* ci: add Lint check on commits
* ci: fix Lint script error
* test: fix go vet errors
* test: fix go vet errors, remove gofumpt to check go vet
* test: fix go vet errors, try gofumpt
* test: fix go vet errors, try gofumpt, round 1
* test: fix go vet errors, try gofumpt, round 2
* ci: fix Lint errors
* implement k8s service discovery
* simplify code
* use default namespace if not provided
* disable codecov bot comment
* ignore adhoc dir
* simplify building target in NewClient
* reformat code
* Fix filepath (#990)
* format code, and reorg imports (#991)
* add more unit test
Co-authored-by: anqiansong <anqiansong@gmail.com>