cache_test.go

     1  // Copyright 2017 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package cache
     6  
     7  import (
     8  	"bytes"
     9  	"encoding/binary"
    10  	"fmt"
    11  	"internal/testenv"
    12  	"os"
    13  	"path/filepath"
    14  	"testing"
    15  	"time"
    16  )
    17  
    18  func init() {
    19  	verify = false // even if GODEBUG is set
    20  }
    21  
    22  func TestBasic(t *testing.T) {
    23  	dir := t.TempDir()
    24  	_, err := Open(filepath.Join(dir, "notexist"))
    25  	if err == nil {
    26  		t.Fatal(`Open("tmp/notexist") succeeded, want failure`)
    27  	}
    28  
    29  	cdir := filepath.Join(dir, "c1")
    30  	if err := os.Mkdir(cdir, 0777); err != nil {
    31  		t.Fatal(err)
    32  	}
    33  
    34  	c1, err := Open(cdir)
    35  	if err != nil {
    36  		t.Fatalf("Open(c1) (create): %v", err)
    37  	}
    38  	if err := c1.putIndexEntry(dummyID(1), dummyID(12), 13, true); err != nil {
    39  		t.Fatalf("addIndexEntry: %v", err)
    40  	}
    41  	if err := c1.putIndexEntry(dummyID(1), dummyID(2), 3, true); err != nil { // overwrite entry
    42  		t.Fatalf("addIndexEntry: %v", err)
    43  	}
    44  	if entry, err := c1.Get(dummyID(1)); err != nil || entry.OutputID != dummyID(2) || entry.Size != 3 {
    45  		t.Fatalf("c1.Get(1) = %x, %v, %v, want %x, %v, nil", entry.OutputID, entry.Size, err, dummyID(2), 3)
    46  	}
    47  
    48  	c2, err := Open(cdir)
    49  	if err != nil {
    50  		t.Fatalf("Open(c2) (reuse): %v", err)
    51  	}
    52  	if entry, err := c2.Get(dummyID(1)); err != nil || entry.OutputID != dummyID(2) || entry.Size != 3 {
    53  		t.Fatalf("c2.Get(1) = %x, %v, %v, want %x, %v, nil", entry.OutputID, entry.Size, err, dummyID(2), 3)
    54  	}
    55  	if err := c2.putIndexEntry(dummyID(2), dummyID(3), 4, true); err != nil {
    56  		t.Fatalf("addIndexEntry: %v", err)
    57  	}
    58  	if entry, err := c1.Get(dummyID(2)); err != nil || entry.OutputID != dummyID(3) || entry.Size != 4 {
    59  		t.Fatalf("c1.Get(2) = %x, %v, %v, want %x, %v, nil", entry.OutputID, entry.Size, err, dummyID(3), 4)
    60  	}
    61  }
    62  
    63  func TestGrowth(t *testing.T) {
    64  	c, err := Open(t.TempDir())
    65  	if err != nil {
    66  		t.Fatalf("Open: %v", err)
    67  	}
    68  
    69  	n := 10000
    70  	if testing.Short() {
    71  		n = 10
    72  	}
    73  
    74  	for i := 0; i < n; i++ {
    75  		if err := c.putIndexEntry(dummyID(i), dummyID(i*99), int64(i)*101, true); err != nil {
    76  			t.Fatalf("addIndexEntry: %v", err)
    77  		}
    78  		id := ActionID(dummyID(i))
    79  		entry, err := c.Get(id)
    80  		if err != nil {
    81  			t.Fatalf("Get(%x): %v", id, err)
    82  		}
    83  		if entry.OutputID != dummyID(i*99) || entry.Size != int64(i)*101 {
    84  			t.Errorf("Get(%x) = %x, %d, want %x, %d", id, entry.OutputID, entry.Size, dummyID(i*99), int64(i)*101)
    85  		}
    86  	}
    87  	for i := 0; i < n; i++ {
    88  		id := ActionID(dummyID(i))
    89  		entry, err := c.Get(id)
    90  		if err != nil {
    91  			t.Fatalf("Get2(%x): %v", id, err)
    92  		}
    93  		if entry.OutputID != dummyID(i*99) || entry.Size != int64(i)*101 {
    94  			t.Errorf("Get2(%x) = %x, %d, want %x, %d", id, entry.OutputID, entry.Size, dummyID(i*99), int64(i)*101)
    95  		}
    96  	}
    97  }
    98  
    99  func TestVerifyPanic(t *testing.T) {
   100  	os.Setenv("GODEBUG", "gocacheverify=1")
   101  	initEnv()
   102  	defer func() {
   103  		os.Unsetenv("GODEBUG")
   104  		verify = false
   105  	}()
   106  
   107  	if !verify {
   108  		t.Fatal("initEnv did not set verify")
   109  	}
   110  
   111  	c, err := Open(t.TempDir())
   112  	if err != nil {
   113  		t.Fatalf("Open: %v", err)
   114  	}
   115  
   116  	id := ActionID(dummyID(1))
   117  	if err := PutBytes(c, id, []byte("abc")); err != nil {
   118  		t.Fatal(err)
   119  	}
   120  
   121  	defer func() {
   122  		if err := recover(); err != nil {
   123  			t.Log(err)
   124  			return
   125  		}
   126  	}()
   127  	PutBytes(c, id, []byte("def"))
   128  	t.Fatal("mismatched Put did not panic in verify mode")
   129  }
   130  
   131  func dummyID(x int) [HashSize]byte {
   132  	var out [HashSize]byte
   133  	binary.LittleEndian.PutUint64(out[:], uint64(x))
   134  	return out
   135  }
   136  
   137  func TestCacheTrim(t *testing.T) {
   138  	dir := t.TempDir()
   139  	c, err := Open(dir)
   140  	if err != nil {
   141  		t.Fatalf("Open: %v", err)
   142  	}
   143  	const start = 1000000000
   144  	now := int64(start)
   145  	c.now = func() time.Time { return time.Unix(now, 0) }
   146  
   147  	checkTime := func(name string, mtime int64) {
   148  		t.Helper()
   149  		file := filepath.Join(c.dir, name[:2], name)
   150  		info, err := os.Stat(file)
   151  		if err != nil {
   152  			t.Fatal(err)
   153  		}
   154  		if info.ModTime().Unix() != mtime {
   155  			t.Fatalf("%s mtime = %d, want %d", name, info.ModTime().Unix(), mtime)
   156  		}
   157  	}
   158  
   159  	id := ActionID(dummyID(1))
   160  	PutBytes(c, id, []byte("abc"))
   161  	entry, _ := c.Get(id)
   162  	PutBytes(c, ActionID(dummyID(2)), []byte("def"))
   163  	mtime := now
   164  	checkTime(fmt.Sprintf("%x-a", id), mtime)
   165  	checkTime(fmt.Sprintf("%x-d", entry.OutputID), mtime)
   166  
   167  	// Get should not change recent mtimes.
