Add dugong to support writing to disk/rotations

5 files changed, 741 insertions, 0 deletions

diff --git a/vendor/manifest b/vendor/manifest
index 2d503c3e..a271175c 100644
--- a/vendor/manifest
+++ b/vendor/manifest
@@ -78,6 +78,12 @@
 			"branch": "master"
 		},
 		{
+			"importpath": "github.com/matrix-org/dugong",
+			"repository": "https://github.com/matrix-org/dugong",
+			"revision": "193b8f88e381d12f2d53023fba25e43fc81dc5ac",
+			"branch": "master"
+		},
+		{
 			"importpath": "github.com/matrix-org/gomatrixserverlib",
 			"repository": "https://github.com/matrix-org/gomatrixserverlib",
 			"revision": "48ee56a33d195dc412dd919a0e81af70c9aaf4a3",
diff --git a/vendor/src/github.com/matrix-org/dugong/LICENSE b/vendor/src/github.com/matrix-org/dugong/LICENSE
new file mode 100644
index 00000000..8dada3ed
--- /dev/null
+++ b/vendor/src/github.com/matrix-org/dugong/LICENSE
@@ -0,0 +1,201 @@
+                                 Apache License
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+
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diff --git a/vendor/src/github.com/matrix-org/dugong/README.md b/vendor/src/github.com/matrix-org/dugong/README.md
new file mode 100644
index 00000000..cc226765
--- /dev/null
+++ b/vendor/src/github.com/matrix-org/dugong/README.md
@@ -0,0 +1,10 @@
+# dugong
+Logging utilities for [logrus](https://github.com/Sirupsen/logrus).
+
+To develop on this library, you need logrus on your GOPATH:
+
+  ``go get github.com/Sirupsen/logrus``
+  
+You can then run its tests by running
+
+  ``go test``
diff --git a/vendor/src/github.com/matrix-org/dugong/fshook.go b/vendor/src/github.com/matrix-org/dugong/fshook.go
new file mode 100644
index 00000000..be539ab4
--- /dev/null
+++ b/vendor/src/github.com/matrix-org/dugong/fshook.go
@@ -0,0 +1,210 @@
+package dugong
+
+import (
+	"compress/gzip"
+	"fmt"
+	log "github.com/Sirupsen/logrus"
+	"io"
+	"os"
+	"path/filepath"
+	"sync/atomic"
+	"time"
+)
+
+// RotationScheduler determines when files should be rotated.
+type RotationScheduler interface {
+	// ShouldRotate returns true if the file should be rotated. The suffix to apply
+	// to the filename is returned as the 2nd arg.
+	ShouldRotate() (bool, string)
+	// ShouldGZip returns true if the file should be gzipped when it is rotated.
+	ShouldGZip() bool
+}
+
+// DailyRotationSchedule rotates log files daily. Logs are only rotated
+// when midnight passes *whilst the process is running*. E.g: if you run
+// the process on Day 4 then stop it and start it on Day 7, no rotation will
+// occur when the process starts.
+type DailyRotationSchedule struct {
+	GZip        bool
+	rotateAfter *time.Time
+}
+
+var currentTime = time.Now // exclusively for testing
+
+func dayOffset(t time.Time, offsetDays int) time.Time {
+	// GoDoc:
+	//   The month, day, hour, min, sec, and nsec values may be outside their
+	//   usual ranges and will be normalized during the conversion.
+	//   For example, October 32 converts to November 1.
