kubernetes store 源码
kubernetes store 代码
文件路径：/staging/src/k8s.io/apiserver/pkg/storage/etcd3/store.go
/*
Copyright 2016 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 etcd3
import (
"bytes"
"context"
"errors"
"fmt"
"path"
"reflect"
"strings"
"time"
clientv3 "go.etcd.io/etcd/client/v3"
apierrors "k8s.io/apimachinery/pkg/api/errors"
"k8s.io/apimachinery/pkg/api/meta"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/runtime/schema"
"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
"k8s.io/apimachinery/pkg/conversion"
"k8s.io/apimachinery/pkg/runtime"
"k8s.io/apimachinery/pkg/watch"
endpointsrequest "k8s.io/apiserver/pkg/endpoints/request"
"k8s.io/apiserver/pkg/features"
"k8s.io/apiserver/pkg/storage"
"k8s.io/apiserver/pkg/storage/etcd3/metrics"
"k8s.io/apiserver/pkg/storage/value"
utilfeature "k8s.io/apiserver/pkg/util/feature"
"k8s.io/klog/v2"
utiltrace "k8s.io/utils/trace"
)
const (
// maxLimit is a maximum page limit increase used when fetching objects from etcd.
// This limit is used only for increasing page size by kube-apiserver. If request
// specifies larger limit initially, it won't be changed.
maxLimit = 10000
)
// authenticatedDataString satisfies the value.Context interface. It uses the key to
// authenticate the stored data. This does not defend against reuse of previously
// encrypted values under the same key, but will prevent an attacker from using an
// encrypted value from a different key. A stronger authenticated data segment would
// include the etcd3 Version field (which is incremented on each write to a key and
// reset when the key is deleted), but an attacker with write access to etcd can
// force deletion and recreation of keys to weaken that angle.
type authenticatedDataString string
// AuthenticatedData implements the value.Context interface.
func (d authenticatedDataString) AuthenticatedData() []byte {
return []byte(string(d))
}
var _ value.Context = authenticatedDataString("")
type store struct {
client *clientv3.Client
codec runtime.Codec
versioner storage.Versioner
transformer value.Transformer
pathPrefix string
groupResource schema.GroupResource
groupResourceString string
watcher *watcher
pagingEnabled bool
leaseManager *leaseManager
}
type objState struct {
obj runtime.Object
meta *storage.ResponseMeta
rev int64
data []byte
stale bool
}
// New returns an etcd3 implementation of storage.Interface.
func New(c *clientv3.Client, codec runtime.Codec, newFunc func() runtime.Object, prefix string, groupResource schema.GroupResource, transformer value.Transformer, pagingEnabled bool, leaseManagerConfig LeaseManagerConfig) storage.Interface {
return newStore(c, codec, newFunc, prefix, groupResource, transformer, pagingEnabled, leaseManagerConfig)
}
func newStore(c *clientv3.Client, codec runtime.Codec, newFunc func() runtime.Object, prefix string, groupResource schema.GroupResource, transformer value.Transformer, pagingEnabled bool, leaseManagerConfig LeaseManagerConfig) *store {
versioner := storage.APIObjectVersioner{}
result := &store{
client: c,
codec: codec,
versioner: versioner,
transformer: transformer,
pagingEnabled: pagingEnabled,
// for compatibility with etcd2 impl.
// no-op for default prefix of '/registry'.
// keeps compatibility with etcd2 impl for custom prefixes that don't start with '/'
pathPrefix: path.Join("/", prefix),
groupResource: groupResource,
groupResourceString: groupResource.String(),
watcher: newWatcher(c, codec, groupResource, newFunc, versioner, transformer),
leaseManager: newDefaultLeaseManager(c, leaseManagerConfig),
}
return result
}
// Versioner implements storage.Interface.Versioner.
func (s *store) Versioner() storage.Versioner {
return s.versioner
}
// Get implements storage.Interface.Get.
