243e655161
Automatic merge from submit-queue (batch tested with PRs 50208, 50259, 49702, 50267, 48986) Relax restrictions on environment variable names. Fixes #2707 The POSIX standard restricts environment variable names to uppercase letters, digits, and the underscore character in shell contexts only. For generic application usage, it is stated that all other characters shall be tolerated. (Reference [here](http://pubs.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap08.html), my prose reasoning [here](https://github.com/kubernetes/kubernetes/issues/2707#issuecomment-285309156).) This change relaxes the rules to some degree. Namely, we stop requiring environment variable names to be strict `C_IDENTIFIERS` and start permitting lowercase, dot, and dash characters. Public container images using environment variable names beyond the shell-only context can benefit from this relaxation. Elasticsearch is one popular example.
External Repository Staging Area
This directory is the staging area for packages that have been split to their own repository. The content here will be periodically published to respective top-level k8s.io repositories.
Repositories currently staged here:
k8s.io/apiextensions-apiserverk8s.io/apik8s.io/apimachineryk8s.io/apiserverk8s.io/client-gok8s.io/kube-aggregatork8s.io/kube-gen(about to be published)k8s.io/metricsk8s.io/sample-apiserver
The code in the staging/ directory is authoritative, i.e. the only copy of the code. You can directly modify such code.
Using staged repositories from Kubernetes code
Kubernetes code uses the repositories in this directory via symlinks in the
vendor/k8s.io directory into this staging area. For example, when
Kubernetes code imports a package from the k8s.io/client-go repository, that
import is resolved to staging/src/k8s.io/client-go relative to the project
root:
// pkg/example/some_code.go
package example
import (
"k8s.io/client-go/dynamic" // resolves to staging/src/k8s.io/client-go/dynamic
)
Once the change-over to external repositories is complete, these repositories
will actually be vendored from k8s.io/<package-name>.