fix: "... has no deployed releases" error when release history contains only failed releases and history limit reached

Fixed old releases rotation procedure to not require a deployed release to exists.

An error will arise when there are no successfully deployed release yet, but releases history limit has been reached. In such situation helm will refuse to upgrade release anymore with "... has no deployed releases" error.

Furthermore, release rotation procedure already expecting lastDeployedRelease to be either nil, or not nil. So it is assumed that deployed release may exist or may not and these both outcomes were already expected as a valid situation rather than a failure.

Reworked storage_test.go TestStorageRemoveLeastRecentWithError test case: use mocked driver and test release creation procedure does not shadows errors from the underneath release rotation procedure.

Signed-off-by: Timofey Kirillov <timofey.kirillov@flant.com>

pkg/storage/storage.go

@@ -177,7 +177,7 @@ func (s *Storage) removeLeastRecent(name string, max int) error {
 	relutil.SortByRevision(h)
 
 	lastDeployed, err := s.Deployed(name)
-	if err != nil {
+	if err != nil && !errors.Is(err, driver.ErrNoDeployedReleases) {
 		return err
 	}
 

pkg/storage/storage_test.go

@@ -278,8 +278,40 @@ func TestStorageHistory(t *testing.T) {
 	}
 }
 
-func TestStorageRemoveLeastRecentWithError(t *testing.T) {
+var errMaxHistoryMockDriverSomethingHappened = errors.New("something happened")
-	storage := Init(driver.NewMemory())
+
+type MaxHistoryMockDriver struct {
+	Driver driver.Driver
+}
+
+func NewMaxHistoryMockDriver(d driver.Driver) *MaxHistoryMockDriver {
+	return &MaxHistoryMockDriver{Driver: d}
+}
+func (d *MaxHistoryMockDriver) Create(key string, rls *rspb.Release) error {
+	return d.Driver.Create(key, rls)
+}
+func (d *MaxHistoryMockDriver) Update(key string, rls *rspb.Release) error {
+	return d.Driver.Update(key, rls)
+}
+func (d *MaxHistoryMockDriver) Delete(key string) (*rspb.Release, error) {
+	return nil, errMaxHistoryMockDriverSomethingHappened
+}
+func (d *MaxHistoryMockDriver) Get(key string) (*rspb.Release, error) {
+	return d.Driver.Get(key)
+}
+func (d *MaxHistoryMockDriver) List(filter func(*rspb.Release) bool) ([]*rspb.Release, error) {
+	return d.Driver.List(filter)
+}
+func (d *MaxHistoryMockDriver) Query(labels map[string]string) ([]*rspb.Release, error) {
+	return d.Driver.Query(labels)
+}
+func (d *MaxHistoryMockDriver) Name() string {
+	return d.Driver.Name()
+}
+
+func TestMaxHistoryErrorHandling(t *testing.T) {
+	//func TestStorageRemoveLeastRecentWithError(t *testing.T) {
+	storage := Init(NewMaxHistoryMockDriver(driver.NewMemory()))
 	storage.Log = t.Logf
 
 	storage.MaxHistory = 1
@@ -297,7 +329,7 @@ func TestStorageRemoveLeastRecentWithError(t *testing.T) {
 	setup()
 
 	rls2 := ReleaseTestData{Name: name, Version: 2, Status: rspb.StatusSuperseded}.ToRelease()
-	wantErr := driver.ErrNoDeployedReleases
+	wantErr := errMaxHistoryMockDriverSomethingHappened
 	gotErr := storage.Create(rls2)
 	if !errors.Is(gotErr, wantErr) {
 		t.Fatalf("Storing release 'angry-bird' (v2) should return the error %#v, but returned %#v", wantErr, gotErr)
@@ -444,6 +476,65 @@ func TestStorageLast(t *testing.T) {
 	}
 }
 
+// TestUpgradeInitiallyFailedRelease tests a case when there are no deployed release yet, but history limit has been
+// reached: the has-no-deployed-releases error should not occur in such case.
+func TestUpgradeInitiallyFailedReleaseWithHistoryLimit(t *testing.T) {
+	storage := Init(driver.NewMemory())
+	storage.MaxHistory = 4
+
+	const name = "angry-bird"
+
+	// setup storage with test releases
+	setup := func() {
+		// release records
+		rls0 := ReleaseTestData{Name: name, Version: 1, Status: rspb.StatusFailed}.ToRelease()
+		rls1 := ReleaseTestData{Name: name, Version: 2, Status: rspb.StatusFailed}.ToRelease()
+		rls2 := ReleaseTestData{Name: name, Version: 3, Status: rspb.StatusFailed}.ToRelease()
+		rls3 := ReleaseTestData{Name: name, Version: 4, Status: rspb.StatusFailed}.ToRelease()
+
+		// create the release records in the storage
+		assertErrNil(t.Fatal, storage.Create(rls0), "Storing release 'angry-bird' (v1)")
+		assertErrNil(t.Fatal, storage.Create(rls1), "Storing release 'angry-bird' (v2)")
+		assertErrNil(t.Fatal, storage.Create(rls2), "Storing release 'angry-bird' (v3)")
+		assertErrNil(t.Fatal, storage.Create(rls3), "Storing release 'angry-bird' (v4)")
+
+		hist, err := storage.History(name)
+		if err != nil {
+			t.Fatalf("unexpected error: %s", err)
+		}
+
+		wantHistoryLen := 4
+		if len(hist) != wantHistoryLen {
+			t.Fatalf("expected history of release %q to contain %d releases, got %d", name, wantHistoryLen, len(hist))
+		}
+	}
+
+	setup()
+
+	rls5 := ReleaseTestData{Name: name, Version: 5, Status: rspb.StatusFailed}.ToRelease()
+	err := storage.Create(rls5)
+	if err != nil {
+		t.Fatalf("Failed to create a new release version: %s", err)
+	}
+
+	hist, err := storage.History(name)
+	if err != nil {
+		t.Fatalf("unexpected error: %s", err)
+	}
+
+	for i, rel := range hist {
+		wantVersion := i + 2
+		if rel.Version != wantVersion {
+			t.Fatalf("Expected history release %d version to equal %d, got %d", i+1, wantVersion, rel.Version)
+		}
+
+		wantStatus := rspb.StatusFailed
+		if rel.Info.Status != wantStatus {
+			t.Fatalf("Expected history release %d status to equal %q, got %q", i+1, wantStatus, rel.Info.Status)
+		}
+	}
+}
+
 type ReleaseTestData struct {
 	Name      string
 	Version   int