// ListAndWatch first lists all items and get the resource version at the moment of call,
// and then use the resource version to watch.
// It returns error if ListAndWatch didn't even try to initialize watch.
func (r *Reflector) ListAndWatch(stopCh <-chan struct{}) error {
glog.V(3).Infof("Listing and watching %v from %s", r.expectedType, r.name)
var resourceVersion string
resyncCh, cleanup := r.resyncChan()
defer cleanup()
// Explicitly set "0" as resource version - it's fine for the List()
// to be served from cache and potentially be delayed relative to
// etcd contents. Reflector framework will catch up via Watch() eventually.
options := v1.ListOptions{ResourceVersion: "0"}
list, err := r.listerWatcher.List(options)
if err != nil {
return fmt.Errorf("%s: Failed to list %v: %v", r.name, r.expectedType, err)
}
listMetaInterface, err := meta.ListAccessor(list)
if err != nil {
return fmt.Errorf("%s: Unable to understand list result %#v: %v", r.name, list, err)
}
resourceVersion = listMetaInterface.GetResourceVersion()
items, err := meta.ExtractList(list)
if err != nil {
return fmt.Errorf("%s: Unable to understand list result %#v (%v)", r.name, list, err)
}
if err := r.syncWith(items, resourceVersion); err != nil {
return fmt.Errorf("%s: Unable to sync list result: %v", r.name, err)
}
r.setLastSyncResourceVersion(resourceVersion)
resyncerrc := make(chan error, 1)
cancelCh := make(chan struct{})
defer close(cancelCh)
go func() {
for {
select {
case <-resyncCh:
case <-stopCh:
return
case <-cancelCh:
return
}
glog.V(4).Infof("%s: forcing resync", r.name)
if err := r.store.Resync(); err != nil {
resyncerrc <- err
return
}
cleanup()
resyncCh, cleanup = r.resyncChan()
}
}()
for {
timemoutseconds := int64(minWatchTimeout.Seconds() * (rand.Float64() + 1.0))
options = v1.ListOptions{
ResourceVersion: resourceVersion,
// We want to avoid situations of hanging watchers. Stop any wachers that do not
// receive any events within the timeout window.
TimeoutSeconds: &timemoutseconds,
}
w, err := r.listerWatcher.Watch(options)
if err != nil {
switch err {
case io.EOF:
// watch closed normally
case io.ErrUnexpectedEOF:
glog.V(1).Infof("%s: Watch for %v closed with unexpected EOF: %v", r.name, r.expectedType, err)
default:
utilruntime.HandleError(fmt.Errorf("%s: Failed to watch %v: %v", r.name, r.expectedType, err))
}
// If this is "connection refused" error, it means that most likely apiserver is not responsive.
// It doesn't make sense to re-list all objects because most likely we will be able to restart
// watch where we ended.
// If that's the case wait and resend watch request.
if urlError, ok := err.(*url.Error); ok {
if opError, ok := urlError.Err.(*net.OpError); ok {
if errno, ok := opError.Err.(syscall.Errno); ok && errno == syscall.ECONNREFUSED {
time.Sleep(time.Second)
continue
}
}
}
return nil
}
if err := r.watchHandler(w, &resourceVersion, resyncerrc, stopCh); err != nil {
if err != errorStopRequested {
glog.Warningf("%s: watch of %v ended with: %v", r.name, r.expectedType, err)
}
return nil
}
}
}
// TODO: check for watch expired error and retry watch from latest point? Same issue exists for Until.
func ListWatchUntil(timeout time.Duration, lw ListerWatcher, conditions ...watch.ConditionFunc) (*watch.Event, error) {
if len(conditions) == 0 {
return nil, nil
}
list, err := lw.List(v1.ListOptions{})
if err != nil {
return nil, err
}
initialItems, err := meta.ExtractList(list)
if err != nil {
return nil, err
}
// use the initial items as simulated "adds"
var lastEvent *watch.Event
currIndex := 0
passedConditions := 0
for _, condition := range conditions {
// check the next condition against the previous event and short circuit waiting for the next watch
if lastEvent != nil {
done, err := condition(*lastEvent)
if err != nil {
return lastEvent, err
}
if done {
passedConditions = passedConditions + 1
continue
}
}
ConditionSucceeded:
for currIndex < len(initialItems) {
lastEvent = &watch.Event{Type: watch.Added, Object: initialItems[currIndex]}
currIndex++
done, err := condition(*lastEvent)
if err != nil {
return lastEvent, err
}
if done {
passedConditions = passedConditions + 1
break ConditionSucceeded
}
}
}
if passedConditions == len(conditions) {
return lastEvent, nil
}
remainingConditions := conditions[passedConditions:]
metaObj, err := meta.ListAccessor(list)
if err != nil {
return nil, err
}
currResourceVersion := metaObj.GetResourceVersion()
watchInterface, err := lw.Watch(v1.ListOptions{ResourceVersion: currResourceVersion})
if err != nil {
return nil, err
}
return watch.Until(timeout, watchInterface, remainingConditions...)
