WIP: pkg/upgrade: abstract resource deletion with Action

pkg/action/action.go

@@ -0,0 +1,307 @@
+package action
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"strings"
+	"time"
+
+	"github.com/hashicorp/go-multierror"
+	"k8s.io/apimachinery/pkg/api/meta"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/util/wait"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+)
+
+type ResourceSpec struct {
+	Gvk       schema.GroupVersionKind
+	Namespace string
+	// path to the field, like "metadata", "name"
+	Path []string
+	// set of values for the field to match object, any one matches
+	Values []string
+}
+
+type MatcherFunc func(r ResourceSpec, obj *unstructured.Unstructured) (bool, error)
+type Func func(ctx context.Context, c client.Client, r ResourceSpec, obj *unstructured.Unstructured) error
+type RetryCheckFunc func(ctx context.Context, c client.Client, resources ...ResourceSpec) (bool, error)
+
+type Action struct {
+	client client.Client
+
+	matcher MatcherFunc
+	actions []Func
+}
+
+// shouldn't just return false on error?
+func DefaultMatcher(r ResourceSpec, obj *unstructured.Unstructured) (bool, error) {
+	if len(r.Path) == 0 || len(r.Values) == 0 {
+		return true, nil
+	}
+
+	v, ok, err := unstructured.NestedString(obj.Object, r.Path...)
+	if err != nil {
+		return false, fmt.Errorf("failed to get field %v for %s %s/%s: %w", r.Path, r.Gvk.Kind, r.Namespace, obj.GetName(), err)
+	}
+
+	if !ok {
+		return false, fmt.Errorf("unexisting path to handle: %v", r.Path)
+	}
+
+	for _, toDelete := range r.Values {
+		if v == toDelete {
+			return true, nil
+		}
+	}
+
+	return false, nil
+}
+
+func New(c client.Client) *Action {
+	return &Action{
+		client:  c,
+		matcher: DefaultMatcher,
+	}
+}
+
+func Not(m MatcherFunc) MatcherFunc {
+	return func(r ResourceSpec, obj *unstructured.Unstructured) (bool, error) {
+		matched, err := m(r, obj)
+		return !matched, err
+	}
+}
+
+func Any(matchers ...MatcherFunc) MatcherFunc {
+	return func(r ResourceSpec, obj *unstructured.Unstructured) (bool, error) {
+		for _, m := range matchers {
+			matched, err := m(r, obj)
+			if err != nil {
+				return false, err
+			}
+			if matched {
+				return true, err
+			}
+		}
+		return false, nil
+	}
+}
+
+func All(matchers ...MatcherFunc) MatcherFunc {
+	return func(r ResourceSpec, obj *unstructured.Unstructured) (bool, error) {
+		for _, m := range matchers {
+			matched, err := m(r, obj)
+			if err != nil {
+				return false, err
+			}
+			if !matched {
+				return false, err
+			}
+		}
+		return true, nil
+	}
+}
+
+func (o *Action) ForMatched(m MatcherFunc) *Action {
+	o.matcher = m
+	return o
+}
+
+func (o *Action) Do(a Func) *Action {
+	o.actions = append(o.actions, a)
+	return o
+}
+
+func (o *Action) execOneResource(ctx context.Context, r ResourceSpec, objs []*unstructured.Unstructured) error {
+	for _, item := range objs {
+		for _, a := range o.actions {
+			err := a(ctx, o.client, r, item)
+			if err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}
+
+func ListMatched(ctx context.Context, c client.Client, matcher MatcherFunc, resources ...ResourceSpec) (map[*ResourceSpec][]*unstructured.Unstructured, error) {
+	ret := make(map[*ResourceSpec][]*unstructured.Unstructured)
+
+	for _, r := range resources {
+		r := r
+		var items []*unstructured.Unstructured
+
+		list := &unstructured.UnstructuredList{}
+		list.SetGroupVersionKind(r.Gvk)
+
+		err := c.List(ctx, list, client.InNamespace(r.Namespace))
+		if err != nil {
+			if errors.Is(err, &meta.NoKindMatchError{}) {
+				fmt.Printf("Could not list %v: CRD not found\n", r.Gvk)
+				continue
+			}
+			return ret, fmt.Errorf("failed to list %s: %w", r.Gvk.Kind, err)
+		}
+
+		for _, item := range list.Items {
+			item := item
+
+			matched, err := matcher(r, &item)
+			if err != nil {
+				return ret, err
+			}
+
+			if !matched {
+				continue
+			}
+
+			items = append(items, &item)
+		}
+
+		if len(items) > 0 {
+			ret[&r] = items
+		}
+	}
+
+	return ret, nil
+}
+
+func (o *Action) Exec(ctx context.Context, resources ...ResourceSpec) error {
+	var errors *multierror.Error
+
+	matched, err := ListMatched(ctx, o.client, o.matcher, resources...)