func (s *store) Get(ctx context.Context, key string, opts storage.GetOptions, out runtime.Object) error {
key = path.Join(s.pathPrefix, key)
startTime := time.Now()
getResp, err := s.client.KV.Get(ctx, key)
metrics.RecordEtcdRequestLatency("get", s.groupResourceString, startTime)
if err != nil {
return err
}
if err = s.validateMinimumResourceVersion(opts.ResourceVersion, uint64(getResp.Header.Revision)); err != nil {
return err
}
if len(getResp.Kvs) == 0 {
if opts.IgnoreNotFound {
return runtime.SetZeroValue(out)
}
return storage.NewKeyNotFoundError(key, 0)
}
kv := getResp.Kvs[0]
data, _, err := s.transformer.TransformFromStorage(ctx, kv.Value, authenticatedDataString(key))
if err != nil {
return storage.NewInternalError(err.Error())
}
return decode(s.codec, s.versioner, data, out, kv.ModRevision)
}
// Create implements storage.Interface.Create.
func (s *store) Create(ctx context.Context, key string, obj, out runtime.Object, ttl uint64) error {
trace := utiltrace.New("Create etcd3",
utiltrace.Field{Key: "audit-id", Value: endpointsrequest.GetAuditIDTruncated(ctx)},
utiltrace.Field{Key: "key", Value: key},
utiltrace.Field{Key: "type", Value: getTypeName(obj)},
utiltrace.Field{Key: "resource", Value: s.groupResourceString},
)
defer trace.LogIfLong(500 * time.Millisecond)
if version, err := s.versioner.ObjectResourceVersion(obj); err == nil && version != 0 {
return errors.New("resourceVersion should not be set on objects to be created")
}
if err := s.versioner.PrepareObjectForStorage(obj); err != nil {
return fmt.Errorf("PrepareObjectForStorage failed: %v", err)
}
trace.Step("About to Encode")
data, err := runtime.Encode(s.codec, obj)
trace.Step("Encode finished", utiltrace.Field{Key: "len", Value: len(data)}, utiltrace.Field{Key: "err", Value: err})
if err != nil {
return err
}
key = path.Join(s.pathPrefix, key)
opts, err := s.ttlOpts(ctx, int64(ttl))
if err != nil {
return err
}
newData, err := s.transformer.TransformToStorage(ctx, data, authenticatedDataString(key))
trace.Step("TransformToStorage finished", utiltrace.Field{Key: "err", Value: err})
if err != nil {
return storage.NewInternalError(err.Error())
}
startTime := time.Now()
txnResp, err := s.client.KV.Txn(ctx).If(
notFound(key),
).Then(
clientv3.OpPut(key, string(newData), opts...),
).Commit()
metrics.RecordEtcdRequestLatency("create", s.groupResourceString, startTime)
trace.Step("Txn call finished", utiltrace.Field{Key: "err", Value: err})
if err != nil {
return err
}
if !txnResp.Succeeded {
return storage.NewKeyExistsError(key, 0)
}
if out != nil {
putResp := txnResp.Responses[0].GetResponsePut()
err = decode(s.codec, s.versioner, data, out, putResp.Header.Revision)
trace.Step("decode finished", utiltrace.Field{Key: "len", Value: len(data)}, utiltrace.Field{Key: "err", Value: err})
return err
}
return nil
}
// Delete implements storage.Interface.Delete.
func (s *store) Delete(
ctx context.Context, key string, out runtime.Object, preconditions *storage.Preconditions,
validateDeletion storage.ValidateObjectFunc, cachedExistingObject runtime.Object) error {
v, err := conversion.EnforcePtr(out)
if err != nil {
return fmt.Errorf("unable to convert output object to pointer: %v", err)
}
key = path.Join(s.pathPrefix, key)
return s.conditionalDelete(ctx, key, out, v, preconditions, validateDeletion, cachedExistingObject)
}
func (s *store) conditionalDelete(
ctx context.Context, key string, out runtime.Object, v reflect.Value, preconditions *storage.Preconditions,
validateDeletion storage.ValidateObjectFunc, cachedExistingObject runtime.Object) error {
getCurrentState := func() (*objState, error) {
startTime := time.Now()
getResp, err := s.client.KV.Get(ctx, key)
metrics.RecordEtcdRequestLatency("get", s.groupResourceString, startTime)
if err != nil {
return nil, err
}
return s.getState(ctx, getResp, key, v, false)
}
var origState *objState
var err error
var origStateIsCurrent bool
if cachedExistingObject != nil {
origState, err = s.getStateFromObject(cachedExistingObject)
} else {
origState, err = getCurrentState()
origStateIsCurrent = true
}
if err != nil {
return err
}
for {
if preconditions != nil {
if err := preconditions.Check(key, origState.obj); err != nil {
if origStateIsCurrent {
return err
}
// It's possible we're working with stale data.
