Production-Grade Container Scheduling and Management
Go to file
Kubernetes Submit Queue 2cbb07a439
Merge pull request #55871 from atlassian/unstructured-converter-no-mutation
Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Fix potential unexpected object mutation that can lead to data races

**What this PR does / why we need it**:
In #51526 I introduced an optimization - do a deep copy instead of to and from JSON roundtrip to convert anything that implements `runtime.Unstructured`. I just discovered that the method that is used there `UnstructuredContent()` in both `Unstructured` and `UnstructuredList` may mutate the original object.
2008750398/staging/src/k8s.io/apimachinery/pkg/apis/meta/v1/unstructured/unstructured.go (L87-L92)
7c10cbc642/staging/src/k8s.io/apimachinery/pkg/apis/meta/v1/unstructured/unstructured_list.go (L58-L75)
This is problematic because previously (before #51526) there was no mutation and because this is unexpected and may lead to data races - it is bad behaviour to mutate original object when you just want a copy of it.
This PR fixes the issue.

Without the fix the tests I've added are failing because when comparison is done original object is not the same:
```
converter_test.go:154: Object changed, diff: 
object.Object[items]:
  a: []interface {}{}
  b: <nil>
converter_test.go:154: Object changed, diff: 
object.Object[items]:
  a: []interface {}{map[string]interface {}{"kind":"Pod"}}
  b: <nil>
```

However the underlying issue is not fixed here - `UnstructuredContent()` is brittle and dangerous. Method name does not imply that it mutates data when you call it. And godoc does not mention that either:
509df603b1/staging/src/k8s.io/apimachinery/pkg/runtime/interfaces.go (L233-L249)
Something needs to be done about it IMO.
Also `UnstructuredContent()` implementation in `UnstructuredList` does not implement the behaviour required by godoc in `runtime.Unstructured`.

**Release note**:
```release-note
NONE
```
/kind bug
/sig api-machinery
/assign @sttts
2017-11-20 08:58:37 -08:00
.github
api Merge pull request #51530 from rootfs/iscsi-pv-ns 2017-11-18 16:38:36 -08:00
build Merge pull request #54938 from nikhita/kubectl-explain-trailing-period 2017-11-18 04:02:57 -08:00
cluster Merge pull request #55990 from hyperbolic2346/rollup 2017-11-20 04:50:03 -08:00
cmd admission/webhook: move webhook initializer into plugin 2017-11-20 09:28:42 +01:00
docs Merge pull request #51530 from rootfs/iscsi-pv-ns 2017-11-18 16:38:36 -08:00
examples
Godeps Merge pull request #55496 from JiangtianLi/jiangtli-fixservercore 2017-11-18 10:46:38 -08:00
hack Merge pull request #54007 from vishh/hack-owners 2017-11-18 23:08:05 -08:00
logo
pkg Merge pull request #54701 from mattjmcnaughton/mattjmcnaughton/53728-clean-up-reconcileAutoscaling 2017-11-20 08:16:26 -08:00
plugin admission/webhook: move webhook initializer into plugin 2017-11-20 09:28:42 +01:00
staging Merge pull request #55871 from atlassian/unstructured-converter-no-mutation 2017-11-20 08:58:37 -08:00
test Merge pull request #55871 from atlassian/unstructured-converter-no-mutation 2017-11-20 08:58:37 -08:00
third_party
translations Merge pull request #47584 from zjj2wry/translate 2017-11-15 23:57:28 -08:00
vendor Merge pull request #55496 from JiangtianLi/jiangtli-fixservercore 2017-11-18 10:46:38 -08:00
.bazelrc
.generated_files
.gitattributes
.gitignore
.kazelcfg.json
BUILD.bazel
CHANGELOG-1.2.md
CHANGELOG-1.3.md
CHANGELOG-1.4.md
CHANGELOG-1.5.md
CHANGELOG-1.6.md
CHANGELOG-1.7.md
CHANGELOG-1.8.md
CHANGELOG-1.9.md
CHANGELOG.md
code-of-conduct.md
CONTRIBUTING.md
labels.yaml
LICENSE
Makefile
Makefile.generated_files
OWNERS
OWNERS_ALIASES
README.md
SUPPORT.md
Vagrantfile
WORKSPACE

Kubernetes

Submit Queue Widget GoDoc Widget CII Best Practices


Kubernetes is an open source system for managing containerized applications across multiple hosts, providing basic mechanisms for deployment, maintenance, and scaling of applications.

Kubernetes builds upon a decade and a half of experience at Google running production workloads at scale using a system called Borg, combined with best-of-breed ideas and practices from the community.

Kubernetes is hosted by the Cloud Native Computing Foundation (CNCF). If you are a company that wants to help shape the evolution of technologies that are container-packaged, dynamically-scheduled and microservices-oriented, consider joining the CNCF. For details about who's involved and how Kubernetes plays a role, read the CNCF announcement.


To start using Kubernetes

See our documentation on kubernetes.io.

Try our interactive tutorial.

Take a free course on Scalable Microservices with Kubernetes.

To start developing Kubernetes

The community repository hosts all information about building Kubernetes from source, how to contribute code and documentation, who to contact about what, etc.

If you want to build Kubernetes right away there are two options:

You have a working Go environment.
$ go get -d k8s.io/kubernetes
$ cd $GOPATH/src/k8s.io/kubernetes
$ make
You have a working Docker environment.
$ git clone https://github.com/kubernetes/kubernetes
$ cd kubernetes
$ make quick-release

If you are less impatient, head over to the developer's documentation.

Support

If you need support, start with the troubleshooting guide and work your way through the process that we've outlined.

That said, if you have questions, reach out to us one way or another.

Analytics