}
// GetReference returns an ObjectReference which refers to the given
// object, or an error if the object doesn't follow the conventions
// that would allow this.
// TODO: should take a meta.Interface see http://issue.k8s.io/7127
func GetReference(obj runtime.Object) (*ObjectReference, error) {
if obj == nil {
return nil, ErrNilObject
}
if ref, ok := obj.(*ObjectReference); ok {
// Don't make a reference to a reference.
return ref, nil
}
gvk := obj.GetObjectKind().GroupVersionKind()
// if the object referenced is actually persisted, we can just get kind from meta
// if we are building an object reference to something not yet persisted, we should fallback to scheme
kind := gvk.Kind
if len(kind) == 0 {
// TODO: this is wrong
gvks, _, err := api.Scheme.ObjectKinds(obj)
if err != nil {
return nil, err
}
kind = gvks[0].Kind
}
// An object that implements only List has enough metadata to build a reference
var listMeta meta.List
objectMeta, err := meta.Accessor(obj)
if err != nil {
listMeta, err = meta.ListAccessor(obj)
if err != nil {
return nil, err
}
} else {
listMeta = objectMeta
}
// if the object referenced is actually persisted, we can also get version from meta
version := gvk.GroupVersion().String()
if len(version) == 0 {
selfLink := listMeta.GetSelfLink()
if len(selfLink) == 0 {
return nil, ErrNoSelfLink
}
selfLinkUrl, err := url.Parse(selfLink)
if err != nil {
return nil, err
}
// example paths: /<prefix>/<version>/*
parts := strings.Split(selfLinkUrl.Path, "/")
if len(parts) < 3 {
return nil, fmt.Errorf("unexpected self link format: '%v'; got version '%v'", selfLink, version)
}
version = parts[2]
}
// only has list metadata
if objectMeta == nil {
return &ObjectReference{
Kind: kind,
APIVersion: version,
ResourceVersion: listMeta.GetResourceVersion(),
}, nil
}
return &ObjectReference{
Kind: kind,
APIVersion: version,
Name: objectMeta.GetName(),
Namespace: objectMeta.GetNamespace(),
UID: objectMeta.GetUID(),
ResourceVersion: objectMeta.GetResourceVersion(),
}, nil
}
// RunGet implements the generic Get command
// TODO: convert all direct flag accessors to a struct and pass that instead of cmd
func RunGet(f cmdutil.Factory, out, errOut io.Writer, cmd *cobra.Command, args []string, options *GetOptions) error {
if len(options.Raw) > 0 {
restClient, err := f.RESTClient()
if err != nil {
return err
}
stream, err := restClient.Get().RequestURI(options.Raw).Stream()
if err != nil {
return err
}
defer stream.Close()
_, err = io.Copy(out, stream)
if err != nil && err != io.EOF {
return err
}
return nil
}
selector := cmdutil.GetFlagString(cmd, "selector")
allNamespaces := cmdutil.GetFlagBool(cmd, "all-namespaces")
showKind := cmdutil.GetFlagBool(cmd, "show-kind")
mapper, typer, err := f.UnstructuredObject()
if err != nil {
return err
}
filterFuncs := f.DefaultResourceFilterFunc()
filterOpts := f.DefaultResourceFilterOptions(cmd, allNamespaces)
cmdNamespace, enforceNamespace, err := f.DefaultNamespace()
if err != nil {
return err
}
if allNamespaces {
enforceNamespace = false
}
if len(args) == 0 && cmdutil.IsFilenameEmpty(options.Filenames) {
fmt.Fprint(errOut, "You must specify the type of resource to get. ", valid_resources)
fullCmdName := cmd.Parent().CommandPath()
usageString := "Required resource not specified."
if len(fullCmdName) > 0 && cmdutil.IsSiblingCommandExists(cmd, "explain") {
usageString = fmt.Sprintf("%s\nUse \"%s explain <resource>\" for a detailed description of that resource (e.g. %[2]s explain pods).", usageString, fullCmdName)
}
return cmdutil.UsageError(cmd, usageString)
}
argsHasNames, err := resource.HasNames(args)
if err != nil {
return err
}
// always show resources when getting by name or filename, or if the output
// is machine-consumable, or if multiple resource kinds were requested.
if len(options.Filenames) > 0 || argsHasNames || cmdutil.OutputsRawFormat(cmd) {
if !cmd.Flag("show-all").Changed {
cmd.Flag("show-all").Value.Set("true")
}
}
export := cmdutil.GetFlagBool(cmd, "export")
// handle watch separately since we cannot watch multiple resource types
isWatch, isWatchOnly := cmdutil.GetFlagBool(cmd, "watch"), cmdutil.GetFlagBool(cmd, "watch-only")
if isWatch || isWatchOnly {
r := resource.NewBuilder(mapper, typer, resource.ClientMapperFunc(f.UnstructuredClientForMapping), unstructured.UnstructuredJSONScheme).