+	if err != nil {
+		return err
+	}
+
+	for r, objs := range matched {
+		err := o.execOneResource(ctx, *r, objs)
+		errors = multierror.Append(errors, err)
+	}
+
+	return errors.ErrorOrNil()
+}
+
+func (o *Action) ExecWithRetry(ctx context.Context, shouldRetry RetryCheckFunc, resources ...ResourceSpec) error {
+	return wait.ExponentialBackoffWithContext(ctx, wait.Backoff{
+		// 5, 10, ,20, 40 then timeout
+		Duration: 5 * time.Second,
+		Factor:   2.0,
+		Jitter:   0.1,
+		Steps:    4,
+		Cap:      1 * time.Minute,
+	}, func(ctx context.Context) (bool, error) {
+		err := o.Exec(ctx, resources...)
+		if err != nil {
+			return false, err
+		}
+		return shouldRetry(ctx, o.client, resources...)
+	})
+}
+
+func (o *Action) DryRun(_ context.Context, _ ...ResourceSpec) error {
+	return nil
+}
+
+func Delete(ctx context.Context, c client.Client, _ ResourceSpec, obj *unstructured.Unstructured) error {
+	return client.IgnoreNotFound(c.Delete(ctx, obj))
+}
+
+func IfAnyLeft(matcher MatcherFunc) RetryCheckFunc {
+	return func(ctx context.Context, c client.Client, resources ...ResourceSpec) (bool, error) {
+		matched, err := ListMatched(ctx, c, matcher, resources...)
+		if err != nil {
+			return false, err
+		}
+
+		return len(matched) == 0, nil
+	}
+}
+
+func deleteField(obj map[string]any, path ...string) error {
+	if len(path) < 1 {
+		return fmt.Errorf("path is empty")
+	}
+
+	parent := path[:len(path)-1]
+	field := path[len(path)-1]
+
+	v, ok, err := unstructured.NestedFieldNoCopy(obj, parent...)
+	if err != nil || !ok {
+		return fmt.Errorf("Not found or error")
+	}
+
+	m, ok := v.(map[string]any)
+	if !ok {
+		return fmt.Errorf("field is not map")
+	}
+	delete(m, field)
+	return nil
+}
+
+func DeleteField(path ...string) Func {
+	return func(ctx context.Context, c client.Client, r ResourceSpec, obj *unstructured.Unstructured) error {
+		err := deleteField(obj.Object, path...)
+		if err != nil {
+			return fmt.Errorf("could not delete field %v in object %s : %w", path, obj.GetName(), err)
+		}
+
+		err = c.Update(ctx, obj)
+		if err != nil {
+			return fmt.Errorf("error updating object while removing %v from %v : %w", path, obj.GetName(), err)
+		}
+
+		return nil
+	}
+}
+
+func MatchMap(key, value string, keyMatch func(value, pattern string) bool, path ...string) MatcherFunc {
+	return func(r ResourceSpec, obj *unstructured.Unstructured) (bool, error) {
+		m, ok, err := unstructured.NestedStringMap(obj.Object, path...)
+		if err != nil || !ok {
+			return false, err
+		}
+
+		for k, v := range m {
+			if !keyMatch(k, key) {
+				continue
+			}
+
+			if value == "" || v == value {
+				return true, nil
+			}
+		}
+
+		return false, nil
+	}
+}
+
+func MatchMapKeyContains(key string, path ...string) MatcherFunc {
+	return MatchMap(key, "", strings.Contains, path...)
+}
+
+func NewDelete(c client.Client) *Action {
+	return New(c).Do(Delete)
+}
+
+func NewDeleteMatched(c client.Client, m MatcherFunc) *Action {
+	return New(c).Do(Delete).ForMatched(m)
+}
+
+func NewDeleteWithFinalizer(c client.Client) *Action {
+	return New(c).
+		Do(DeleteField("metadata", "finalizer")).
+		Do(Delete)
+}
+
+func NewDeleteOwnersReferences(c client.Client) *Action {
+	return New(c).
+		Do(DeleteField("metadata", "ownerReferences"))
+}
+
+func NewDeleteLabel(c client.Client, label string) *Action {
+	return New(c).
+		Do(DeleteField("metadata", "labels", label))
+}