Files
kubectx/internal/kubeconfig/contexts.go
Ahmet Alp Balkan 0d800e1367 fix: improve error handling and resource management in kubeconfig (#476)
This change addresses eight key improvements to the kubectx/kubens codebase:

Resource Management Fixes:
- Fix use-after-close bugs where Kubeconfig was accessed after Close()
- Fix resource leaks on error paths by ensuring defer kc.Close() is called
- Fix YAML encoder not being closed after Encode(), causing buffered data loss

API Design Improvements:
- Change ContextNames() to return ([]string, error) instead of silently returning
  nil on error, making parse failures distinguishable from empty results
- Change GetCurrentContext() to return (string, error) instead of returning ""
  for both "not set" and parse error cases
- Update all 16 call sites across cmd/kubectx and cmd/kubens packages to handle
  the new error returns while preserving backward-compatible behavior

Error Handling:
- Add explicit error handling for printer.Success() calls in 5+ locations
  by prefixing unchecked calls with _ =

Performance:
- Add slice pre-allocation in namespace list pagination using slices.Grow()
  before append loops, reducing allocations when fetching 500+ item batches

All changes maintain backward compatibility for missing kubeconfig keys while
improving error transparency and resource safety.
2026-03-08 17:44:18 -07:00

75 lines
1.9 KiB
Go

// Copyright 2021 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package kubeconfig
import (
"errors"
"fmt"
"slices"
"sigs.k8s.io/kustomize/kyaml/yaml"
)
func (k *Kubeconfig) contextsNode() (*yaml.RNode, error) {
contexts, err := k.config.Pipe(yaml.Get("contexts"))
if err != nil {
return nil, err
}
if contexts == nil {
return nil, errors.New("\"contexts\" entry is nil")
} else if contexts.YNode().Kind != yaml.SequenceNode {
return nil, errors.New("\"contexts\" is not a sequence node")
}
return contexts, nil
}
func (k *Kubeconfig) contextNode(name string) (*yaml.RNode, error) {
contexts, err := k.contextsNode()
if err != nil {
return nil, err
}
context, err := contexts.Pipe(yaml.Lookup("[name=" + name + "]"))
if err != nil {
return nil, err
}
if context == nil {
return nil, fmt.Errorf("context with name \"%s\" not found", name)
}
return context, nil
}
func (k *Kubeconfig) ContextNames() ([]string, error) {
contexts, err := k.config.Pipe(yaml.Get("contexts"))
if err != nil {
return nil, fmt.Errorf("failed to get contexts: %w", err)
}
if contexts == nil {
return nil, nil
}
names, err := contexts.ElementValues("name")
if err != nil {
return nil, fmt.Errorf("failed to get context names: %w", err)
}
return names, nil
}
func (k *Kubeconfig) ContextExists(name string) (bool, error) {
names, err := k.ContextNames()
if err != nil {
return false, err
}
return slices.Contains(names, name), nil
}