Add errcheck to test suite to ensure all errors produced are checked

build/test.sh

@@ -50,3 +50,16 @@ if [ -n "${ERRS}" ]; then
 fi
 echo "PASS"
 echo
+
+echo -n "Checking errcheck: "
+go install github.com/kisielk/errcheck@latest 2>/dev/null
+ERRS=$(errcheck -exclude errcheck_excludes.txt -ignoretests ${TARGETS} 2>&1 || true)
+if [ -n "${ERRS}" ]; then
+    echo "FAIL"
+    echo "${ERRS}"
+    echo
+    exit 1
+fi
+echo "PASS"
+echo
+

cmd/echo/app/handlers.go

@@ -136,7 +136,9 @@ func process(w http.ResponseWriter, r *http.Request, b []byte) ([]byte, error) {
 		if err != nil {
 			return nil, fmt.Errorf("failed to compress data: %v", err)
 		}
-		zw.Close()
+		if err := zw.Close(); err != nil {
+			return nil, fmt.Errorf("failed to close gzip writer: %v", err)
+		}
 		w.Header().Set("Content-Encoding", "gzip")
 		return compressed.Bytes(), nil
 	}

cmd/echo/app/tls.go

@@ -93,11 +93,15 @@ func generateInsecureCertAndKey(organization string, validFrom time.Time, validF
 		klog.Fatalf("Failed to create certificate: %s", err)
 	}
 	var certBytes bytes.Buffer
-	pem.Encode(&certBytes, &pem.Block{Type: "CERTIFICATE", Bytes: derBytes})
+	if err := pem.Encode(&certBytes, &pem.Block{Type: "CERTIFICATE", Bytes: derBytes}); err != nil {
+		klog.Fatalf("Failed to encode certificate: %v", err)
+	}
 
 	var keyBytes bytes.Buffer
 	pb := &pem.Block{Type: "RSA PRIVATE KEY", Bytes: x509.MarshalPKCS1PrivateKey(priv)}
-	pem.Encode(&keyBytes, pb)
+	if err := pem.Encode(&keyBytes, pb); err != nil {
+		klog.Fatalf("Failed to encode RSA Key: %v", err)
+	}
 
 	return certBytes.Bytes(), keyBytes.Bytes(), nil
 }

cmd/glbc/app/handlers.go

@@ -141,7 +141,9 @@ func getFlagPage(w http.ResponseWriter, r *http.Request) {
 		Version:   version.Version,
 		Verbosity: flag.Lookup("v").Value.String(),
 	}
-	flagPageTemplate.Execute(w, s)
+	if err := flagPageTemplate.Execute(w, s); err != nil {
+		klog.Errorf("Unable to apply flag page template: %v", err)
+	}
 }
 
 var flagPageTemplate = template.Must(template.New("").Parse(`GCE Ingress Controller "GLBC"

cmd/glbc/main.go

@@ -270,7 +270,10 @@ func runControllers(ctx *ingctx.ControllerContext) {
 	lbc := controller.NewLoadBalancerController(ctx, stopCh)
 	if ctx.EnableASMConfigMap {
 		ctx.ASMConfigController.RegisterInformer(ctx.ConfigMapInformer, func() {
-			lbc.Stop(false) // We want to trigger a restart, don't have to clean up all the resources.
+			// We want to trigger a restart, don't have to clean up all the resources.
+			if err := lbc.Stop(false); err != nil {
+				klog.Errorf("Failed to stop the load balancer controller: %v", err)
+			}
 		})
 	}
 

errcheck_excludes.txt

@@ -0,0 +1,11 @@
+fmt.Fprintf
+fmt.Fprint
+(net/http.ResponseWriter).Write
+(*net/http.Server).Shutdown
+(*flag.FlagSet).Parse
+(*os.File).Close
+(io.Closer).Close
+(flag.Value).Set
+
+// We sometimes call this with a function that has no chance to error
+k8s.io/apimachinery/pkg/util/wait.PollUntil

pkg/composite/meta/meta.go

@@ -221,7 +221,9 @@ func populateApiServices() {
 	}
 
 	var result map[string]interface{}
-	json.Unmarshal([]byte(byteValue), &result)
+	if err := json.Unmarshal([]byte(byteValue), &result); err != nil {
+		panic(err)
+	}
 
 	// Queue of ApiService names for BFS
 	typesQueue := []string{}

pkg/e2e/helpers.go

@@ -101,7 +101,9 @@ var Scheme = runtime.NewScheme()
 
 func init() {
 	// Register external types for Scheme
-	v1.AddToScheme(Scheme)
+	if err := v1.AddToScheme(Scheme); err != nil {
+		panic(err)
+	}
 }
 
 // IsRfc1918Addr returns true if the address supplied is an RFC1918 address

pkg/firewalls/controller.go

@@ -158,7 +158,9 @@ func (fwc *FirewallController) sync(key string) error {
 
 	// If there are no more ingresses, then delete the firewall rule.
 	if len(gceIngresses) == 0 {
-		fwc.firewallPool.GC()
+		if err := fwc.firewallPool.GC(); err != nil {
+			klog.Errorf("Could not garbage collect firewall pool, got error: %v", err)
+		}
 		return nil
 	}
 

pkg/loadbalancers/address_manager.go

@@ -254,7 +254,9 @@ func (am *addressManager) TearDownAddressIPIfNetworkTierMismatch() error {
 			return utils.NewNetworkTierErr(fmt.Sprintf("User specific address IP (%v)", am.name), string(am.networkTier), addr.NetworkTier)
 		}
 		klog.V(3).Infof("Deleting IP address %v because has wrong network tier", am.targetIP)
-		am.svc.DeleteRegionAddress(addr.Name, am.targetIP)
+		if err := am.svc.DeleteRegionAddress(addr.Name, am.targetIP); err != nil {
+			klog.Errorf("Unable to delete region address %s on target ip %s, err: %v", addr.Name, am.targetIP, err)
+		}
 	}
 	return nil
 }