WIP: Switch to new config format.

Don't use jobrun for daemon, just call JobDo() once, the job must
organize stuff itself.

Sacrifice all the oneshot commands, they will be reintroduced as
client-calls to the daemon.

cmd/config_prune_grid.go

@@ -0,0 +1,203 @@
+package cmd
+
+import (
+	"github.com/mitchellh/mapstructure"
+	"fmt"
+	"time"
+	. "github.com/zrepl/zrepl/util"
+	"github.com/pkg/errors"
+	"regexp"
+	"github.com/zrepl/zrepl/zfs"
+	"sort"
+	"strconv"
+	"strings"
+)
+
+type GridPrunePolicy struct {
+	RetentionGrid *RetentionGrid
+}
+
+
+type retentionGridAdaptor struct {
+	zfs.FilesystemVersion
+}
+
+func (a retentionGridAdaptor) Date() time.Time {
+	return a.Creation
+}
+
+func (a retentionGridAdaptor) LessThan(b RetentionGridEntry) bool {
+	return a.CreateTXG < b.(retentionGridAdaptor).CreateTXG
+}
+
+func (p *GridPrunePolicy) Prune(fs zfs.DatasetPath, versions []zfs.FilesystemVersion) (keep, remove []zfs.FilesystemVersion, err error) {
+
+	// Build adaptors for retention grid
+	adaptors := make([]RetentionGridEntry, len(versions))
+	for fsv := range versions {
+		adaptors[fsv] = retentionGridAdaptor{versions[fsv]}
+	}
+
+	sort.SliceStable(adaptors, func(i, j int) bool {
+		return adaptors[i].LessThan(adaptors[j])
+	})
+	now := adaptors[len(adaptors)-1].Date()
+
+	// Evaluate retention grid
+	keepa, removea := p.RetentionGrid.FitEntries(now, adaptors)
+
+	// Revert adaptors
+	keep = make([]zfs.FilesystemVersion, len(keepa))
+	for i := range keepa {
+		keep[i] = keepa[i].(retentionGridAdaptor).FilesystemVersion
+	}
+	remove = make([]zfs.FilesystemVersion, len(removea))
+	for i := range removea {
+		remove[i] = removea[i].(retentionGridAdaptor).FilesystemVersion
+	}
+	return
+
+}
+
+func parseGridPrunePolicy(e map[string]interface{}) (p *GridPrunePolicy, err error) {
+
+	var i struct {
+		Grid           string
+	}
+
+	if err = mapstructure.Decode(e, &i); err != nil {
+		err = errors.Wrapf(err, "mapstructure error")
+		return
+	}
+
+	p = &GridPrunePolicy{}
+
+	// Parse grid policy
+	intervals, err := parseRetentionGridIntervalsString(i.Grid)
+	if err != nil {
+		err = fmt.Errorf("cannot parse retention grid: %s", err)
+		return
+	}
+	// Assert intervals are of increasing length (not necessarily required, but indicates config mistake)
+	lastDuration := time.Duration(0)
+	for i := range intervals {
+		if intervals[i].Length < lastDuration {
+			err = fmt.Errorf("retention grid interval length must be monotonically increasing:"+
+				"interval %d is shorter than %d", i+1, i)
+			return
+		} else {
+			lastDuration = intervals[i].Length
+		}
+	}
+	p.RetentionGrid = NewRetentionGrid(intervals)
+
+	return
+}
+
+
+var durationStringRegex *regexp.Regexp = regexp.MustCompile(`^\s*(\d+)\s*(s|m|h|d|w)\s*$`)
+
+func parseDuration(e string) (d time.Duration, err error) {
+	comps := durationStringRegex.FindStringSubmatch(e)
+	if len(comps) != 3 {
+		err = fmt.Errorf("does not match regex: %s %#v", e, comps)
+		return
+	}
+
+	durationFactor, err := strconv.ParseInt(comps[1], 10, 64)
+	if err != nil {
+		return
+	}
+
+	var durationUnit time.Duration
+	switch comps[2] {
+	case "s":
+		durationUnit = time.Second
+	case "m":
+		durationUnit = time.Minute
+	case "h":
+		durationUnit = time.Hour
+	case "d":
+		durationUnit = 24 * time.Hour
+	case "w":
+		durationUnit = 24 * 7 * time.Hour
+	default:
+		err = fmt.Errorf("contains unknown time unit '%s'", comps[2])
+		return
+	}
+
+	d = time.Duration(durationFactor) * durationUnit
+	return
+
+}
+
+var retentionStringIntervalRegex *regexp.Regexp = regexp.MustCompile(`^\s*(\d+)\s*x\s*([^\(]+)\s*(\((.*)\))?\s*$`)
+
+func parseRetentionGridIntervalString(e string) (intervals []RetentionInterval, err error) {
+
+	comps := retentionStringIntervalRegex.FindStringSubmatch(e)
+	if comps == nil {
+		err = fmt.Errorf("retention string does not match expected format")
+		return
+	}
+
+	times, err := strconv.Atoi(comps[1])
+	if err != nil {
+		return nil, err
+	} else if times <= 0 {
+		return nil, fmt.Errorf("contains factor <= 0")
+	}
+
+	duration, err := parseDuration(comps[2])
+	if err != nil {
+		return nil, err
+	}
+
+	keepCount := 1
+	if comps[3] != "" {
+		// Decompose key=value, comma separated
+		// For now, only keep_count is supported
+		re := regexp.MustCompile(`^\s*keep=(.+)\s*$`)
+		res := re.FindStringSubmatch(comps[4])
+		if res == nil || len(res) != 2 {
+			err = fmt.Errorf("interval parameter contains unknown parameters")
+			return
+		}
+		if res[1] == "all" {
+			keepCount = RetentionGridKeepCountAll
+		} else {
+			keepCount, err = strconv.Atoi(res[1])
+			if err != nil {
+				err = fmt.Errorf("cannot parse keep_count value")
+				return
+			}
+		}
+	}
+
+	intervals = make([]RetentionInterval, times)
+	for i := range intervals {
+		intervals[i] = RetentionInterval{
+			Length:    duration,
+			KeepCount: keepCount,
+		}
+	}
+
+	return
+
+}
+
+func parseRetentionGridIntervalsString(s string) (intervals []RetentionInterval, err error) {
+
+	ges := strings.Split(s, "|")
+	intervals = make([]RetentionInterval, 0, 7*len(ges))
+
+	for intervalIdx, e := range ges {
+		parsed, err := parseRetentionGridIntervalString(e)
+		if err != nil {
+			return nil, fmt.Errorf("cannot parse interval %d of %d: %s: %s", intervalIdx+1, len(ges), err, strings.TrimSpace(e))
+		}
+		intervals = append(intervals, parsed...)
+	}
+
+	return
+}