kubernetes/pkg/kubelet/kubeletconfig/configfiles/configfiles.go
obitech bba15d358c Add strict deserialization for kubelet component config
CodecFactory is started with EnableStrict that throws an error when deserializing
a Kubelet component config that is malformed (e.g. unknown or duplicate keys).

When strict decoding a v1beta1 config fails, non-strict decoding is used and a warning is emitted.
For this, NewSchemeAndCodecs is now a variadic function that can take multiple
arguments for augmenting the returned codec factory. Strict decoding is
then explicitely enabled when decoding a kubelet config.
Additionally, decoding a RemoteConfigSource needs to be non-strict
to avoid an accidental error when it contains newer API fields that are not
yet known to the Kubelet.

DecodeKubeletConfiguration returns a wrapped error instead of a simple string
so its type can be tested.

Add unit tests for unhappy paths when loading a component config

Add keys for test cases struct fields, remove nil field initialization

Co-Authored-By: Jordan Liggitt <jordan@liggitt.net>
2019-10-24 19:37:35 +02:00

91 lines
3.0 KiB
Go

/*
Copyright 2017 The Kubernetes Authors.
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 configfiles
import (
"fmt"
"path/filepath"
"k8s.io/apimachinery/pkg/runtime/serializer"
kubeletconfig "k8s.io/kubernetes/pkg/kubelet/apis/config"
kubeletscheme "k8s.io/kubernetes/pkg/kubelet/apis/config/scheme"
utilcodec "k8s.io/kubernetes/pkg/kubelet/kubeletconfig/util/codec"
utilfs "k8s.io/kubernetes/pkg/util/filesystem"
)
// Loader loads configuration from a storage layer
type Loader interface {
// Load loads and returns the KubeletConfiguration from the storage layer, or an error if a configuration could not be loaded
Load() (*kubeletconfig.KubeletConfiguration, error)
}
// fsLoader loads configuration from `configDir`
type fsLoader struct {
// fs is the filesystem where the config files exist; can be mocked for testing
fs utilfs.Filesystem
// kubeletCodecs is the scheme used to decode config files
kubeletCodecs *serializer.CodecFactory
// kubeletFile is an absolute path to the file containing a serialized KubeletConfiguration
kubeletFile string
}
// NewFsLoader returns a Loader that loads a KubeletConfiguration from the `kubeletFile`
func NewFsLoader(fs utilfs.Filesystem, kubeletFile string) (Loader, error) {
_, kubeletCodecs, err := kubeletscheme.NewSchemeAndCodecs(serializer.EnableStrict)
if err != nil {
return nil, err
}
return &fsLoader{
fs: fs,
kubeletCodecs: kubeletCodecs,
kubeletFile: kubeletFile,
}, nil
}
func (loader *fsLoader) Load() (*kubeletconfig.KubeletConfiguration, error) {
data, err := loader.fs.ReadFile(loader.kubeletFile)
if err != nil {
return nil, fmt.Errorf("failed to read kubelet config file %q, error: %v", loader.kubeletFile, err)
}
// no configuration is an error, some parameters are required
if len(data) == 0 {
return nil, fmt.Errorf("kubelet config file %q was empty", loader.kubeletFile)
}
kc, err := utilcodec.DecodeKubeletConfiguration(loader.kubeletCodecs, data)
if err != nil {
return nil, err
}
// make all paths absolute
resolveRelativePaths(kubeletconfig.KubeletConfigurationPathRefs(kc), filepath.Dir(loader.kubeletFile))
return kc, nil
}
// resolveRelativePaths makes relative paths absolute by resolving them against `root`
func resolveRelativePaths(paths []*string, root string) {
for _, path := range paths {
// leave empty paths alone, "no path" is a valid input
// do not attempt to resolve paths that are already absolute
if len(*path) > 0 && !filepath.IsAbs(*path) {
*path = filepath.Join(root, *path)
}
}
}