mirrors/dnscrypt-proxy
1
0
Fork 0
mirror of https://github.com/DNSCrypt/dnscrypt-proxy.git synced 2025-04-06 06:37:36 +03:00
Code Issues Projects Releases Packages Wiki Activity

Fix prefetch sometimes being skipped

Browse source 
Previously when the cache was written to disk, the modification time was unspecified.
At the next prefetch, it was possible for the cache to be expiring very soon (on the order of milliseconds) but still deemed valid.
Now the modification time is explicitly set to when the prefetch run began to make this situation much less likely.
This commit is contained in:
William Elwood 2019-11-10 10:52:42 +00:00 • committed by Frank Denis
parent 96ffc778af
commit d43fcabe69
2 changed files with 36 additions and 17 deletions
Download patch file Download diff file Expand all files Collapse all files

44
dnscrypt-proxy/sources_test.go
View file

@ -60,6 +60,7 @@ type SourceTestExpect struct {
success bool
err, cachePath string
cache []SourceFixture
mtime time.Time
urls []string
Source *Source
delay time.Duration
@ -73,12 +74,12 @@ func readFixture(t *testing.T, name string) []byte {
return bin
}
func writeSourceCache(t *testing.T, basePath string, fixtures []SourceFixture) {
for _, f := range fixtures {
func writeSourceCache(t *testing.T, e *SourceTestExpect) {
for _, f := range e.cache {
if f.content == nil {
continue
}
path := basePath + f.suffix
path := e.cachePath + f.suffix
perms := f.perms
if perms == 0 {
perms = 0644
@ -89,21 +90,35 @@ func writeSourceCache(t *testing.T, basePath string, fixtures []SourceFixture) {
if err := acl.Chmod(path, perms); err != nil {
t.Fatalf("Unable to set permissions on cache file %s: %v", path, err)
}
if f.mtime.IsZero() {
if f.suffix != "" {
continue
}
if err := os.Chtimes(path, f.mtime, f.mtime); err != nil {
mtime := f.mtime
if f.mtime.IsZero() {
mtime = e.mtime
}
if err := os.Chtimes(path, mtime, mtime); err != nil {
t.Fatalf("Unable to touch cache file %s to %v: %v", path, f.mtime, err)
}
}
}
func checkSourceCache(c *check.C, basePath string, fixtures []SourceFixture) {
for _, f := range fixtures {
path := basePath + f.suffix
func checkSourceCache(c *check.C, e *SourceTestExpect) {
for _, f := range e.cache {
path := e.cachePath + f.suffix
_ = acl.Chmod(path, 0644) // don't worry if this fails, reading it will catch the same problem
got, err := ioutil.ReadFile(path)
c.DeepEqual(got, f.content, "Cache file '%s', err %v", path, err)
c.DeepEqual(got, f.content, "Unexpected content for cache file '%s', err %v", path, err)
if f.suffix != "" {
continue
}
if fi, err := os.Stat(path); err == nil { // again, if this failed it was already caught above
mtime := f.mtime
if f.mtime.IsZero() {
mtime = e.mtime
}
c.EQ(fi.ModTime(), mtime, "Unexpected timestamp for cache file '%s'", path)
}
}
}
@ -139,7 +154,7 @@ func generateFixtureState(t *testing.T, d *SourceTestData, suffix, file string,
return
}
}
f := SourceFixture{suffix: suffix, mtime: d.timeNow}
f := SourceFixture{suffix: suffix}
switch state {
case TestStateExpired:
f.content, f.mtime = d.fixtures[TestStateCorrect][file].content, d.timeOld
@ -161,7 +176,6 @@ func loadFixtures(t *testing.T, d *SourceTestData) {
d.fixtures[TestStateCorrect][file] = SourceFixture{
suffix: suffix,
content: readFixture(t, filepath.Join("sources", file)),
mtime: d.timeNow,
}
for _, state := range [...]SourceTestState{
TestStateExpired,
@ -277,7 +291,7 @@ func prepSourceTestCache(t *testing.T, d *SourceTestData, e *SourceTestExpect, s
case TestStateMissing, TestStateMissingSig, TestStateOpenErr, TestStateOpenSigErr:
e.err = "open"
}
writeSourceCache(t, e.cachePath, e.cache)
writeSourceCache(t, e)
}
func prepSourceTestDownload(t *testing.T, d *SourceTestData, e *SourceTestExpect, source string, downloadTest []SourceTestState) {
@ -336,6 +350,7 @@ func setupSourceTestCase(t *testing.T, d *SourceTestData, i int,
id = strconv.Itoa(d.n) + "-" + strconv.Itoa(i)
e = &SourceTestExpect{
cachePath: filepath.Join(d.tempDir, id),
mtime: d.timeNow,
}
e.Source = &Source{name: id, urls: []*url.URL{}, format: SourceFormatV2, minisignKey: d.key,
cacheFile: e.cachePath, cacheTTL: DefaultPrefetchDelay * 3, prefetchDelay: DefaultPrefetchDelay}
@ -359,7 +374,7 @@ func TestNewSource(t *testing.T) {
}
c.DeepEqual(got, e.Source, "Unexpected return")
checkTestServer(c, d)
checkSourceCache(c, e.cachePath, e.cache)
checkSourceCache(c, e)
}
d.n++
for _, tt := range []struct {
@ -402,7 +417,7 @@ func TestPrefetchSources(t *testing.T) {
c.InDelta(got, expectDelay, time.Second, "Unexpected return")
checkTestServer(c, d)
for _, e := range expects {
checkSourceCache(c, e.cachePath, e.cache)
checkSourceCache(c, e)
}
}
timeNow = func() time.Time { return d.timeUpd } // since the fixtures are prepared using real now, make the tested code think it's the future
@ -412,6 +427,7 @@ func TestPrefetchSources(t *testing.T) {
expects := []*SourceTestExpect{}
for i := range d.sources {
_, e := setupSourceTestCase(t, d, i, nil, downloadTest)
e.mtime = d.timeUpd
sources = append(sources, e.Source)
expects = append(expects, e)
}