API definition for model store (#249)

Basic API definitions for model store CRUD operations

src/internal/kopia/model_store.go

@@ -0,0 +1,67 @@
+package kopia
+
+import (
+	"context"
+)
+
+// ID of the manifest in kopia. This is not guaranteed to be stable.
+type ID string
+type modelType int
+
+//go:generate stringer -type=modelType
+const (
+	UnknownModel = modelType(iota)
+	BackupOpModel
+	RestoreOpModel
+	RestorePointModel
+
+	errStoreFlush = "flushing manifest store"
+)
+
+type ModelStore struct{}
+
+// Put adds a model of the given type to the persistent model store. Any tags
+// given to this function can later be used to help lookup the model. The
+// returned ID can be used for subsequent Get, Update, or Delete calls.
+func (ms *ModelStore) Put(
+	ctx context.Context,
+	t modelType,
+	tags map[string]string,
+	m any,
+) (ID, error) {
+	return "", nil
+}
+
+// GetIDsForType returns all IDs for models that match the given type and have
+// the given tags. Returned IDs can be used in subsequent calls to Get, Update,
+// or Delete.
+func (ms *ModelStore) GetIDsForType(
+	ctx context.Context,
+	t modelType,
+	tags map[string]string,
+) ([]ID, error) {
+	return nil, nil
+}
+
+// Get deserializes the model with the given ID into data.
+func (ms *ModelStore) Get(ctx context.Context, id ID, data any) error {
+	return nil
+}
+
+// Update adds the new version of the model to the model store and deletes the
+// version of the model with oldID if the old and new IDs do not match. The new
+// ID of the model is returned.
+func (ms *ModelStore) Update(
+	ctx context.Context,
+	t modelType,
+	oldID ID,
+	tags map[string]string,
+	m any,
+) (ID, error) {
+	return "", nil
+}
+
+// Delete deletes the model with the given ID from the model store.
+func (ms *ModelStore) Delete(ctx context.Context, id ID) error {
+	return nil
+}

src/internal/kopia/modeltype_string.go

@@ -0,0 +1,26 @@
+// Code generated by "stringer -type=modelType"; DO NOT EDIT.
+
+package kopia
+
+import "strconv"
+
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[UnknownModel-0]
+	_ = x[BackupOpModel-1]
+	_ = x[RestoreOpModel-2]
+	_ = x[RestorePointModel-3]
+}
+
+const _modelType_name = "UnknownModelBackupOpModelRestoreOpModelRestorePointModel"
+
+var _modelType_index = [...]uint8{0, 12, 25, 39, 56}
+
+func (i modelType) String() string {
+	if i < 0 || i >= modelType(len(_modelType_index)-1) {
+		return "modelType(" + strconv.FormatInt(int64(i), 10) + ")"
+	}
+	return _modelType_name[_modelType_index[i]:_modelType_index[i+1]]
+}