}{
+		{
+			Name: "simple-vm-already-exists",
+			Run: func(t *testing.T, store storepkg.Store) {
+				// Create a VM
+				const vmName = "test"
+
+				vm := v1.VM{
+					Meta: v1.Meta{
+						Name: vmName,
+					},
+				}
+
+				err := store.Update(func(txn storepkg.Transaction) error {
+					return txn.SetVM(vm)
+				})
+				require.NoError(t, err)
+
+				// Start watching a VM
+				ctx, cancel := context.WithTimeout(t.Context(), 10*time.Second)
+				defer cancel()
+
+				watchCh, errCh, err := store.WatchVM(ctx, vmName)
+				require.NoError(t, err)
+
+				// Ensure that a synthetic VM creation event is emitted
+				select {
+				case item := <-watchCh:
+					require.Equal(t, item.Type, storepkg.WatchMessageTypeAdded)
+				case err := <-errCh:
+					require.NoError(t, err)
+				case <-ctx.Done():
+					require.FailNow(t, "timed out waiting for ADDED watch event")
+				}
+
+				// Update the VM and ensure that a modification event is emitted
+				err = store.Update(func(txn storepkg.Transaction) error {
+					return txn.SetVM(vm)
+				})
+				require.NoError(t, err)
+
+				select {
+				case item := <-watchCh:
+					require.Equal(t, item.Type, storepkg.WatchMessageTypeModified)
+				case err := <-errCh:
+					require.NoError(t, err)
+				case <-ctx.Done():
+					require.FailNow(t, "timed out waiting for MODIFIED watch event")
+				}
+
+				// Delete the VM and ensure that a deletion event is emitted
+				err = store.Update(func(txn storepkg.Transaction) error {
+					return txn.DeleteVM(vmName)
+				})
+				require.NoError(t, err)
+
+				select {
+				case item := <-watchCh:
+					require.Equal(t, item.Type, storepkg.WatchMessageTypeDeleted)
+				case err := <-errCh:
+					require.NoError(t, err)
+				case <-ctx.Done():
+					require.FailNow(t, "timed out waiting for DELETED watch event")
+				}
+			},
+		},
+		{
+			Name: "simple-vm-not-yet-exists",
+			Run: func(t *testing.T, store storepkg.Store) {
+				// Start watching a VM
+				const vmName = "test"
+
+				ctx, cancel := context.WithTimeout(t.Context(), 10*time.Second)
+				defer cancel()
+
+				watchCh, errCh, err := store.WatchVM(ctx, vmName)
+				require.NoError(t, err)
+
+				// Create a VM
+				vm := v1.VM{
+					Meta: v1.Meta{
+						Name: vmName,
+					},
+				}
+
+				err = store.Update(func(txn storepkg.Transaction) error {
+					return txn.SetVM(vm)
+				})
+				require.NoError(t, err)
+
+				// Ensure that a VM creation event is emitted
+				select {
+				case item := <-watchCh:
+					require.Equal(t, item.Type, storepkg.WatchMessageTypeAdded)
+				case err := <-errCh:
+					require.NoError(t, err)
+				case <-ctx.Done():
+					require.FailNow(t, "timed out waiting for ADDED watch event")
+				}
+
+				// Update the VM and ensure that a modification event is emitted
+				err = store.Update(func(txn storepkg.Transaction) error {
+					return txn.SetVM(vm)
+				})
+				require.NoError(t, err)
+
+				select {
+				case item := <-watchCh:
+					require.Equal(t, item.Type, storepkg.WatchMessageTypeModified)
+				case err := <-errCh:
+					require.NoError(t, err)
+				case <-ctx.Done():
+					require.FailNow(t, "timed out waiting for MODIFIED watch event")
+				}
+
+				// Delete the VM and ensure that a deletion event is emitted
+				err = store.Update(func(txn storepkg.Transaction) error {
+					return txn.DeleteVM(vmName)
+				})
+				require.NoError(t, err)
+
+				select {
+				case item := <-watchCh:
+					require.Equal(t, item.Type, storepkg.WatchMessageTypeDeleted)
+				case err := <-errCh:
+					require.NoError(t, err)
+				case <-ctx.Done():
+					require.FailNow(t, "timed out waiting for DELETED watch event")
+				}
+			},
+		},
+	}
+
+	storeImpls := []struct {
+		Name string
+		Init func() (storepkg.Store, error)
+	}{
+		{
+			Name: "badger",
+			Init: func() (storepkg.Store, error) {
+				return badger.NewBadgerStore(t.TempDir(), true, logger.Sugar())
+			},
+		},
+	}
+
+	for _, testCase := range testCases {
+		for _, storeImpl := range storeImpls {
+			name := fmt.Sprintf("%s-%s", testCase.Name, storeImpl.Name)
+
+			t.Run(name, func(t *testing.T) {
+				store, err := storeImpl.Init()
+				require.NoError(t, err)
+
+				testCase.Run(t, store)
+			})
+		}
+	}
+}