refactor: Avoid using API tojson and tojenkinsfile

Created by: bunnymiao

What type of PR is this?

/kind feature

What this PR does / why we need it:

This PR avoids using API tojson and tojenkinsfile

Which issue(s) this PR fixes:

Fixes #714

Special notes for reviewers:

Does this PR introduced a user-facing change?

NONE

Additional documentation, usage docs, etc.: