style: fix lints

Signed-off-by: Hunter Gregory <[email protected]>

npm/pkg/dataplane/policies/chain-management_linux.go

@@ -26,6 +26,8 @@ const (
 	minLineNumberStringLength int = 3
 
 	detectingErrMsg = "failed to detect iptables version. failed to run iptables-legacy-save, run iptables-nft-save, and get kernel version. NPM will crash to retry"
+
+	minNftKernelVersion = 5
 )
 
 var (
@@ -281,7 +283,7 @@ func (pMgr *PolicyManager) detectIptablesVersion() error {
 		return errDetectingIptablesVersion
 	}
 
-	if majorVersion >= 5 {
+	if majorVersion >= minNftKernelVersion {
 		msg := "detected iptables version on third attempt. found kernel version >= 5. NPM will use iptables-nft. kernel version: %d"
 		klog.Infof(msg, majorVersion)
 		metrics.SendLog(util.IptmID, fmt.Sprintf(msg, majorVersion), metrics.DonotPrint)
@@ -304,7 +306,7 @@ func (pMgr *PolicyManager) hintOrCanaryChainExist(iptablesCmd string) bool {
 		klog.Infof("failed to list hint chain. cmd: %s. error: %s", iptablesCmd, hintErr.Error())
 		metrics.SendErrorLogAndMetric(util.IptmID, "failed to list hint chain. cmd: %s. error: %s", iptablesCmd, hintErr.Error())
 	} else {
-		metrics.SendLog(util.IptmID, fmt.Sprintf("found hint chain. will use iptables version: %s", iptablesCmd), metrics.DonotPrint)
+		metrics.SendLog(util.IptmID, "found hint chain. will use iptables version: %s"+iptablesCmd, metrics.DonotPrint)
 		return true
 	}
 
@@ -317,7 +319,7 @@ func (pMgr *PolicyManager) hintOrCanaryChainExist(iptablesCmd string) bool {
 		return false
 	}
 
-	metrics.SendLog(util.IptmID, fmt.Sprintf("found canary chain. will use iptables version: %s", iptablesCmd), metrics.DonotPrint)
+	metrics.SendLog(util.IptmID, "found canary chain. will use iptables version: "+iptablesCmd, metrics.DonotPrint)
 	return true
 }
 
@@ -401,9 +403,9 @@ func (pMgr *PolicyManager) cleanupOtherIptables() error {
 
 	creator := pMgr.creatorForCleanup(chains)
 	if err := restore(creator); err != nil {
-		msg := fmt.Sprintf("[cleanup] failed to flush all chains with error: %s", err.Error())
-		klog.Info(msg)
-		metrics.SendErrorLogAndMetric(util.IptmID, msg)
+		msg := "[cleanup] failed to flush all chains with error: %s"
+		klog.Infof(msg, err.Error())
+		metrics.SendErrorLogAndMetric(util.IptmID, msg, err.Error())
 
 		// 3.2. if we failed to flush all chains, then try to flush and delete them one by one
 		var aggregateError error
@@ -432,7 +434,7 @@ func (pMgr *PolicyManager) cleanupOtherIptables() error {
 				if aggregateError == nil {
 					aggregateError = npmerrors.SimpleError(currentErrString)
 				} else {
-					aggregateError = npmerrors.SimpleErrorWrapper(fmt.Sprintf("%s and had previous error", currentErrString), aggregateError)
+					aggregateError = npmerrors.SimpleErrorWrapper(currentErrString+" and had previous error", aggregateError)
 				}
 			}
 		}
@@ -455,7 +457,7 @@ func (pMgr *PolicyManager) cleanupOtherIptables() error {
 			if aggregateError == nil {
 				aggregateError = npmerrors.SimpleError(currentErrString)
 			} else {
-				aggregateError = npmerrors.SimpleErrorWrapper(fmt.Sprintf("%s and had previous error", currentErrString), aggregateError)
+				aggregateError = npmerrors.SimpleErrorWrapper(currentErrString+" and had previous error", aggregateError)
 			}
 		}
 	}
@@ -473,7 +475,7 @@ func (pMgr *PolicyManager) creatorForCleanup(chains []string) *ioutil.FileCreato
 	// pass nil because we don't need to add any lines like ":CHAIN-NAME - -" because that is for creating chains
 	creator := pMgr.newCreatorWithChains(nil)
 	for _, chain := range chains {
-		creator.AddLine("", nil, fmt.Sprintf("-F %s", chain))
+		creator.AddLine("", nil, "-F "+chain)
 	}
 	creator.AddLine("", nil, util.IptablesRestoreCommit)
 	return creator

npm/pkg/dataplane/policies/chain-management_linux_test.go

@@ -44,6 +44,8 @@ Chain AZURE-NPM-INGRESS (1 references)
 `
 )
 
+var errKernelVersion = fmt.Errorf("kernel error")
+
 func TestStaleChainsForceLock(t *testing.T) {
 	testChains := []string{}
 	for i := 0; i < 100000; i++ {
@@ -1003,7 +1005,7 @@ func TestDetectIptablesVersion(t *testing.T) {
 		},
 		{
 			name:             "no kube chains: kernel version error",
-			kernelVersionErr: fmt.Errorf("kernel version error"),
+			kernelVersionErr: errKernelVersion,
 			calls: []testutils.TestCmd{
 				{
 					Cmd:      []string{"iptables-nft", "-w", "60", "-t", "mangle", "-n", "-L", "KUBE-IPTABLES-HINT"},

npm/pkg/dataplane/policies/policymanager.go

@@ -30,11 +30,11 @@ const (
 
 type PolicyManagerCfg struct {
 	// debug is only used for testing. Currently just indicating whether to use debug kernel version
-	debug bool
+	debug bool //nolint:unused // only used in linux
 	// debugKernelVersion is only used for testing
-	debugKernelVersion int
+	debugKernelVersion int //nolint:unused // only used in linux
 	// debugKernelVersionErr is only used for testing
-	debugKernelVersionErr error
+	debugKernelVersionErr error //nolint:unused // only used in linux
 
 	// NodeIP is only used in Windows
 	NodeIP string

npm/util/sysinfo_linux.go

@@ -3,6 +3,7 @@ package util
 // this file has bits copied from github.com/zcalusic/sysinfo (v1.1.2)
 
 import (
+	"errors"
 	"fmt"
 	"os"
 	"strconv"
@@ -11,7 +12,7 @@ import (
 
 const kernelReleaseFilepath = "/proc/sys/kernel/osrelease"
 
-var errNoKernelRelease = fmt.Errorf("error finding kernel release")
+var errNoKernelRelease = errors.New("error finding kernel release")
 
 func KernelReleaseMajorVersion() (int, error) {
 	rel, err := slurpFile(kernelReleaseFilepath)