Import metric store packages

internal/memorystore/archive.go

@@ -0,0 +1,190 @@
+// Copyright (C) NHR@FAU, University Erlangen-Nuremberg.
+// All rights reserved. This file is part of cc-backend.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+package memorystore
+
+import (
+	"archive/zip"
+	"bufio"
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	cclog "github.com/ClusterCockpit/cc-lib/ccLogger"
+)
+
+func Archiving(wg *sync.WaitGroup, ctx context.Context) {
+	go func() {
+		defer wg.Done()
+		d, err := time.ParseDuration(Keys.Archive.Interval)
+		if err != nil {
+			cclog.Fatalf("error parsing archive interval duration: %v\n", err)
+		}
+		if d <= 0 {
+			return
+		}
+
+		ticks := func() <-chan time.Time {
+			if d <= 0 {
+				return nil
+			}
+			return time.NewTicker(d).C
+		}()
+		for {
+			select {
+			case <-ctx.Done():
+				return
+			case <-ticks:
+				t := time.Now().Add(-d)
+				cclog.Infof("start archiving checkpoints (older than %s)...\n", t.Format(time.RFC3339))
+				n, err := ArchiveCheckpoints(Keys.Checkpoints.RootDir,
+					Keys.Archive.RootDir, t.Unix(), Keys.Archive.DeleteInstead)
+
+				if err != nil {
+					cclog.Warnf("archiving failed: %s\n", err.Error())
+				} else {
+					cclog.Infof("done: %d files zipped and moved to archive\n", n)
+				}
+			}
+		}
+	}()
+}
+
+var ErrNoNewData error = errors.New("all data already archived")
+
+// ZIP all checkpoint files older than `from` together and write them to the `archiveDir`,
+// deleting them from the `checkpointsDir`.
+func ArchiveCheckpoints(checkpointsDir, archiveDir string, from int64, deleteInstead bool) (int, error) {
+	entries1, err := os.ReadDir(checkpointsDir)
+	if err != nil {
+		return 0, err
+	}
+
+	type workItem struct {
+		cdir, adir    string
+		cluster, host string
+	}
+
+	var wg sync.WaitGroup
+	n, errs := int32(0), int32(0)
+	work := make(chan workItem, NumWorkers)
+
+	wg.Add(NumWorkers)
+	for worker := 0; worker < NumWorkers; worker++ {
+		go func() {
+			defer wg.Done()
+			for workItem := range work {
+				m, err := archiveCheckpoints(workItem.cdir, workItem.adir, from, deleteInstead)
+				if err != nil {
+					cclog.Errorf("error while archiving %s/%s: %s", workItem.cluster, workItem.host, err.Error())
+					atomic.AddInt32(&errs, 1)
+				}
+				atomic.AddInt32(&n, int32(m))
+			}
+		}()
+	}
+
+	for _, de1 := range entries1 {
+		entries2, e := os.ReadDir(filepath.Join(checkpointsDir, de1.Name()))
+		if e != nil {
+			err = e
+		}
+
+		for _, de2 := range entries2 {
+			cdir := filepath.Join(checkpointsDir, de1.Name(), de2.Name())
+			adir := filepath.Join(archiveDir, de1.Name(), de2.Name())
+			work <- workItem{
+				adir: adir, cdir: cdir,
+				cluster: de1.Name(), host: de2.Name(),
+			}
+		}
+	}
+
+	close(work)
+	wg.Wait()
+
+	if err != nil {
+		return int(n), err
+	}
+
+	if errs > 0 {
+		return int(n), fmt.Errorf("%d errors happend while archiving (%d successes)", errs, n)
+	}
+	return int(n), nil
+}
+
+// Helper function for `ArchiveCheckpoints`.
+func archiveCheckpoints(dir string, archiveDir string, from int64, deleteInstead bool) (int, error) {
+	entries, err := os.ReadDir(dir)
+	if err != nil {
+		return 0, err
+	}
+
+	extension := Keys.Checkpoints.FileFormat
+	files, err := findFiles(entries, from, extension, false)
+	if err != nil {
+		return 0, err
+	}
+
+	if deleteInstead {
+		n := 0
+		for _, checkpoint := range files {
+			filename := filepath.Join(dir, checkpoint)
+			if err = os.Remove(filename); err != nil {
+				return n, err
+			}
+			n += 1
+		}
+		return n, nil
+	}
+
+	filename := filepath.Join(archiveDir, fmt.Sprintf("%d.zip", from))
+	f, err := os.OpenFile(filename, os.O_CREATE|os.O_WRONLY, 0o644)
+	if err != nil && os.IsNotExist(err) {
+		err = os.MkdirAll(archiveDir, 0o755)
+		if err == nil {
+			f, err = os.OpenFile(filename, os.O_CREATE|os.O_WRONLY, 0o644)
+		}
+	}
+	if err != nil {
+		return 0, err
+	}
+	defer f.Close()
+	bw := bufio.NewWriter(f)
+	defer bw.Flush()
+	zw := zip.NewWriter(bw)
+	defer zw.Close()
+
+	n := 0
+	for _, checkpoint := range files {
+		filename := filepath.Join(dir, checkpoint)
+		r, err := os.Open(filename)
+		if err != nil {
+			return n, err
+		}
+		defer r.Close()
+
+		w, err := zw.Create(checkpoint)
+		if err != nil {
+			return n, err
+		}
+
+		if _, err = io.Copy(w, r); err != nil {
+			return n, err
+		}
+
+		if err = os.Remove(filename); err != nil {
+			return n, err
+		}
+		n += 1
+	}
+
+	return n, nil
+}