// Remember the revision of the potentially stale data and the resulting update error
cachedRev := origState.rev
cachedUpdateErr := err
// Actually fetch
origState, err = getCurrentState()
if err != nil {
return err
}
origStateIsCurrent = true
// it turns out our cached data was not stale, return the error
if cachedRev == origState.rev {
return cachedUpdateErr
}
// Retry
continue
}
}
if err := validateDeletion(ctx, origState.obj); err != nil {
if origStateIsCurrent {
return err
}
// It's possible we're working with stale data.
// Remember the revision of the potentially stale data and the resulting update error
cachedRev := origState.rev
cachedUpdateErr := err
// Actually fetch
origState, err = getCurrentState()
if err != nil {
return err
}
origStateIsCurrent = true
// it turns out our cached data was not stale, return the error
if cachedRev == origState.rev {
return cachedUpdateErr
}
// Retry
continue
}
startTime := time.Now()
txnResp, err := s.client.KV.Txn(ctx).If(
clientv3.Compare(clientv3.ModRevision(key), "=", origState.rev),
).Then(
clientv3.OpDelete(key),
).Else(
clientv3.OpGet(key),
).Commit()
metrics.RecordEtcdRequestLatency("delete", s.groupResourceString, startTime)
if err != nil {
return err
}
if !txnResp.Succeeded {
getResp := (*clientv3.GetResponse)(txnResp.Responses[0].GetResponseRange())
klog.V(4).Infof("deletion of %s failed because of a conflict, going to retry", key)
origState, err = s.getState(ctx, getResp, key, v, false)
if err != nil {
return err
}
origStateIsCurrent = true
continue
}
return decode(s.codec, s.versioner, origState.data, out, origState.rev)
}
}
// GuaranteedUpdate implements storage.Interface.GuaranteedUpdate.
func (s *store) GuaranteedUpdate(
ctx context.Context, key string, destination runtime.Object, ignoreNotFound bool,
preconditions *storage.Preconditions, tryUpdate storage.UpdateFunc, cachedExistingObject runtime.Object) error {
trace := utiltrace.New("GuaranteedUpdate etcd3",
utiltrace.Field{Key: "audit-id", Value: endpointsrequest.GetAuditIDTruncated(ctx)},
utiltrace.Field{Key: "key", Value: key},
utiltrace.Field{Key: "type", Value: getTypeName(destination)},
utiltrace.Field{Key: "resource", Value: s.groupResourceString})
defer trace.LogIfLong(500 * time.Millisecond)
v, err := conversion.EnforcePtr(destination)
if err != nil {
return fmt.Errorf("unable to convert output object to pointer: %v", err)
}
key = path.Join(s.pathPrefix, key)
getCurrentState := func() (*objState, error) {
startTime := time.Now()
getResp, err := s.client.KV.Get(ctx, key)
metrics.RecordEtcdRequestLatency("get", s.groupResourceString, startTime)
if err != nil {
return nil, err
}
return s.getState(ctx, getResp, key, v, ignoreNotFound)
}
var origState *objState
var origStateIsCurrent bool
if cachedExistingObject != nil {
origState, err = s.getStateFromObject(cachedExistingObject)
} else {
origState, err = getCurrentState()
origStateIsCurrent = true
}
if err != nil {
return err
}
trace.Step("initial value restored")
transformContext := authenticatedDataString(key)
for {
if err := preconditions.Check(key, origState.obj); err != nil {
// If our data is already up to date, return the error
if origStateIsCurrent {
return err
}
// It's possible we were working with stale data
// Actually fetch
origState, err = getCurrentState()
if err != nil {
return err
}
origStateIsCurrent = true
// Retry
continue
}
ret, ttl, err := s.updateState(origState, tryUpdate)
if err != nil {
// If our data is already up to date, return the error
if origStateIsCurrent {