   168  	now = start + 10
   169  	c.Get(id)
   170  	checkTime(fmt.Sprintf("%x-a", id), mtime)
   171  	checkTime(fmt.Sprintf("%x-d", entry.OutputID), mtime)
   172  
   173  	// Get should change distant mtimes.
   174  	now = start + 5000
   175  	mtime2 := now
   176  	if _, err := c.Get(id); err != nil {
   177  		t.Fatal(err)
   178  	}
   179  	c.OutputFile(entry.OutputID)
   180  	checkTime(fmt.Sprintf("%x-a", id), mtime2)
   181  	checkTime(fmt.Sprintf("%x-d", entry.OutputID), mtime2)
   182  
   183  	// Trim should leave everything alone: it's all too new.
   184  	if err := c.Trim(); err != nil {
   185  		if testenv.SyscallIsNotSupported(err) {
   186  			t.Skipf("skipping: Trim is unsupported (%v)", err)
   187  		}
   188  		t.Fatal(err)
   189  	}
   190  	if _, err := c.Get(id); err != nil {
   191  		t.Fatal(err)
   192  	}
   193  	c.OutputFile(entry.OutputID)
   194  	data, err := os.ReadFile(filepath.Join(dir, "trim.txt"))
   195  	if err != nil {
   196  		t.Fatal(err)
   197  	}
   198  	checkTime(fmt.Sprintf("%x-a", dummyID(2)), start)
   199  
   200  	// Trim less than a day later should not do any work at all.
   201  	now = start + 80000
   202  	if err := c.Trim(); err != nil {
   203  		t.Fatal(err)
   204  	}
   205  	if _, err := c.Get(id); err != nil {
   206  		t.Fatal(err)
   207  	}
   208  	c.OutputFile(entry.OutputID)
   209  	data2, err := os.ReadFile(filepath.Join(dir, "trim.txt"))
   210  	if err != nil {
   211  		t.Fatal(err)
   212  	}
   213  	if !bytes.Equal(data, data2) {
   214  		t.Fatalf("second trim did work: %q -> %q", data, data2)
   215  	}
   216  
   217  	// Fast forward and do another trim just before the 5 day cutoff.
   218  	// Note that because of usedQuantum the cutoff is actually 5 days + 1 hour.
   219  	// We used c.Get(id) just now, so 5 days later it should still be kept.
   220  	// On the other hand almost a full day has gone by since we wrote dummyID(2)
   221  	// and we haven't looked at it since, so 5 days later it should be gone.
   222  	now += 5 * 86400
   223  	checkTime(fmt.Sprintf("%x-a", dummyID(2)), start)
   224  	if err := c.Trim(); err != nil {
   225  		t.Fatal(err)
   226  	}
   227  	if _, err := c.Get(id); err != nil {
   228  		t.Fatal(err)
   229  	}
   230  	c.OutputFile(entry.OutputID)
   231  	mtime3 := now
   232  	if _, err := c.Get(dummyID(2)); err == nil { // haven't done a Get for this since original write above
   233  		t.Fatalf("Trim did not remove dummyID(2)")
   234  	}
   235  
   236  	// The c.Get(id) refreshed id's mtime again.
   237  	// Check that another 5 days later it is still not gone,
   238  	// but check by using checkTime, which doesn't bring mtime forward.
   239  	now += 5 * 86400
   240  	if err := c.Trim(); err != nil {
   241  		t.Fatal(err)
   242  	}
   243  	checkTime(fmt.Sprintf("%x-a", id), mtime3)
   244  	checkTime(fmt.Sprintf("%x-d", entry.OutputID), mtime3)
   245  
   246  	// Half a day later Trim should still be a no-op, because there was a Trim recently.
   247  	// Even though the entry for id is now old enough to be trimmed,
   248  	// it gets a reprieve until the time comes for a new Trim scan.
   249  	now += 86400 / 2
   250  	if err := c.Trim(); err != nil {
   251  		t.Fatal(err)
   252  	}
   253  	checkTime(fmt.Sprintf("%x-a", id), mtime3)
   254  	checkTime(fmt.Sprintf("%x-d", entry.OutputID), mtime3)
   255  
   256  	// Another half a day later, Trim should actually run, and it should remove id.
   257  	now += 86400/2 + 1
   258  	if err := c.Trim(); err != nil {
   259  		t.Fatal(err)
   260  	}
   261  	if _, err := c.Get(dummyID(1)); err == nil {
   262  		t.Fatal("Trim did not remove dummyID(1)")
   263  	}
   264  }
   265
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