+	return time.Date(
+		t.Year(), t.Month(), t.Day()+offsetDays, 0, 0, 0, 0, t.Location(),
+	)
+}
+
+func (rs *DailyRotationSchedule) ShouldRotate() (bool, string) {
+	now := currentTime()
+	if rs.rotateAfter == nil {
+		nextRotate := dayOffset(now, 1)
+		rs.rotateAfter = &nextRotate
+		return false, ""
+	}
+	if now.After(*rs.rotateAfter) {
+		// the suffix should be actually the date of the complete day being logged
+		actualDay := dayOffset(*rs.rotateAfter, -1)
+		suffix := "." + actualDay.Format("2006-01-02") // YYYY-MM-DD
+		nextRotate := dayOffset(now, 1)
+		rs.rotateAfter = &nextRotate
+		return true, suffix
+	}
+	return false, ""
+}
+
+func (rs *DailyRotationSchedule) ShouldGZip() bool {
+	return rs.GZip
+}
+
+// NewFSHook makes a logging hook that writes formatted
+// log entries to info, warn and error log files. Each log file
+// contains the messages with that severity or higher. If a formatter is
+// not specified, they will be logged using a JSON formatter. If a
+// RotationScheduler is set, the files will be cycled according to its rules.
+func NewFSHook(infoPath, warnPath, errorPath string, formatter log.Formatter, rotSched RotationScheduler) log.Hook {
+	if formatter == nil {
+		formatter = &log.JSONFormatter{}
+	}
+	hook := &fsHook{
+		entries:   make(chan log.Entry, 1024),
+		infoPath:  infoPath,
+		warnPath:  warnPath,
+		errorPath: errorPath,
+		formatter: formatter,
+		scheduler: rotSched,
+	}
+
+	go func() {
+		for entry := range hook.entries {
+			if err := hook.writeEntry(&entry); err != nil {
+				fmt.Fprintf(os.Stderr, "Error writing to logfile: %v\n", err)
+			}
+			atomic.AddInt32(&hook.queueSize, -1)
+		}
+	}()
+
+	return hook
+}
+
+type fsHook struct {
+	entries   chan log.Entry
+	queueSize int32
+	infoPath  string
+	warnPath  string
+	errorPath string
+	formatter log.Formatter
+	scheduler RotationScheduler
+}
+
+func (hook *fsHook) Fire(entry *log.Entry) error {
+	atomic.AddInt32(&hook.queueSize, 1)
+	hook.entries <- *entry
+	return nil
+}
+
+func (hook *fsHook) writeEntry(entry *log.Entry) error {
+	msg, err := hook.formatter.Format(entry)
+	if err != nil {
+		return nil
+	}
+
+	if hook.scheduler != nil {
+		if should, suffix := hook.scheduler.ShouldRotate(); should {
+			if err := hook.rotate(suffix, hook.scheduler.ShouldGZip()); err != nil {
+				return err
+			}
+		}
+	}
+
+	if entry.Level <= log.ErrorLevel {
+		if err := logToFile(hook.errorPath, msg); err != nil {
+			return err
+		}
+	}
+
+	if entry.Level <= log.WarnLevel {
+		if err := logToFile(hook.warnPath, msg); err != nil {
+			return err
+		}
+	}
+
+	if entry.Level <= log.InfoLevel {
+		if err := logToFile(hook.infoPath, msg); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (hook *fsHook) Levels() []log.Level {
+	return []log.Level{
+		log.PanicLevel,
+		log.FatalLevel,
+		log.ErrorLevel,
+		log.WarnLevel,
+		log.InfoLevel,
+	}
+}
+
+// rotate all the log files to the given suffix.
+// If error path is "err.log" and suffix is "1" then move
+// the contents to "err.log1".
+// This requires no locking as the goroutine calling this is the same
+// one which does the logging. Since we don't hold open a handle to the
+// file when writing, a simple Rename is all that is required.