return err
}
// It's possible we were working with stale data
// Remember the revision of the potentially stale data and the resulting update error
cachedRev := origState.rev
cachedUpdateErr := err
// Actually fetch
origState, err = getCurrentState()
if err != nil {
return err
}
origStateIsCurrent = true
// it turns out our cached data was not stale, return the error
if cachedRev == origState.rev {
return cachedUpdateErr
}
// Retry
continue
}
trace.Step("About to Encode")
data, err := runtime.Encode(s.codec, ret)
trace.Step("Encode finished", utiltrace.Field{Key: "len", Value: len(data)}, utiltrace.Field{Key: "err", Value: err})
if err != nil {
return err
}
if !origState.stale && bytes.Equal(data, origState.data) {
// if we skipped the original Get in this loop, we must refresh from
// etcd in order to be sure the data in the store is equivalent to
// our desired serialization
if !origStateIsCurrent {
origState, err = getCurrentState()
if err != nil {
return err
}
origStateIsCurrent = true
if !bytes.Equal(data, origState.data) {
// original data changed, restart loop
continue
}
}
// recheck that the data from etcd is not stale before short-circuiting a write
if !origState.stale {
return decode(s.codec, s.versioner, origState.data, destination, origState.rev)
}
}
newData, err := s.transformer.TransformToStorage(ctx, data, transformContext)
trace.Step("TransformToStorage finished", utiltrace.Field{Key: "err", Value: err})
if err != nil {
return storage.NewInternalError(err.Error())
}
opts, err := s.ttlOpts(ctx, int64(ttl))
if err != nil {
return err
}
trace.Step("Transaction prepared")
startTime := time.Now()
txnResp, err := s.client.KV.Txn(ctx).If(
clientv3.Compare(clientv3.ModRevision(key), "=", origState.rev),
).Then(
clientv3.OpPut(key, string(newData), opts...),
).Else(
clientv3.OpGet(key),
).Commit()
metrics.RecordEtcdRequestLatency("update", s.groupResourceString, startTime)
trace.Step("Txn call finished", utiltrace.Field{Key: "err", Value: err})
if err != nil {
return err
}
trace.Step("Transaction committed")
if !txnResp.Succeeded {
getResp := (*clientv3.GetResponse)(txnResp.Responses[0].GetResponseRange())
klog.V(4).Infof("GuaranteedUpdate of %s failed because of a conflict, going to retry", key)
origState, err = s.getState(ctx, getResp, key, v, ignoreNotFound)
if err != nil {
return err
}
trace.Step("Retry value restored")
origStateIsCurrent = true
continue
}
putResp := txnResp.Responses[0].GetResponsePut()
err = decode(s.codec, s.versioner, data, destination, putResp.Header.Revision)
trace.Step("decode finished", utiltrace.Field{Key: "len", Value: len(data)}, utiltrace.Field{Key: "err", Value: err})
return err
}
}
func getNewItemFunc(listObj runtime.Object, v reflect.Value) func() runtime.Object {
// For unstructured lists with a target group/version, preserve the group/version in the instantiated list items
if unstructuredList, isUnstructured := listObj.(*unstructured.UnstructuredList); isUnstructured {
if apiVersion := unstructuredList.GetAPIVersion(); len(apiVersion) > 0 {
return func() runtime.Object {
return &unstructured.Unstructured{Object: map[string]interface{}{"apiVersion": apiVersion}}
}
}
}
// Otherwise just instantiate an empty item
elem := v.Type().Elem()
return func() runtime.Object {
return reflect.New(elem).Interface().(runtime.Object)
}
}
func (s *store) Count(key string) (int64, error) {
key = path.Join(s.pathPrefix, key)
// We need to make sure the key ended with "/" so that we only get children "directories".