NamespaceParam(cmdNamespace).DefaultNamespace().AllNamespaces(allNamespaces).
FilenameParam(enforceNamespace, &options.FilenameOptions).
SelectorParam(selector).
ExportParam(export).
ResourceTypeOrNameArgs(true, args...).
SingleResourceType().
Latest().
Do()
err := r.Err()
if err != nil {
return err
}
infos, err := r.Infos()
if err != nil {
return err
}
if len(infos) != 1 {
return i18n.Errorf("watch is only supported on individual resources and resource collections - %d resources were found", len(infos))
}
info := infos[0]
mapping := info.ResourceMapping()
printer, err := f.PrinterForMapping(cmd, mapping, allNamespaces)
if err != nil {
return err
}
obj, err := r.Object()
if err != nil {
return err
}
// watching from resourceVersion 0, starts the watch at ~now and
// will return an initial watch event. Starting form ~now, rather
// the rv of the object will insure that we start the watch from
// inside the watch window, which the rv of the object might not be.
rv := "0"
isList := meta.IsListType(obj)
if isList {
// the resourceVersion of list objects is ~now but won't return
// an initial watch event
rv, err = mapping.MetadataAccessor.ResourceVersion(obj)
if err != nil {
return err
}
}
// print the current object
filteredResourceCount := 0
if !isWatchOnly {
if err := printer.PrintObj(obj, out); err != nil {
return fmt.Errorf("unable to output the provided object: %v", err)
}
filteredResourceCount++
cmdutil.PrintFilterCount(filteredResourceCount, mapping.Resource, filterOpts)
}
// print watched changes
w, err := r.Watch(rv)
if err != nil {
return err
}
first := true
filteredResourceCount = 0
intr := interrupt.New(nil, w.Stop)
intr.Run(func() error {
_, err := watch.Until(0, w, func(e watch.Event) (bool, error) {
if !isList && first {
// drop the initial watch event in the single resource case
first = false
return false, nil
}
err := printer.PrintObj(e.Object, out)
if err != nil {
return false, err
}
filteredResourceCount++
cmdutil.PrintFilterCount(filteredResourceCount, mapping.Resource, filterOpts)
return false, nil
})
return err
})
return nil
}
r := resource.NewBuilder(mapper, typer, resource.ClientMapperFunc(f.UnstructuredClientForMapping), unstructured.UnstructuredJSONScheme).
NamespaceParam(cmdNamespace).DefaultNamespace().AllNamespaces(allNamespaces).
FilenameParam(enforceNamespace, &options.FilenameOptions).
SelectorParam(selector).
ExportParam(export).
ResourceTypeOrNameArgs(true, args...).
ContinueOnError().
Latest().
Flatten().
Do()
err = r.Err()
if err != nil {
return err
}
printer, generic, err := cmdutil.PrinterForCommand(cmd)
if err != nil {
return err
}
if generic {
// we flattened the data from the builder, so we have individual items, but now we'd like to either:
// 1. if there is more than one item, combine them all into a single list
// 2. if there is a single item and that item is a list, leave it as its specific list
// 3. if there is a single item and it is not a a list, leave it as a single item
var errs []error
singleItemImplied := false
infos, err := r.IntoSingleItemImplied(&singleItemImplied).Infos()
if err != nil {
if singleItemImplied {
return err
}
errs = append(errs, err)
}
if len(infos) == 0 && len(errs) == 0 {
outputEmptyListWarning(errOut)
}
res := ""
if len(infos) > 0 {
res = infos[0].ResourceMapping().Resource
}
var obj runtime.Object
if !singleItemImplied || len(infos) > 1 {
// we have more than one item, so coerce all items into a list
list := &unstructured.UnstructuredList{
Object: map[string]interface{}{
"kind": "List",
"apiVersion": "v1",
"metadata": map[string]interface{}{},
},
}
for _, info := range infos {
list.Items = append(list.Items, info.Object.(*unstructured.Unstructured))
}
obj = list
} else {
obj = infos[0].Object
}
isList := meta.IsListType(obj)
if isList {
filteredResourceCount, items, err := cmdutil.FilterResourceList(obj, filterFuncs, filterOpts)
if err != nil {
return err
}
// take the filtered items and create a new list for display
list := &unstructured.UnstructuredList{
Object: map[string]interface{}{
"kind": "List",
"apiVersion": "v1",
