Update go.mod to require the latest version of logr

remove unreachable if statement, and typo

Check new klog flag's prefix

The ::add-path:: command was
disabled (https://github.blog/changelog/2020-10-01-github-actions-deprecating-set-env-and-add-path-commands/). One
possible replacement should be to modify the content of
$GITHUB_ENV (https://docs.github.com/en/free-pro-team@latest/actions/reference/workflow-commands-for-github-actions#setting-an-environment-variable).

github: fix apidiff check

Commit 29a2d64 bumped logr in go.mod without the corresponding change
in go.sum, with the result that any go invocation (for example "go
test .") leads to a modified repo.

fix go.sum

This is needed for wrappers like klogr which need to skip additional
levels in the call stack.

Error(), WithName() and sorting were not tested before.

Now that klog has support for structured logging, it makes sense to
use that also through klogr. The log output without a structured
logger becomes more readable and key/value semantic is not lost
anymore with a structured logger.

However, revising the output handling is a breaking change for those
who depend on the traditional output. Therefore this is implemented in
a backward compatible way:
- code calling New() without parameters continues to work and
  gets the traditional behavior
- deferring the complete output handling to klog is enabled
  via a functional option

Adding the optional options to New breaks code which assigns New to a
function pointer of the original type without options.

To avoid that, a new NewWithOptions gets added. That new function can
also use the better default of letting klog serialize key/value pairs.

Signed-off-by: Li Zhijian <[email protected]>

klogr output format

This implements WithCallDepth from logr v0.4.0 in klogr.

klogr call depth

test: cleanup temporary file