// e.g. if we have key "/a", "/a/b", "/ab", getting keys with prefix "/a" will return all three,
// while with prefix "/a/" will return only "/a/b" which is the correct answer.
if !strings.HasSuffix(key, "/") {
key += "/"
}
startTime := time.Now()
getResp, err := s.client.KV.Get(context.Background(), key, clientv3.WithRange(clientv3.GetPrefixRangeEnd(key)), clientv3.WithCountOnly())
metrics.RecordEtcdRequestLatency("listWithCount", key, startTime)
if err != nil {
return 0, err
}
return getResp.Count, nil
}
// GetList implements storage.Interface.
func (s *store) GetList(ctx context.Context, key string, opts storage.ListOptions, listObj runtime.Object) error {
recursive := opts.Recursive
resourceVersion := opts.ResourceVersion
match := opts.ResourceVersionMatch
pred := opts.Predicate
trace := utiltrace.New(fmt.Sprintf("List(recursive=%v) etcd3", recursive),
utiltrace.Field{Key: "audit-id", Value: endpointsrequest.GetAuditIDTruncated(ctx)},
utiltrace.Field{Key: "key", Value: key},
utiltrace.Field{Key: "resourceVersion", Value: resourceVersion},
utiltrace.Field{Key: "resourceVersionMatch", Value: match},
utiltrace.Field{Key: "limit", Value: pred.Limit},
utiltrace.Field{Key: "continue", Value: pred.Continue})
defer trace.LogIfLong(500 * time.Millisecond)
listPtr, err := meta.GetItemsPtr(listObj)
if err != nil {
return err
}
v, err := conversion.EnforcePtr(listPtr)
if err != nil || v.Kind() != reflect.Slice {
return fmt.Errorf("need ptr to slice: %v", err)
}
key = path.Join(s.pathPrefix, key)
// For recursive lists, we need to make sure the key ended with "/" so that we only
// get children "directories". e.g. if we have key "/a", "/a/b", "/ab", getting keys
// with prefix "/a" will return all three, while with prefix "/a/" will return only
// "/a/b" which is the correct answer.
if recursive && !strings.HasSuffix(key, "/") {
key += "/"
}
keyPrefix := key
// set the appropriate clientv3 options to filter the returned data set
var limitOption *clientv3.OpOption
limit := pred.Limit
var paging bool
options := make([]clientv3.OpOption, 0, 4)
if s.pagingEnabled && pred.Limit > 0 {
paging = true
options = append(options, clientv3.WithLimit(limit))
limitOption = &options[len(options)-1]
}
newItemFunc := getNewItemFunc(listObj, v)
var fromRV *uint64
if len(resourceVersion) > 0 {
parsedRV, err := s.versioner.ParseResourceVersion(resourceVersion)
if err != nil {
return apierrors.NewBadRequest(fmt.Sprintf("invalid resource version: %v", err))
}
fromRV = &parsedRV
}
var returnedRV, continueRV, withRev int64
var continueKey string
switch {
case recursive && s.pagingEnabled && len(pred.Continue) > 0:
continueKey, continueRV, err = storage.DecodeContinue(pred.Continue, keyPrefix)
if err != nil {
return apierrors.NewBadRequest(fmt.Sprintf("invalid continue token: %v", err))
}
if len(resourceVersion) > 0 && resourceVersion != "0" {
return apierrors.NewBadRequest("specifying resource version is not allowed when using continue")
}
rangeEnd := clientv3.GetPrefixRangeEnd(keyPrefix)
options = append(options, clientv3.WithRange(rangeEnd))
key = continueKey
// If continueRV > 0, the LIST request needs a specific resource version.
// continueRV==0 is invalid.