"metadata": map[string]interface{}{},
},
}
if listMeta, err := meta.ListAccessor(obj); err == nil {
list.Object["selfLink"] = listMeta.GetSelfLink()
list.Object["resourceVersion"] = listMeta.GetResourceVersion()
}
for _, item := range items {
list.Items = append(list.Items, item.(*unstructured.Unstructured))
}
if err := printer.PrintObj(list, out); err != nil {
errs = append(errs, err)
}
cmdutil.PrintFilterCount(filteredResourceCount, res, filterOpts)
return utilerrors.Reduce(utilerrors.Flatten(utilerrors.NewAggregate(errs)))
}
filteredResourceCount := 0
if isFiltered, err := filterFuncs.Filter(obj, filterOpts); !isFiltered {
if err != nil {
glog.V(2).Infof("Unable to filter resource: %v", err)
} else if err := printer.PrintObj(obj, out); err != nil {
errs = append(errs, err)
}
} else if isFiltered {
filteredResourceCount++
}
cmdutil.PrintFilterCount(filteredResourceCount, res, filterOpts)
return utilerrors.Reduce(utilerrors.Flatten(utilerrors.NewAggregate(errs)))
}
allErrs := []error{}
errs := sets.NewString()
infos, err := r.Infos()
if err != nil {
allErrs = append(allErrs, err)
}
if len(infos) == 0 && len(allErrs) == 0 {
outputEmptyListWarning(errOut)
}
objs := make([]runtime.Object, len(infos))
for ix := range infos {
objs[ix] = infos[ix].Object
}
sorting, err := cmd.Flags().GetString("sort-by")
if err != nil {
return err
}
var sorter *kubectl.RuntimeSort
if len(sorting) > 0 && len(objs) > 1 {
// TODO: questionable
if sorter, err = kubectl.SortObjects(f.Decoder(true), objs, sorting); err != nil {
return err
}
}
// use the default printer for each object
printer = nil
var lastMapping *meta.RESTMapping
w := kubectl.GetNewTabWriter(out)
filteredResourceCount := 0
if resource.MultipleTypesRequested(args) || cmdutil.MustPrintWithKinds(objs, infos, sorter) {
showKind = true
}
for ix := range objs {
var mapping *meta.RESTMapping
var original runtime.Object
if sorter != nil {
mapping = infos[sorter.OriginalPosition(ix)].Mapping
original = infos[sorter.OriginalPosition(ix)].Object
} else {
mapping = infos[ix].Mapping
original = infos[ix].Object
}
if printer == nil || lastMapping == nil || mapping == nil || mapping.Resource != lastMapping.Resource {
if printer != nil {
w.Flush()
cmdutil.PrintFilterCount(filteredResourceCount, lastMapping.Resource, filterOpts)
}
printer, err = f.PrinterForMapping(cmd, mapping, allNamespaces)
if err != nil {
if !errs.Has(err.Error()) {
errs.Insert(err.Error())
allErrs = append(allErrs, err)
}
continue
}
// add linebreak between resource groups (if there is more than one)
// skip linebreak above first resource group
noHeaders := cmdutil.GetFlagBool(cmd, "no-headers")
if lastMapping != nil && !noHeaders {
fmt.Fprintf(errOut, "%s\n", "")
}
lastMapping = mapping
}
// try to convert before apply filter func
decodedObj, _ := kubectl.DecodeUnknownObject(original)
// filter objects if filter has been defined for current object
if isFiltered, err := filterFuncs.Filter(decodedObj, filterOpts); isFiltered {
if err == nil {
filteredResourceCount++
continue
}
if !errs.Has(err.Error()) {
errs.Insert(err.Error())
allErrs = append(allErrs, err)
}
}
if resourcePrinter, found := printer.(*kubectl.HumanReadablePrinter); found {
resourceName := resourcePrinter.GetResourceKind()
if mapping != nil {
if resourceName == "" {
resourceName = mapping.Resource
}
if alias, ok := kubectl.ResourceShortFormFor(mapping.Resource); ok {
resourceName = alias
} else if resourceName == "" {
resourceName = "none"
}
} else {
resourceName = "none"
}
if showKind {
resourcePrinter.EnsurePrintWithKind(resourceName)
}
if err := printer.PrintObj(decodedObj, w); err != nil {
if !errs.Has(err.Error()) {
errs.Insert(err.Error())
allErrs = append(allErrs, err)
}
}
continue
}
if err := printer.PrintObj(decodedObj, w); err != nil {
if !errs.Has(err.Error()) {
errs.Insert(err.Error())
allErrs = append(allErrs, err)
}
continue
}
}
w.Flush()
if printer != nil && lastMapping != nil {
cmdutil.PrintFilterCount(filteredResourceCount, lastMapping.Resource, filterOpts)
}
return utilerrors.NewAggregate(allErrs)
}