github.com/m3db/m3@v1.5.0/src/dbnode/server/lockfile_test.go (about)

     1  // Copyright (c) 2018 Uber Technologies, Inc.
     2  //
     3  // Permission is hereby granted, free of charge, to any person obtaining a copy
     4  // of this software and associated documentation files (the "Software"), to deal
     5  // in the Software without restriction, including without limitation the rights
     6  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
     7  // copies of the Software, and to permit persons to whom the Software is
     8  // furnished to do so, subject to the following conditions:
     9  //
    10  // The above copyright notice and this permission notice shall be included in
    11  // all copies or substantial portions of the Software.
    12  //
    13  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    14  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    15  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    16  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    17  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    18  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    19  // THE SOFTWARE.
    20  
    21  package server
    22  
    23  import (
    24  	"fmt"
    25  	"io/ioutil"
    26  	"math/rand"
    27  	"os"
    28  	"os/exec"
    29  	"path"
    30  	"path/filepath"
    31  	"strconv"
    32  	"testing"
    33  	"time"
    34  
    35  	"github.com/stretchr/testify/assert"
    36  )
    37  
    38  func TestAcquire(t *testing.T) {
    39  	t.Run("process B can obtain the lock after A exits", func(t *testing.T) {
    40  		path := tempPath()
    41  		assert.NoError(t, newLockfileCommand(path, "", true).Run())
    42  		_, err := os.Stat(path)
    43  		assert.True(t, os.IsNotExist(err)) // check temp file was removed
    44  		assert.NoError(t, newLockfileCommand(path, "", true).Run())
    45  	})
    46  
    47  	t.Run("process B can obtain the lock after A exits, even if A didn't remove the lock file", func(t *testing.T) {
    48  		path := tempPath()
    49  		assert.NoError(t, newLockfileCommand(path, "", false).Run())
    50  		_, err := os.Stat(path)
    51  		assert.False(t, os.IsNotExist(err)) // check temp file was *not* removed
    52  		assert.NoError(t, newLockfileCommand(path, "", true).Run())
    53  	})
    54  
    55  	t.Run("if process A holds the lock, B must not be able to obtain it", func(t *testing.T) {
    56  		path := tempPath()
    57  
    58  		procA := newLockfileCommand(path, "1s", false)
    59  		procB := newLockfileCommand(path, "1s", false)
    60  
    61  		assert.NoError(t, procA.Start())
    62  		assert.NoError(t, procB.Start())
    63  
    64  		// one process will acquireLockfile and hold the lock, and the other will fail to acquireLockfile.
    65  		errA, errB := procA.Wait(), procB.Wait()
    66  
    67  		if errA != nil {
    68  			assert.NoError(t, errB)
    69  		} else {
    70  			assert.Error(t, errB)
    71  		}
    72  	})
    73  }
    74  
    75  func TestCreateAndAcquire(t *testing.T) {
    76  	tempDir, err := ioutil.TempDir("", "TestCreateAndAcquire")
    77  	assert.NoError(t, err)
    78  	defer os.RemoveAll(tempDir)
    79  
    80  	tempSubDir := path.Join(tempDir, "testDir")
    81  
    82  	lock, err := createAndAcquireLockfile(path.Join(tempSubDir, "testLockfile"), os.ModePerm)
    83  	assert.NoError(t, err)
    84  	err = lock.releaseLockfile()
    85  	assert.NoError(t, err)
    86  
    87  	// check createAndAcquireLockfile() created the missing directory
    88  	_, err = os.Stat(tempSubDir)
    89  	assert.False(t, os.IsNotExist(err))
    90  }
    91  
    92  // TestAcquireAndReleaseFile is invoked as a separate process by other tests in lockfile_test.go
    93  // to exercise the file locking capabilities. The test is a no-op if run as part
    94  // of the broader test suite. Given it's run as a separate process, we explicitly use error
    95  // exit codes as opposed to failing assertions on errors
    96  func TestAcquireAndReleaseFile(t *testing.T) {
    97  	// immediately return if this test wasn't invoked by another test in the
    98  	// nolint: goconst
    99  	if os.Getenv("LOCKFILE_SUPERVISED_PROCESS") != "true" {
   100  		t.Skip()
   101  	}
   102  
   103  	var (
   104  		lockPath      = os.Getenv("WITH_LOCK_PATH")
   105  		removeLock    = os.Getenv("WITH_REMOVE_LOCK")
   106  		sleepDuration = os.Getenv("WITH_SLEEP_DURATION")
   107  	)
   108  
   109  	lock, err := acquireLockfile(lockPath)
   110  	if err != nil {
   111  		os.Exit(1)
   112  	}
   113  
   114  	if sleepDuration != "" {
   115  		duration, err := time.ParseDuration(sleepDuration)
   116  		if err != nil {
   117  			os.Exit(1)
   118  		}
   119  
   120  		time.Sleep(duration)
   121  	}
   122  
   123  	if removeLock == "true" {
   124  		err := lock.releaseLockfile()
   125  		if err != nil {
   126  			os.Exit(1)
   127  		}
   128  	}
   129  }
   130  
   131  func tempPath() string {
   132  	return filepath.Join(os.TempDir(), "lockfile_test_"+strconv.Itoa(os.Getpid())+"_"+strconv.Itoa(rand.Intn(100000)))
   133  }
   134  
   135  func newLockfileCommand(lockPath string, sleepDuration string, removeLock bool) *exec.Cmd {
   136  	removeLockStr := "false"
   137  	if removeLock {
   138  		removeLockStr = "true"
   139  	}
   140  
   141  	cmd := exec.Command("go", "test", "-run", "TestAcquireAndReleaseFile")
   142  	cmd.Env = os.Environ()
   143  	cmd.Env = append(
   144  		cmd.Env,
   145  		"LOCKFILE_SUPERVISED_PROCESS=true",
   146  		fmt.Sprintf("WITH_LOCK_PATH=%s", lockPath),
   147  		fmt.Sprintf("WITH_SLEEP_DURATION=%s", sleepDuration),
   148  		fmt.Sprintf("WITH_REMOVE_LOCK=%s", removeLockStr),
   149  	)
   150  
   151  	return cmd
   152  }