// If continueRV < 0, the request is for the latest resource version.
if continueRV > 0 {
withRev = continueRV
returnedRV = continueRV
}
case recursive && s.pagingEnabled && pred.Limit > 0:
if fromRV != nil {
switch match {
case metav1.ResourceVersionMatchNotOlderThan:
// The not older than constraint is checked after we get a response from etcd,
// and returnedRV is then set to the revision we get from the etcd response.
case metav1.ResourceVersionMatchExact:
returnedRV = int64(*fromRV)
withRev = returnedRV
case "": // legacy case
if *fromRV > 0 {
returnedRV = int64(*fromRV)
withRev = returnedRV
}
default:
return fmt.Errorf("unknown ResourceVersionMatch value: %v", match)
}
}
rangeEnd := clientv3.GetPrefixRangeEnd(keyPrefix)
options = append(options, clientv3.WithRange(rangeEnd))
default:
if fromRV != nil {
switch match {
case metav1.ResourceVersionMatchNotOlderThan:
// The not older than constraint is checked after we get a response from etcd,
// and returnedRV is then set to the revision we get from the etcd response.
case metav1.ResourceVersionMatchExact:
returnedRV = int64(*fromRV)
withRev = returnedRV
case "": // legacy case
default:
return fmt.Errorf("unknown ResourceVersionMatch value: %v", match)
}
}
if recursive {
options = append(options, clientv3.WithPrefix())
}
}
if withRev != 0 {
options = append(options, clientv3.WithRev(withRev))
}
// loop until we have filled the requested limit from etcd or there are no more results
var lastKey []byte
var hasMore bool
var getResp *clientv3.GetResponse
var numFetched int
var numEvald int
// Because these metrics are for understanding the costs of handling LIST requests,
// get them recorded even in error cases.
defer func() {
numReturn := v.Len()
metrics.RecordStorageListMetrics(s.groupResourceString, numFetched, numEvald, numReturn)
}()
for {
startTime := time.Now()
getResp, err = s.client.KV.Get(ctx, key, options...)
if recursive {
metrics.RecordEtcdRequestLatency("list", s.groupResourceString, startTime)
} else {
metrics.RecordEtcdRequestLatency("get", s.groupResourceString, startTime)
}
if err != nil {
return interpretListError(err, len(pred.Continue) > 0, continueKey, keyPrefix)
}
numFetched += len(getResp.Kvs)
if err = s.validateMinimumResourceVersion(resourceVersion, uint64(getResp.Header.Revision)); err != nil {
return err
}
hasMore = getResp.More
if len(getResp.Kvs) == 0 && getResp.More {
return fmt.Errorf("no results were found, but etcd indicated there were more values remaining")
}
// avoid small allocations for the result slice, since this can be called in many
// different contexts and we don't know how significantly the result will be filtered
if pred.Empty() {
growSlice(v, len(getResp.Kvs))
} else {
growSlice(v, 2048, len(getResp.Kvs))
}
// take items from the response until the bucket is full, filtering as we go
for i, kv := range getResp.Kvs {
if paging && int64(v.Len()) >= pred.Limit {
hasMore = true
break
}
lastKey = kv.Key
data, _, err := s.transformer.TransformFromStorage(ctx, kv.Value, authenticatedDataString(kv.Key))
if err != nil {
return storage.NewInternalErrorf("unable to transform key %q: %v", kv.Key, err)
}
if err := appendListItem(v, data, uint64(kv.ModRevision), pred, s.codec, s.versioner, newItemFunc); err != nil {
return err
}
numEvald++
// free kv early. Long lists can take O(seconds) to decode.
getResp.Kvs[i] = nil
}
// indicate to the client which resource version was returned
if returnedRV == 0 {
returnedRV = getResp.Header.Revision
}
// no more results remain or we didn't request paging
if !hasMore || !paging {
break
}
// we're paging but we have filled our bucket
if int64(v.Len()) >= pred.Limit {
break
}
if limit < maxLimit {
// We got incomplete result due to field/label selector dropping the object.