+func (hook *fsHook) rotate(suffix string, gzip bool) error {
+	for _, fpath := range []string{hook.errorPath, hook.warnPath, hook.infoPath} {
+		logFilePath := fpath + suffix
+		if err := os.Rename(fpath, logFilePath); err != nil {
+			// e.g. because there were no errors in error.log for this day
+			fmt.Fprintf(os.Stderr, "Error rotating file %s: %v\n", fpath, err)
+			continue // don't try to gzip if we failed to rotate
+		}
+		if gzip {
+			if err := gzipFile(logFilePath); err != nil {
+				fmt.Fprintf(os.Stderr, "Failed to gzip file %s: %v\n", logFilePath, err)
+			}
+		}
+	}
+	return nil
+}
+
+func logToFile(path string, msg []byte) error {
+	fd, err := os.OpenFile(path, os.O_WRONLY|os.O_APPEND|os.O_CREATE, 0600)
+	if err != nil {
+		return err
+	}
+	defer fd.Close()
+	_, err = fd.Write(msg)
+	return err
+}
+
+func gzipFile(fpath string) error {
+	reader, err := os.Open(fpath)
+	if err != nil {
+		return err
+	}
+
+	filename := filepath.Base(fpath)
+	target := filepath.Join(filepath.Dir(fpath), filename+".gz")
+	writer, err := os.Create(target)
+	if err != nil {
+		return err
+	}
+	defer writer.Close()
+
+	archiver := gzip.NewWriter(writer)
+	archiver.Name = filename
+	defer archiver.Close()
+
+	_, err = io.Copy(archiver, reader)
+	return err
+}
diff --git a/vendor/src/github.com/matrix-org/dugong/fshook_test.go b/vendor/src/github.com/matrix-org/dugong/fshook_test.go
new file mode 100644
index 00000000..a51a51fe
--- /dev/null
+++ b/vendor/src/github.com/matrix-org/dugong/fshook_test.go
@@ -0,0 +1,314 @@
+package dugong
+
+import (
+	"bufio"
+	"encoding/json"
+	log "github.com/Sirupsen/logrus"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"runtime"
+	"sync"
+	"sync/atomic"
+	"testing"
+	"time"
+)
+
+const (
+	fieldName  = "my_field"
+	fieldValue = "my_value"
+)
+
+func TestFSHookInfo(t *testing.T) {
+	logger, hook, wait, teardown := setupLogHook(t)
+	defer teardown()
+
+	logger.WithField(fieldName, fieldValue).Info("Info message")
+
+	wait()
+
+	checkLogFile(t, hook.infoPath, "info")
+}
+
+func TestFSHookWarn(t *testing.T) {
+	logger, hook, wait, teardown := setupLogHook(t)
+	defer teardown()
+
+	logger.WithField(fieldName, fieldValue).Warn("Warn message")
+
+	wait()
+
+	checkLogFile(t, hook.infoPath, "warning")
+	checkLogFile(t, hook.warnPath, "warning")
+}
+
+func TestFSHookError(t *testing.T) {
+	logger, hook, wait, teardown := setupLogHook(t)
+	defer teardown()
+
+	logger.WithField(fieldName, fieldValue).Error("Error message")
+
+	wait()
+
+	checkLogFile(t, hook.infoPath, "error")
+	checkLogFile(t, hook.warnPath, "error")
+	checkLogFile(t, hook.errorPath, "error")
+}
+
+func TestFsHookInterleaved(t *testing.T) {
+	logger, hook, wait, teardown := setupLogHook(t)
+	defer teardown()
+
+	logger.WithField("counter", 0).Info("message")
+	logger.WithField("counter", 1).Warn("message")
+	logger.WithField("counter", 2).Error("message")
+	logger.WithField("counter", 3).Warn("message")
+	logger.WithField("counter", 4).Info("message")
+
+	wait()
+
+	file, err := os.Open(hook.infoPath)
+	if err != nil {
+		t.Fatalf("Failed to open file: %v", err)
+	}
+
+	scanner := bufio.NewScanner(file)
+	count := 0
+	for scanner.Scan() {
