golangci-lint failure

[andyzhangx]

https://github.com/kubernetes-csi/csi-driver-iscsi/runs/4329568959?check_suite_focus=true

run golangci-lint
  Running [/home/runner/golangci-lint-1.29.0-linux-amd64/golangci-lint run --out-format=github-actions -E=gofmt,golint,misspell --timeout=30m0s] in [] ...
  Error: Error return value of `iscsiLib.Disconnect` is not checked (errcheck)
  Error: Error return value of `server.Serve` is not checked (errcheck)
  Error: Error return value of `flag.Set` is not checked (errcheck)
  Error: Error return value of `flag.CommandLine.Parse` is not checked (errcheck)
  Error: Error return value of `cmd.MarkPersistentFlagRequired` is not checked (errcheck)
  Error: Error return value of `cmd.MarkPersistentFlagRequired` is not checked (errcheck)
  Error: exported func NewDriver returns unexported type *github.com/kubernetes-csi/csi-driver-iscsi/pkg/iscsi.driver, which can be annoying to use (golint)
  Error: exported func NewNodeServer returns unexported type *github.com/kubernetes-csi/csi-driver-iscsi/pkg/iscsi.nodeServer, which can be annoying to use (golint)
  Error: type name will be used as iscsi.ISCSIUtil by other packages, and that stutters; consider calling this Util (golint)
  Error: `ns` is unused (structcheck)
  Error: S1023: redundant `return` statement (gosimple)
  Error: S1023: redundant `return` statement (gosimple)
  
  Error: issues found
  Ran golangci-lint in 109779ms

[andyzhangx]

name: Static Checks
on:
    pull_request: {}
    push: {}
jobs:
    go_lint:
        name: Go Lint
        runs-on: ubuntu-18.04
        steps:
            - name: Checkout code
              uses: actions/checkout@master
            - name: Run linter
              uses: golangci/golangci-lint-action@v2
              with:
                  version: v1.29
                  args: -E=gofmt,golint,misspell --timeout=30m0s

[andyzhangx]

~/go/src/github.com/kubernetes-csi/csi-driver-iscsi# hack/verify-golint.sh
Verifying golint
pkg/iscsi/driver.go:31:2: `ns` is unused (structcheck)
        ns *nodeServer
        ^
pkg/iscsi/iscsi_util.go:112:21: Error return value of `iscsiLib.Disconnect` is not checked (errcheck)
        iscsiLib.Disconnect(connector.TargetIqn, connector.TargetPortals)
                           ^
pkg/iscsi/server.go:110:14: Error return value of `server.Serve` is not checked (errcheck)
        server.Serve(listener)
                    ^
cmd/iscsiplugin/main.go:36:10: Error return value of `flag.Set` is not checked (errcheck)
        flag.Set("logtostderr", "true")
                ^
cmd/iscsiplugin/main.go:41:24: Error return value of `flag.CommandLine.Parse` is not checked (errcheck)
        flag.CommandLine.Parse([]string{})
                              ^
cmd/iscsiplugin/main.go:56:32: Error return value of `cmd.MarkPersistentFlagRequired` is not checked (errcheck)
        cmd.MarkPersistentFlagRequired("nodeid")
                                      ^
cmd/iscsiplugin/main.go:59:32: Error return value of `cmd.MarkPersistentFlagRequired` is not checked (errcheck)
        cmd.MarkPersistentFlagRequired("endpoint")
                                      ^
pkg/iscsi/driver.go:45:41: exported func NewDriver returns unexported type *github.com/kubernetes-csi/csi-driver-iscsi/pkg/iscsi.driver, which can be annoying to use (golint)
func NewDriver(nodeID, endpoint string) *driver {
                                        ^
pkg/iscsi/driver.go:64:31: exported func NewNodeServer returns unexported type *github.com/kubernetes-csi/csi-driver-iscsi/pkg/iscsi.nodeServer, which can be annoying to use (golint)
func NewNodeServer(d *driver) *nodeServer {
                              ^
pkg/iscsi/iscsi_util.go:29:6: type name will be used as iscsi.ISCSIUtil by other packages, and that stutters; consider calling this Util (golint)
type ISCSIUtil struct{}
     ^
pkg/iscsi/driver.go:101:2: S1023: redundant `return` statement (gosimple)
        return
        ^
pkg/iscsi/server.go:58:2: S1023: redundant `return` statement (gosimple)
        return
        ^