// Double page size to reduce total number of calls to etcd.
limit *= 2
if limit > maxLimit {
limit = maxLimit
}
*limitOption = clientv3.WithLimit(limit)
}
key = string(lastKey) + "\x00"
if withRev == 0 {
withRev = returnedRV
options = append(options, clientv3.WithRev(withRev))
}
}
// instruct the client to begin querying from immediately after the last key we returned
// we never return a key that the client wouldn't be allowed to see
if hasMore {
// we want to start immediately after the last key
next, err := storage.EncodeContinue(string(lastKey)+"\x00", keyPrefix, returnedRV)
if err != nil {
return err
}
var remainingItemCount *int64
// getResp.Count counts in objects that do not match the pred.
// Instead of returning inaccurate count for non-empty selectors, we return nil.
// Only set remainingItemCount if the predicate is empty.
if utilfeature.DefaultFeatureGate.Enabled(features.RemainingItemCount) {
if pred.Empty() {
c := int64(getResp.Count - pred.Limit)
remainingItemCount = &c
}
}
return s.versioner.UpdateList(listObj, uint64(returnedRV), next, remainingItemCount)
}
// no continuation
return s.versioner.UpdateList(listObj, uint64(returnedRV), "", nil)
}
// growSlice takes a slice value and grows its capacity up
// to the maximum of the passed sizes or maxCapacity, whichever
// is smaller. Above maxCapacity decisions about allocation are left
// to the Go runtime on append. This allows a caller to make an
// educated guess about the potential size of the total list while
// still avoiding overly aggressive initial allocation. If sizes
// is empty maxCapacity will be used as the size to grow.
func growSlice(v reflect.Value, maxCapacity int, sizes ...int) {
cap := v.Cap()
max := cap
for _, size := range sizes {
if size > max {
max = size
}
}
if len(sizes) == 0 || max > maxCapacity {
max = maxCapacity
}
if max <= cap {
return
}
if v.Len() > 0 {
extra := reflect.MakeSlice(v.Type(), v.Len(), max)
reflect.Copy(extra, v)
v.Set(extra)
} else {
extra := reflect.MakeSlice(v.Type(), 0, max)
v.Set(extra)
}
}
// Watch implements storage.Interface.Watch.
func (s *store) Watch(ctx context.Context, key string, opts storage.ListOptions) (watch.Interface, error) {
rev, err := s.versioner.ParseResourceVersion(opts.ResourceVersion)
if err != nil {
return nil, err
}
key = path.Join(s.pathPrefix, key)
return s.watcher.Watch(ctx, key, int64(rev), opts.Recursive, opts.ProgressNotify, opts.Predicate)
}
func (s *store) getState(ctx context.Context, getResp *clientv3.GetResponse, key string, v reflect.Value, ignoreNotFound bool) (*objState, error) {
state := &objState{
meta: &storage.ResponseMeta{},
}
if u, ok := v.Addr().Interface().(runtime.Unstructured); ok {
state.obj = u.NewEmptyInstance()
} else {
state.obj = reflect.New(v.Type()).Interface().(runtime.Object)
}
if len(getResp.Kvs) == 0 {
if !ignoreNotFound {
return nil, storage.NewKeyNotFoundError(key, 0)
}
if err := runtime.SetZeroValue(state.obj); err != nil {
return nil, err
}
} else {
data, stale, err := s.transformer.TransformFromStorage(ctx, getResp.Kvs[0].Value, authenticatedDataString(key))
if err != nil {
return nil, storage.NewInternalError(err.Error())
}
state.rev = getResp.Kvs[0].ModRevision
state.meta.ResourceVersion = uint64(state.rev)
state.data = data
state.stale = stale
if err := decode(s.codec, s.versioner, state.data, state.obj, state.rev); err != nil {
return nil, err
}
}
return state, nil
}
func (s *store) getStateFromObject(obj runtime.Object) (*objState, error) {
state := &objState{
obj: obj,
meta: &storage.ResponseMeta{},
}
rv, err := s.versioner.ObjectResourceVersion(obj)
if err != nil {
return nil, fmt.Errorf("couldn't get resource version: %v", err)
}
state.rev = int64(rv)
state.meta.ResourceVersion = uint64(state.rev)
// Compute the serialized form - for that we need to temporarily clean
// its resource version field (those are not stored in etcd).
