endpoint: refactor, fix stale holds on initial replication, holds release subcmds
- endpoint abstractions now share an interface `Abstraction`
- pkg endpoint now has a query facitilty (`ListAbstractions`) which is
used to find on-disk
- step holds and bookmarks
- replication cursors (v1, v2)
- last-received-holds
- the `zrepl holds list` command consumes endpoint.ListAbstractions
- the new `zrepl holds release-{all,stale}` commands can be used
to remove abstractions of package endpoint
Co-authored-by: InsanePrawn <insane.prawny@gmail.com>
supersedes #282
fixes #280
fixes #278
This commit is contained in:
Christian Schwarz
+3
-178
@@ -7,8 +7,6 @@ import (
|
||||
"fmt"
|
||||
"os"
|
||||
"os/exec"
|
||||
"sort"
|
||||
"strconv"
|
||||
"strings"
|
||||
"syscall"
|
||||
|
||||
@@ -36,12 +34,9 @@ func ValidHoldTag(tag string) error {
|
||||
}
|
||||
|
||||
// Idemptotent: does not return an error if the tag already exists
|
||||
func ZFSHold(ctx context.Context, fs string, v ZFSSendArgVersion, tag string) error {
|
||||
if err := v.ValidateInMemory(fs); err != nil {
|
||||
return errors.Wrap(err, "invalid version")
|
||||
}
|
||||
func ZFSHold(ctx context.Context, fs string, v FilesystemVersion, tag string) error {
|
||||
if !v.IsSnapshot() {
|
||||
return errors.Errorf("can only hold snapshots, got %s", v.RelName)
|
||||
return errors.Errorf("can only hold snapshots, got %s", v.RelName())
|
||||
}
|
||||
|
||||
if err := validateNotEmpty("tag", tag); err != nil {
|
||||
@@ -131,177 +126,7 @@ func ZFSRelease(ctx context.Context, tag string, snaps ...string) error {
|
||||
debug("zfs release: no such tag lines=%v otherLines=%v", noSuchTagLines, otherLines)
|
||||
}
|
||||
if len(otherLines) > 0 {
|
||||
return fmt.Errorf("unknown zfs error while releasing hold with tag %q: unidentified stderr lines\n%s", tag, strings.Join(otherLines, "\n"))
|
||||
return fmt.Errorf("unknown zfs error while releasing hold with tag %q:\n%s", tag, strings.Join(otherLines, "\n"))
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Idempotent: if the hold doesn't exist, this is not an error
|
||||
func ZFSReleaseAllOlderAndIncludingGUID(ctx context.Context, fs string, snapOrBookmarkGuid uint64, tag string) error {
|
||||
return doZFSReleaseAllOlderAndIncOrExcludingGUID(ctx, fs, snapOrBookmarkGuid, tag, true)
|
||||
}
|
||||
|
||||
// Idempotent: if the hold doesn't exist, this is not an error
|
||||
func ZFSReleaseAllOlderThanGUID(ctx context.Context, fs string, snapOrBookmarkGuid uint64, tag string) error {
|
||||
return doZFSReleaseAllOlderAndIncOrExcludingGUID(ctx, fs, snapOrBookmarkGuid, tag, false)
|
||||
}
|
||||
|
||||
type zfsReleaseAllOlderAndIncOrExcludingGUIDZFSListLine struct {
|
||||
entityType EntityType
|
||||
name string
|
||||
createtxg uint64
|
||||
guid uint64
|
||||
userrefs uint64 // always 0 for bookmarks
|
||||
}
|
||||
|
||||
func doZFSReleaseAllOlderAndIncOrExcludingGUID(ctx context.Context, fs string, snapOrBookmarkGuid uint64, tag string, includeGuid bool) error {
|
||||
// TODO channel program support still unreleased but
|
||||
// might be a huge performance improvement
|
||||
// https://github.com/zfsonlinux/zfs/pull/7902/files
|
||||
|
||||
if err := validateZFSFilesystem(fs); err != nil {
|
||||
return errors.Wrap(err, "`fs` is not a valid filesystem path")
|
||||
}
|
||||
if tag == "" {
|
||||
return fmt.Errorf("`tag` must not be empty`")
|
||||
}
|
||||
|
||||
output, err := exec.CommandContext(ctx,
|
||||
"zfs", "list", "-o", "type,name,createtxg,guid,userrefs",
|
||||
"-H", "-t", "snapshot,bookmark", "-r", "-d", "1", fs).CombinedOutput()
|
||||
if err != nil {
|
||||
return &ZFSError{output, errors.Wrap(err, "cannot list snapshots and their userrefs")}
|
||||
}
|
||||
|
||||
lines, err := doZFSReleaseAllOlderAndIncOrExcludingGUIDParseListOutput(output)
|
||||
if err != nil {
|
||||
return errors.Wrap(err, "unexpected ZFS output")
|
||||
}
|
||||
|
||||
releaseSnaps, err := doZFSReleaseAllOlderAndIncOrExcludingGUIDFindSnapshots(snapOrBookmarkGuid, includeGuid, lines)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
if len(releaseSnaps) == 0 {
|
||||
return nil
|
||||
}
|
||||
return ZFSRelease(ctx, tag, releaseSnaps...)
