Add the examples to demo listing/creating pods

[ityuhui]

Add two examples to demo how to use the c client library:

• Create a pod
• List pods

Because now kuberentes-client/c has no utility such as "config" functions in addition to the source code generated by OpenAPI c generator, these two examples implement the config utility functions in their own source code.

int loadK8sConfigInCluster(char *token, int token_buf_size);
int init_k8s_connector(const char *token_out_of_cluster);

After this PR, I will implement and integrate the config utility to kuberentes-client/c. the same as other language client libraries.

[ityuhui]

/cc @brendandburns

[brendandburns]

Thanks for the examples!

I think we need to adopt a style guide for this repo, and add some validation testing to ensure that code matches the style guide.

Do you have any suggestions for a good C style guide? Perhaps Gnu Indent (https://www.gnu.org/software/indent/)

[ityuhui]

@brendandburns Thank you for your review. I will update the code by your comment.

And I agree that we should adopt a style guide for this repo. Let me learn and try Gnu Indent.

[ityuhui]

Hi @brendandburns

Do you have a preferred GNU Indent parameter list ? (e.g. -npro -nip -nlp -npsl -i4 -ts4 -sob -l200 -ss -bl -bli 0)

If not, I will prepare a parameter list for your review.

[brendandburns]

I don't have a preferred parameter list, let's start with what you suggest.

[brendandburns]

Sounds great, let me know when this PR is ready to review again.

Thanks!

[ityuhui]

Hi @brendandburns

I have prepared a parameter list of GNU Indent for your review:

Parameter List

-npro -nbad -nip -lp -npsl -npcs -i4 -ts4 -sob -br -ce -nut -bap -nbc -bbo -brs -cs -nfc1 -nfca -hnl -ip0 -nprs -saf -sai -saw -ci4 -cli0 -l200

Detail Description

Option	Description
-npro	Do not read ‘.indent.pro’ files.
-nbad	Do not force blank lines after declarations.
-nip	Zero width indentation for parameters.
-lp	Line up continued lines at parentheses.
-npsl	Put the type of a procedure on the same line as its name.
-npcs	Do not put space after the function in function calls.
-i4	Set indentation level to 4 spaces.
-ts4	Set tab size to 4 spaces.
-sob	Swallow optional blank lines.
-br	Put braces on line with if, etc.
-ce	Cuddle else and preceding ‘}’.
-nut	Use spaces instead of tabs.
-bap	Force blank lines after procedure bodies.
-nbc	Do not force newlines after commas in declarations.
-bbo	Prefer to break long lines before boolean operators.
-brs	Put braces on struct declaration line.
-cs	Put a space after a cast operator.
-nfc1	Do not format comments in the first column as normal.
-nfca	Do not format any comments.
-hnl	Prefer to break long lines at the position of newlines in the input.
-ip0	Indent parameter types in old-style function definitions by 0 spaces.
-nprs	Do not put a space after every '(' and before every ')'.
-saf	Put a space after each for.
-sai	Put a space after each if.
-saw	Put a space after each while.
-ci4	Continuation indent of 4 spaces.
-cli0	Case label indent of 0 spaces.
-l200	Set maximum line length for non-comment lines to 200.

Reference

GNU Indent Document

New Example Code

I have used GNU Indent with this parameter list to generate the new example source code and pushed them here for review again.

[brendandburns]

Looks great!

/lgtm /approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: brendandburns, ityuhui

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