util: add helper ExecCommandWithTimeout function

added ExecCommandWithTimeout helper function
to execute the commands with the timeout option,
if the command does not return any response with
in the timeout time the process will be terminated
and error will be returned back to the user.

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

internal/util/cephcmds.go

@@ -22,6 +22,7 @@ import (
 	"errors"
 	"fmt"
 	"os/exec"
+	"time"
 
 	"github.com/ceph/ceph-csi/internal/util/log"
 
@@ -65,6 +66,59 @@ func ExecCommand(ctx context.Context, program string, args ...string) (string, s
 	return stdout, stderr, nil
 }
 
+// ExecCommandWithTimeout executes passed in program with args, timeout and
+// returns separate stdout and stderr streams. If the command is not executed
+// within given timeout, the process will be killed. In case ctx is not set to
+// context.TODO(), the command will be logged after it was executed.
+func ExecCommandWithTimeout(
+	ctx context.Context,
+	timeout time.Duration,
+	program string,
+	args ...string) (
+	string,
+	string,
+	error) {
+	var (
+		sanitizedArgs = StripSecretInArgs(args)
+		stdoutBuf     bytes.Buffer
+		stderrBuf     bytes.Buffer
+	)
+
+	cctx, cancel := context.WithTimeout(context.Background(), timeout)
+	defer cancel()
+
+	cmd := exec.CommandContext(cctx, program, args...) // #nosec:G204, commands executing not vulnerable.
+	cmd.Stdout = &stdoutBuf
+	cmd.Stderr = &stderrBuf
+
+	err := cmd.Run()
+	stdout := stdoutBuf.String()
+	stderr := stderrBuf.String()
+	if err != nil {
+		// if its a timeout log return context deadline exceeded error message
+		if errors.Is(cctx.Err(), context.DeadlineExceeded) {
+			err = fmt.Errorf("timeout: %w", cctx.Err())
+		}
+		err = fmt.Errorf("an error (%w) and stderror (%s) occurred while running %s args: %v",
+			err,
+			stderr,
+			program,
+			sanitizedArgs)
+
+		if ctx != context.TODO() {
+			log.ErrorLog(ctx, "%s", err)
+		}
+
+		return stdout, stderr, err
+	}
+
+	if ctx != context.TODO() {
+		log.UsefulLog(ctx, "command succeeded: %s %v", program, sanitizedArgs)
+	}
+
+	return stdout, stderr, nil
+}
+
 // GetPoolID fetches the ID of the pool that matches the passed in poolName
 // parameter.
 func GetPoolID(monitors string, cr *Credentials, poolName string) (int64, error) {

internal/util/cephcmds_test.go

@@ -0,0 +1,89 @@
+/*
+Copyright 2021 The Ceph-CSI 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 util
+
+import (
+	"context"
+	"errors"
+	"testing"
+	"time"
+)
+
+func TestExecCommandWithTimeout(t *testing.T) {
+	t.Parallel()
+	type args struct {
+		ctx     context.Context
+		program string
+		timeout time.Duration
+		args    []string
+	}
+	tests := []struct {
+		name        string
+		args        args
+		stdout      string
+		expectedErr error
+		wantErr     bool
+	}{
+		{
+			name: "echo hello",
+			args: args{
+				ctx:     context.TODO(),
+				program: "echo",
+				timeout: time.Second,
+				args:    []string{"hello"},
+			},
+			stdout:      "hello\n",
+			expectedErr: nil,
+			wantErr:     false,
+		},
+		{
+			name: "sleep with timeout",
+			args: args{
+				ctx:     context.TODO(),
+				program: "sleep",
+				timeout: time.Second,
+				args:    []string{"3"},
+			},
+			stdout:      "",
+			expectedErr: context.DeadlineExceeded,
+			wantErr:     true,
+		},
+	}
+	for _, tt := range tests {
+		newtt := tt
+		t.Run(newtt.name, func(t *testing.T) {
+			t.Parallel()
+			stdout, _, err := ExecCommandWithTimeout(newtt.args.ctx,
+				newtt.args.timeout,
+				newtt.args.program,
+				newtt.args.args...)
+			if (err != nil) != newtt.wantErr {
+				t.Errorf("ExecCommandWithTimeout() error = %v, wantErr %v", err, newtt.wantErr)
+
+				return
+			}
+
+			if newtt.wantErr && !errors.Is(err, newtt.expectedErr) {
+				t.Errorf("ExecCommandWithTimeout() error expected got = %v, want %v", err, newtt.expectedErr)
+			}
+
+			if stdout != newtt.stdout {
+				t.Errorf("ExecCommandWithTimeout() got = %v, want %v", stdout, newtt.stdout)
+			}
+		})
+	}
+}