|
||||
}
|
||||
|
||||
func doZFSReleaseAllOlderAndIncOrExcludingGUIDParseListOutput(output []byte) ([]zfsReleaseAllOlderAndIncOrExcludingGUIDZFSListLine, error) {
|
||||
|
||||
scan := bufio.NewScanner(bytes.NewReader(output))
|
||||
|
||||
var lines []zfsReleaseAllOlderAndIncOrExcludingGUIDZFSListLine
|
||||
|
||||
for scan.Scan() {
|
||||
const numCols = 5
|
||||
comps := strings.SplitN(scan.Text(), "\t", numCols)
|
||||
if len(comps) != numCols {
|
||||
return nil, fmt.Errorf("not %d columns\n%s", numCols, output)
|
||||
}
|
||||
dstype := comps[0]
|
||||
name := comps[1]
|
||||
|
||||
var entityType EntityType
|
||||
switch dstype {
|
||||
case "snapshot":
|
||||
entityType = EntityTypeSnapshot
|
||||
case "bookmark":
|
||||
entityType = EntityTypeBookmark
|
||||
default:
|
||||
return nil, fmt.Errorf("column 0 is %q, expecting \"snapshot\" or \"bookmark\"", dstype)
|
||||
}
|
||||
|
||||
createtxg, err := strconv.ParseUint(comps[2], 10, 64)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("cannot parse createtxg %q: %s\n%s", comps[2], err, output)
|
||||
}
|
||||
|
||||
guid, err := strconv.ParseUint(comps[3], 10, 64)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("cannot parse guid %q: %s\n%s", comps[3], err, output)
|
||||
}
|
||||
|
||||
var userrefs uint64
|
||||
switch entityType {
|
||||
case EntityTypeBookmark:
|
||||
if comps[4] != "-" {
|
||||
return nil, fmt.Errorf("entity type \"bookmark\" should have userrefs=\"-\", got %q", comps[4])
|
||||
}
|
||||
userrefs = 0
|
||||
case EntityTypeSnapshot:
|
||||
userrefs, err = strconv.ParseUint(comps[4], 10, 64) // shadow
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("cannot parse userrefs %q: %s\n%s", comps[4], err, output)
|
||||
}
|
||||
default:
|
||||
panic(entityType)
|
||||
}
|
||||
|
||||
lines = append(lines, zfsReleaseAllOlderAndIncOrExcludingGUIDZFSListLine{
|
||||
entityType: entityType,
|
||||
name: name,
|
||||
createtxg: createtxg,
|
||||
guid: guid,
|
||||
userrefs: userrefs,
|
||||
})
|
||||
}
|
||||
|
||||
return lines, nil
|
||||
|
||||
}
|
||||
|
||||
func doZFSReleaseAllOlderAndIncOrExcludingGUIDFindSnapshots(snapOrBookmarkGuid uint64, includeGuid bool, lines []zfsReleaseAllOlderAndIncOrExcludingGUIDZFSListLine) (releaseSnaps []string, err error) {
|
||||
|
||||
// sort lines by createtxg,(snap < bookmark)
|
||||
// we cannot do this using zfs list -s because `type` is not a
|
||||
sort.Slice(lines, func(i, j int) (less bool) {
|
||||
if lines[i].createtxg == lines[j].createtxg {
|
||||
iET := func(t EntityType) int {
|
||||
switch t {
|
||||
case EntityTypeSnapshot:
|
||||
return 0
|
||||
case EntityTypeBookmark:
|
||||
return 1
|
||||
default:
|
||||
panic("unexpected entity type " + t.String())
|
||||
}
|
||||
}
|
||||
return iET(lines[i].entityType) < iET(lines[j].entityType)
|
||||
}
|
||||
return lines[i].createtxg < lines[j].createtxg
|
||||
})
|
||||
|
||||
// iterate over snapshots oldest to newest and collect snapshots that have holds and
|
||||
// are older than (inclusive or exclusive, depends on includeGuid) a snapshot or bookmark
|
||||
// with snapOrBookmarkGuid
|
||||
foundGuid := false
|
||||
for _, line := range lines {
|
||||
if line.guid == snapOrBookmarkGuid {
|
||||
foundGuid = true
|
||||
}
|
||||
if line.userrefs > 0 {
|
||||
if !foundGuid || (foundGuid && includeGuid) {
|
||||
// only snapshots have userrefs > 0, no need to check entityType
|
||||
releaseSnaps = append(releaseSnaps, line.name)
|
||||
}
|
||||
}
|
||||
if foundGuid {
|
||||
// The secondary key in sorting (snap < bookmark) guarantees that we
|
||||
// A) either found the snapshot with snapOrBookmarkGuid
|
||||
// B) or no snapshot with snapGuid exists, but one or more bookmarks of it exists
|
||||
// In the case of A, we already added the snapshot to releaseSnaps if includeGuid requests it,
|
||||
// and can ignore possible subsequent bookmarks of the snapshot.
|
||||
// In the case of B, there is nothing to add to releaseSnaps.
|
||||
break
|
||||
}
|
||||
}
|
||||
|
||||
if !foundGuid {
|
||||
return nil, fmt.Errorf("cannot find snapshot or bookmark with guid %v", snapOrBookmarkGuid)
|
||||
}
|
||||
|
||||
return releaseSnaps, nil
|
||||
}
|
||||
|
||||
Reference in New Issue
Block a user