+		data := make(map[string]interface{})
+		if err := json.Unmarshal([]byte(scanner.Text()), &data); err != nil {
+			t.Fatalf("Failed to parse JSON: %v", err)
+		}
+		dataCounter := int(data["counter"].(float64))
+		if count != dataCounter {
+			t.Fatalf("Counter: want %d got %d", count, dataCounter)
+		}
+		count++
+	}
+
+	if count != 5 {
+		t.Fatalf("Lines: want 5 got %d", count)
+	}
+}
+
+func TestFSHookMultiple(t *testing.T) {
+	logger, hook, wait, teardown := setupLogHook(t)
+	defer teardown()
+
+	for i := 0; i < 100; i++ {
+		logger.WithField("counter", i).Info("message")
+	}
+
+	wait()
+
+	file, err := os.Open(hook.infoPath)
+	if err != nil {
+		t.Fatalf("Failed to open file: %v", err)
+	}
+
+	scanner := bufio.NewScanner(file)
+	count := 0
+	for scanner.Scan() {
+		data := make(map[string]interface{})
+		if err := json.Unmarshal([]byte(scanner.Text()), &data); err != nil {
+			t.Fatalf("Failed to parse JSON: %v", err)
+		}
+		dataCounter := int(data["counter"].(float64))
+		if count != dataCounter {
+			t.Fatalf("Counter: want %d got %d", count, dataCounter)
+		}
+		count++
+	}
+
+	if count != 100 {
+		t.Fatalf("Lines: want 100 got %d", count)
+	}
+}
+
+func TestFSHookConcurrent(t *testing.T) {
+	logger, hook, wait, teardown := setupLogHook(t)
+	defer teardown()
+
+	var wg sync.WaitGroup
+
+	for i := 0; i < 100; i++ {
+		wg.Add(1)
+
+		go func(counter int) {
+			defer wg.Done()
+			logger.WithField("counter", counter).Info("message")
+		}(i)
+	}
+
+	wg.Wait()
+	wait()
+
+	file, err := os.Open(hook.infoPath)
+	if err != nil {
+		t.Fatalf("Failed to open file: %v", err)
+	}
+
+	scanner := bufio.NewScanner(file)
+	count := 0
+	for scanner.Scan() {
+		data := make(map[string]interface{})
+		if err := json.Unmarshal([]byte(scanner.Text()), &data); err != nil {
+			t.Fatalf("Failed to parse JSON: %v", err)
+		}
+		count++
+	}
+
+	if count != 100 {
+		t.Fatalf("Lines: want 100 got %d", count)
+	}
+}
+
+func TestDailySchedule(t *testing.T) {
+	loc, err := time.LoadLocation("UTC")
+	if err != nil {
+		t.Fatalf("Failed to load location UTC: %s", err)
+	}
+
+	logger, hook, wait, teardown := setupLogHook(t)
+	defer teardown()
+	hook.scheduler = &DailyRotationSchedule{}
+
+	// Time ticks from 23:50 to 00:10 in 1 minute increments. Log each tick as 'counter'.
+	minutesGoneBy := 0
+	currentTime = func() time.Time {
+		minutesGoneBy += 1
+		return time.Date(2016, 10, 26, 23, 50+minutesGoneBy, 00, 0, loc)
+	}
+	for i := 0; i < 20; i++ {
+		t := time.Date(2016, 10, 26, 23, 50+i, 00, 0, loc)
+		logger.WithField("counter", i).Info("BASE " + t.Format(time.ANSIC))
+	}
+
+	wait()
+
+	// info.log.2016-10-26 should have 0 -> 9
+	checkFileHasSequentialCounts(t, hook.infoPath+".2016-10-26", 0, 9)
+
+	// info.log should have 10 -> 19 inclusive
+	checkFileHasSequentialCounts(t, hook.infoPath, 10, 19)
+}
+
+func TestDailyScheduleMultipleRotations(t *testing.T) {
+	loc, err := time.LoadLocation("UTC")
+	if err != nil {
+		t.Fatalf("Failed to load location UTC: %s", err)
+	}
+
+	logger, hook, wait, teardown := setupLogHook(t)
+	defer teardown()
+	hook.scheduler = &DailyRotationSchedule{}
+
+	// Time ticks every 12 hours from 13:37 -> 01:37 -> 13:37 -> ...