if err := s.versioner.PrepareObjectForStorage(obj); err != nil {
return nil, fmt.Errorf("PrepareObjectForStorage failed: %v", err)
}
state.data, err = runtime.Encode(s.codec, obj)
if err != nil {
return nil, err
}
if err := s.versioner.UpdateObject(state.obj, uint64(rv)); err != nil {
klog.Errorf("failed to update object version: %v", err)
}
return state, nil
}
func (s *store) updateState(st *objState, userUpdate storage.UpdateFunc) (runtime.Object, uint64, error) {
ret, ttlPtr, err := userUpdate(st.obj, *st.meta)
if err != nil {
return nil, 0, err
}
if err := s.versioner.PrepareObjectForStorage(ret); err != nil {
return nil, 0, fmt.Errorf("PrepareObjectForStorage failed: %v", err)
}
var ttl uint64
if ttlPtr != nil {
ttl = *ttlPtr
}
return ret, ttl, nil
}
// ttlOpts returns client options based on given ttl.
// ttl: if ttl is non-zero, it will attach the key to a lease with ttl of roughly the same length
func (s *store) ttlOpts(ctx context.Context, ttl int64) ([]clientv3.OpOption, error) {
if ttl == 0 {
return nil, nil
}
id, err := s.leaseManager.GetLease(ctx, ttl)
if err != nil {
return nil, err
}
return []clientv3.OpOption{clientv3.WithLease(id)}, nil
}
// validateMinimumResourceVersion returns a 'too large resource' version error when the provided minimumResourceVersion is
// greater than the most recent actualRevision available from storage.
func (s *store) validateMinimumResourceVersion(minimumResourceVersion string, actualRevision uint64) error {
if minimumResourceVersion == "" {
return nil
}
minimumRV, err := s.versioner.ParseResourceVersion(minimumResourceVersion)
if err != nil {
return apierrors.NewBadRequest(fmt.Sprintf("invalid resource version: %v", err))
}
// Enforce the storage.Interface guarantee that the resource version of the returned data
// "will be at least 'resourceVersion'".
if minimumRV > actualRevision {
return storage.NewTooLargeResourceVersionError(minimumRV, actualRevision, 0)
}
return nil
}
// decode decodes value of bytes into object. It will also set the object resource version to rev.
// On success, objPtr would be set to the object.
func decode(codec runtime.Codec, versioner storage.Versioner, value []byte, objPtr runtime.Object, rev int64) error {
if _, err := conversion.EnforcePtr(objPtr); err != nil {
return fmt.Errorf("unable to convert output object to pointer: %v", err)
}
_, _, err := codec.Decode(value, nil, objPtr)
if err != nil {
return err
}
// being unable to set the version does not prevent the object from being extracted
if err := versioner.UpdateObject(objPtr, uint64(rev)); err != nil {
klog.Errorf("failed to update object version: %v", err)
}
return nil
}
// appendListItem decodes and appends the object (if it passes filter) to v, which must be a slice.
func appendListItem(v reflect.Value, data []byte, rev uint64, pred storage.SelectionPredicate, codec runtime.Codec, versioner storage.Versioner, newItemFunc func() runtime.Object) error {
obj, _, err := codec.Decode(data, nil, newItemFunc())
if err != nil {
return err
}
// being unable to set the version does not prevent the object from being extracted
if err := versioner.UpdateObject(obj, rev); err != nil {
klog.Errorf("failed to update object version: %v", err)
}
if matched, err := pred.Matches(obj); err == nil && matched {
v.Set(reflect.Append(v, reflect.ValueOf(obj).Elem()))
}
return nil
}
func notFound(key string) clientv3.Cmp {
return clientv3.Compare(clientv3.ModRevision(key), "=", 0)
}
// getTypeName returns type name of an object for reporting purposes.
func getTypeName(obj interface{}) string {
return reflect.TypeOf(obj).String()
}
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