lotus/journal/journal.go
2020-07-06 09:43:19 -07:00

143 lines
2.5 KiB
Go

package journal
import (
"encoding/json"
"fmt"
"os"
"path/filepath"
"sync"
"time"
logging "github.com/ipfs/go-log"
"golang.org/x/xerrors"
)
func InitializeSystemJournal(dir string) error {
if err := os.MkdirAll(dir, 0755); err != nil {
return err
}
j, err := OpenFSJournal(dir)
if err != nil {
return err
}
currentJournal = j
return nil
}
func Add(sys string, val interface{}) {
currentJournal.AddEntry(sys, val)
}
var log = logging.Logger("journal")
var currentJournal Journal
type Journal interface {
AddEntry(system string, obj interface{})
Close() error
}
// fsJournal is a basic journal backed by files on a filesystem
type fsJournal struct {
fi *os.File
fSize int64
lk sync.Mutex
journalDir string
incoming chan *JournalEntry
journalSizeLimit int64
closing chan struct{}
}
func OpenFSJournal(dir string) (*fsJournal, error) {
fsj := &fsJournal{
journalDir: dir,
incoming: make(chan *JournalEntry, 32),
journalSizeLimit: 1 << 30,
closing: make(chan struct{}),
}
if err := fsj.rollJournalFile(); err != nil {
return nil, err
}
go fsj.runLoop()
return fsj, nil
}
type JournalEntry struct {
System string
Timestamp time.Time
Val interface{}
}
func (fsj *fsJournal) putEntry(je *JournalEntry) error {
b, err := json.Marshal(je)
if err != nil {
return err
}
n, err := fsj.fi.Write(append(b, '\n'))
if err != nil {
return err
}
fsj.fSize += int64(n)
if fsj.fSize >= fsj.journalSizeLimit {
fsj.rollJournalFile()
}
return nil
}
func (fsj *fsJournal) rollJournalFile() error {
if fsj.fi != nil {
fsj.fi.Close()
}
nfi, err := os.Create(filepath.Join(fsj.journalDir, fmt.Sprintf("lotus-journal-%s.ndjson", time.Now().Format(time.RFC3339))))
if err != nil {
return xerrors.Errorf("failed to open journal file: %w", err)
}
fsj.fi = nfi
fsj.fSize = 0
return nil
}
func (fsj *fsJournal) runLoop() {
for {
select {
case je := <-fsj.incoming:
if err := fsj.putEntry(je); err != nil {
log.Errorw("failed to write out journal entry", "entry", je, "err", err)
}
case <-fsj.closing:
fsj.fi.Close()
return
}
}
}
func (fsj *fsJournal) AddEntry(system string, obj interface{}) {
je := &JournalEntry{
System: system,
Timestamp: time.Now(),
Val: obj,
}
select {
case fsj.incoming <- je:
case <-fsj.closing:
log.Warnw("journal closed but tried to log event", "entry", je)
}
}
func (fsj *fsJournal) Close() error {
close(fsj.closing)
return nil
}