+	hoursGoneBy := 0
+	currentTime = func() time.Time {
+		hoursGoneBy += 12
+		// Start from 10/29 01:37
+		return time.Date(2016, 10, 28, 13+hoursGoneBy, 37, 00, 0, loc)
+	}
+	// log 2 lines per file, to 4 files (so 8 log lines)
+	for i := 0; i < 8; i++ {
+		ts := time.Date(2016, 10, 28, 13+((i+1)*12), 37, 00, 0, loc)
+		logger.WithField("counter", i).Infof("The time is now %s", ts)
+	}
+
+	wait()
+
+	// info.log.2016-10-29 should have 0-1
+	checkFileHasSequentialCounts(t, hook.infoPath+".2016-10-29", 0, 1)
+
+	// info.log.2016-10-30 should have 2-3
+	checkFileHasSequentialCounts(t, hook.infoPath+".2016-10-30", 2, 3)
+
+	// info.log.2016-10-31 should have 4-5
+	checkFileHasSequentialCounts(t, hook.infoPath+".2016-10-31", 4, 5)
+
+	// info.log should have 6-7 (current day is 11/01)
+	checkFileHasSequentialCounts(t, hook.infoPath, 6, 7)
+}
+
+// checkFileHasSequentialCounts based on a JSON "counter" key being a monotonically
+// incrementing integer. from and to are both inclusive.
+func checkFileHasSequentialCounts(t *testing.T, filepath string, from, to int) {
+	t.Logf("checkFileHasSequentialCounts(%s,%d,%d)", filepath, from, to)
+
+	file, err := os.Open(filepath)
+	if err != nil {
+		t.Fatalf("Failed to open file: %v", err)
+		return
+	}
+
+	defer file.Close()
+	scanner := bufio.NewScanner(file)
+	count := from
+	for scanner.Scan() {
+		data := make(map[string]interface{})
+		if err := json.Unmarshal([]byte(scanner.Text()), &data); err != nil {
+			t.Fatalf("%s : Failed to parse JSON: %v", file.Name(), err)
+		}
+		dataCounter := int(data["counter"].(float64))
+		t.Logf("%s want %d got %d", file.Name(), count, dataCounter)
+		if count != dataCounter {
+			t.Fatalf("%s : Counter: want %d got %d", file.Name(), count, dataCounter)
+		}
+
+		count++
+	}
+	count-- // never hit the next value
+
+	if count != to {
+		t.Fatalf("%s EOF: Want count %d got %d", file.Name(), to, count)
+	}
+}
+
+func setupLogHook(t *testing.T) (logger *log.Logger, hook *fsHook, wait func(), teardown func()) {
+	dir, err := ioutil.TempDir("", "TestFSHook")
+	if err != nil {
+		t.Fatalf("Failed to make temporary directory: %v", err)
+	}
+
+	infoPath := filepath.Join(dir, "info.log")
+	warnPath := filepath.Join(dir, "warn.log")
+	errorPath := filepath.Join(dir, "error.log")
+
+	hook = NewFSHook(infoPath, warnPath, errorPath, nil, nil).(*fsHook)
+
+	logger = log.New()
+	logger.Hooks.Add(hook)
+
+	wait = func() {
+		for atomic.LoadInt32(&hook.queueSize) != 0 {
+			runtime.Gosched()
+		}
+	}
+
+	teardown = func() {
+		os.RemoveAll(dir)
+	}
+
+	return
+}
+
+func checkLogFile(t *testing.T, path, expectedLevel string) {
+	contents, err := ioutil.ReadFile(path)
+	if err != nil {
+		t.Fatalf("Failed to read file: %v", err)
+	}
+
+	data := make(map[string]interface{})
+	if err := json.Unmarshal(contents, &data); err != nil {
+		t.Fatalf("Failed to parse JSON: %v", err)
+	}
+
+	if data["level"] != expectedLevel {
+		t.Fatalf("level: want %q got %q", expectedLevel, data["level"])
+	}
+
+	if data[fieldName] != fieldValue {
+		t.Fatalf("%s: want %q got %q", fieldName, fieldValue, data[fieldName])
+	}
+}