e2e: add isAlreadyExistsCLIError to check known error

added isAlreadyExistsCLIError to check for known error.
if error is already exists we are considering it
as a success.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>

e2e/errors.go

@@ -43,3 +43,71 @@ func isRetryableAPIError(err error) bool {
 
 	return false
 }
+
+//nolint:lll // sample output cannot be split into multiple lines.
+/*
+getStdErr will extract the stderror and returns the actual error message
+
+Sample kubectl output:
+
+error running /usr/local/bin/kubectl --server=https://192.168.39.67:8443 --kubeconfig=***** --namespace=default create -f -:
+Command stdout:
+
+stderr:
+Error from server (AlreadyExists): error when creating "STDIN": services "csi-rbdplugin-provisioner" already exists
+Error from server (AlreadyExists): error when creating "STDIN": deployments.apps "csi-rbdplugin-provisioner" already exists
+
+error:
+exit status 1
+
+Sample message returned from this function:
+
+Error from server (AlreadyExists): error when creating "STDIN": services "csi-rbdplugin-provisioner" already exists
+Error from server (AlreadyExists): error when creating "STDIN": deployments.apps "csi-rbdplugin-provisioner" already exists.
+*/
+func getStdErr(errString string) string {
+	stdErrStr := "stderr:\n"
+	errStr := "error:\n"
+	stdErrPosition := strings.Index(errString, stdErrStr)
+	if stdErrPosition == -1 {
+		return ""
+	}
+
+	errPosition := strings.Index(errString, errStr)
+	if errPosition == -1 {
+		return ""
+	}
+
+	stdErrPositionLength := stdErrPosition + len(stdErrStr)
+	if stdErrPositionLength >= errPosition {
+		return ""
+	}
+
+	return errString[stdErrPosition+len(stdErrStr) : errPosition]
+}
+
+// isAlreadyExistsCLIError checks for already exists error from kubectl CLI.
+func isAlreadyExistsCLIError(err error) bool {
+	if err == nil {
+		return false
+	}
+	// if multiple resources already exists. each error is separated by newline
+	stdErr := getStdErr(err.Error())
+	if stdErr == "" {
+		return false
+	}
+
+	stdErrs := strings.Split(stdErr, "\n")
+	for _, s := range stdErrs {
+		// If the string is just a new line continue
+		if strings.TrimSuffix(s, "\n") == "" {
+			continue
+		}
+		// Resource already exists error message
+		if !strings.Contains(s, "Error from server (AlreadyExists)") {
+			return false
+		}
+	}
+
+	return true
+}

e2e/errors_test.go

@@ -0,0 +1,89 @@
+/*
+Copyright 2020 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package e2e
+
+import (
+	"fmt"
+	"testing"
+)
+
+// nolint:lll // error string cannot be split into multiple lines as is a
+// output from kubectl.
+func TestGetStdErr(t *testing.T) {
+	t.Parallel()
+	tests := []struct {
+		name                string
+		errString           string
+		expected            string
+		isAlreadyExistError bool
+	}{
+		{
+			name: "stdErr output when error is found",
+			errString: `
+error running /usr/local/bin/kubectl --server=https://192.168.39.67:8443 --kubeconfig=***** --namespace=default create -f -:
+Command stdout:
+
+stderr:
+Error from server (AlreadyExists): error when creating "STDIN": services "csi-rbdplugin-provisioner" already exists
+Error from server (AlreadyExists): error when creating "STDIN": deployments.apps "csi-rbdplugin-provisioner" already exists
+
+error:
+exit status 1`,
+			expected: `Error from server (AlreadyExists): error when creating "STDIN": services "csi-rbdplugin-provisioner" already exists
+Error from server (AlreadyExists): error when creating "STDIN": deployments.apps "csi-rbdplugin-provisioner" already exists
+
+`,
+			isAlreadyExistError: true,
+		},
+		{
+			name: "stdErr output when stderr: string is not found",
+			errString: `
+error running /usr/local/bin/kubectl --server=https://192.168.39.67:8443 --kubeconfig=***** --namespace=default create -f -:
+Command stdout:
+
+error:
+exit status 1`,
+			expected:            "",
+			isAlreadyExistError: false,
+		},
+		{
+			name: "stdErr output when error: string is not found",
+			errString: `
+error running /usr/local/bin/kubectl --server=https://192.168.39.67:8443 --kubeconfig=***** --namespace=default create -f -:
+Command stdout:
+
+stderr:
+Error from server (AlreadyExists): error when creating "STDIN": services "csi-rbdplugin-provisioner" already exists
+Error from server (AlreadyExists): error when creating "STDIN": deployments.apps "csi-rbdplugin-provisioner" already exists`,
+			expected:            "",
+			isAlreadyExistError: false,
+		},
+	}
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+			if got := getStdErr(tt.errString); got != tt.expected {
+				t.Errorf("getStdErr() output = %v, expected %v", got, tt.expected)
+			}
+
+			if got := isAlreadyExistsCLIError(fmt.Errorf("%s", tt.errString)); got != tt.isAlreadyExistError {
+				t.Errorf("isAlreadyExistsCLIError() output = %v, expected %v", got, tt.isAlreadyExistError)
+			}
+		})
+	}
+}

e2e/utils.go

@@ -1252,6 +1252,9 @@ func retryKubectlInput(namespace string, action kubectlAction, data string, t in
 			if isRetryableAPIError(err) {
 				return false, nil
 			}
+			if isAlreadyExistsCLIError(err) {
+				return true, nil
+			}
 			e2elog.Logf(
 				"will run kubectl (%s) again (%d seconds elapsed)",
 				action,
@@ -1278,6 +1281,9 @@ func retryKubectlFile(namespace string, action kubectlAction, filename string, t
 			if isRetryableAPIError(err) {
 				return false, nil
 			}
+			if isAlreadyExistsCLIError(err) {
+				return true, nil
+			}
 			e2elog.Logf(
 				"will run kubectl (%s -f %q) again (%d seconds elapsed)",
 				action,