zrepl/cmd/replication.go
Christian Schwarz 8cca0a8547 Initial working version
Summary:
* Logging is still bad
* test output in a lot of placed
* FIXMEs every where

Test Plan: None, just review

Differential Revision: https://phabricator.cschwarz.com/D2
2018-06-24 10:44:00 +02:00

402 lines
10 KiB
Go

package cmd
import (
"fmt"
"github.com/zrepl/zrepl/cmd/replication"
"github.com/problame/go-streamrpc"
"github.com/zrepl/zrepl/zfs"
"io"
"github.com/pkg/errors"
"github.com/golang/protobuf/proto"
"bytes"
"os"
)
type InitialReplPolicy string
const (
InitialReplPolicyMostRecent InitialReplPolicy = "most_recent"
InitialReplPolicyAll InitialReplPolicy = "all"
)
const DEFAULT_INITIAL_REPL_POLICY = InitialReplPolicyMostRecent
// SenderEndpoint implements replication.ReplicationEndpoint for a sending side
type SenderEndpoint struct {
FSFilter zfs.DatasetFilter
FilesystemVersionFilter zfs.FilesystemVersionFilter
}
func NewSenderEndpoint(fsf zfs.DatasetFilter, fsvf zfs.FilesystemVersionFilter) *SenderEndpoint {
return &SenderEndpoint{fsf, fsvf}
}
func (p *SenderEndpoint) ListFilesystems() ([]*replication.Filesystem, error) {
fss, err := zfs.ZFSListMapping(p.FSFilter)
if err != nil {
return nil, err
}
rfss := make([]*replication.Filesystem, len(fss))
for i := range fss {
rfss[i] = &replication.Filesystem{
Path: fss[i].ToString(),
// FIXME: not supporting ResumeToken yet
}
}
return rfss, nil
}
func (p *SenderEndpoint) ListFilesystemVersions(fs string) ([]*replication.FilesystemVersion, error) {
dp, err := zfs.NewDatasetPath(fs)
if err != nil {
return nil, err
}
pass, err := p.FSFilter.Filter(dp)
if err != nil {
return nil, err
}
if !pass {
return nil, replication.NewFilteredError(fs)
}
fsvs, err := zfs.ZFSListFilesystemVersions(dp, p.FilesystemVersionFilter)
if err != nil {
return nil, err
}
rfsvs := make([]*replication.FilesystemVersion, len(fsvs))
for i := range fsvs {
rfsvs[i] = replication.FilesystemVersionFromZFS(fsvs[i])
}
return rfsvs, nil
}
func (p *SenderEndpoint) Send(r *replication.SendReq) (*replication.SendRes, io.Reader, error) {
os.Stderr.WriteString("sending " + r.String() + "\n")
dp, err := zfs.NewDatasetPath(r.Filesystem)
if err != nil {
return nil, nil, err
}
pass, err := p.FSFilter.Filter(dp)
if err != nil {
return nil, nil, err
}
if !pass {
return nil, nil, replication.NewFilteredError(r.Filesystem)
}
stream, err := zfs.ZFSSend(r.Filesystem, r.From, r.To)
if err != nil {
return nil, nil, err
}
return &replication.SendRes{}, stream, nil
}
func (p *SenderEndpoint) Receive(r *replication.ReceiveReq, sendStream io.Reader) (error) {
return fmt.Errorf("sender endpoint does not receive")
}
// ReceiverEndpoint implements replication.ReplicationEndpoint for a receiving side
type ReceiverEndpoint struct {
fsmapInv *DatasetMapFilter
fsmap *DatasetMapFilter
fsvf zfs.FilesystemVersionFilter
}
func NewReceiverEndpoint(fsmap *DatasetMapFilter, fsvf zfs.FilesystemVersionFilter) (*ReceiverEndpoint, error) {
fsmapInv, err := fsmap.Invert()
if err != nil {
return nil, err
}
return &ReceiverEndpoint{fsmapInv, fsmap, fsvf}, nil
}
func (e *ReceiverEndpoint) ListFilesystems() ([]*replication.Filesystem, error) {
filtered, err := zfs.ZFSListMapping(e.fsmapInv.AsFilter())
if err != nil {
return nil, errors.Wrap(err, "error checking client permission")
}
fss := make([]*replication.Filesystem, len(filtered))
for i, a := range filtered {
mapped, err := e.fsmapInv.Map(a)
if err != nil {
return nil, err
}
fss[i] = &replication.Filesystem{Path: mapped.ToString()}
}
return fss, nil
}
func (e *ReceiverEndpoint) ListFilesystemVersions(fs string) ([]*replication.FilesystemVersion, error) {
p, err := zfs.NewDatasetPath(fs)
if err != nil {
return nil, err
}
lp, err := e.fsmap.Map(p)
if err != nil {
return nil, err
}
if lp == nil {
return nil, errors.New("access to filesystem denied")
}
fsvs, err := zfs.ZFSListFilesystemVersions(lp, e.fsvf)
if err != nil {
return nil, err
}
rfsvs := make([]*replication.FilesystemVersion, len(fsvs))
for i := range fsvs {
rfsvs[i] = replication.FilesystemVersionFromZFS(fsvs[i])
}
return rfsvs, nil
}
func (e *ReceiverEndpoint) Send(req *replication.SendReq) (*replication.SendRes, io.Reader, error) {
return nil, nil, errors.New("receiver endpoint does not send")
}
func (e *ReceiverEndpoint) Receive(req *replication.ReceiveReq, sendStream io.Reader) error {
p, err := zfs.NewDatasetPath(req.Filesystem)
if err != nil {
return err
}
lp, err := e.fsmap.Map(p)
if err != nil {
return err
}
if lp == nil {
return errors.New("receive to filesystem denied")
}
// create placeholder parent filesystems as appropriate
var visitErr error
f := zfs.NewDatasetPathForest()
f.Add(lp)
f.WalkTopDown(func(v zfs.DatasetPathVisit) (visitChildTree bool) {
if v.Path.Equal(lp) {
return false
}
_, err := zfs.ZFSGet(v.Path, []string{zfs.ZREPL_PLACEHOLDER_PROPERTY_NAME})
if err != nil {
os.Stderr.WriteString("error zfsget " + err.Error() + "\n")
// interpret this as an early exit of the zfs binary due to the fs not existing
if err := zfs.ZFSCreatePlaceholderFilesystem(v.Path); err != nil {
os.Stderr.WriteString("error creating placeholder " + v.Path.ToString() + "\n")
visitErr = err
return false
}
}
os.Stderr.WriteString(v.Path.ToString() + " exists\n")
return true // leave this fs as is
})
if visitErr != nil {
return visitErr
}
needForceRecv := false
props, err := zfs.ZFSGet(lp, []string{zfs.ZREPL_PLACEHOLDER_PROPERTY_NAME})
if err == nil {
if isPlaceholder, _ := zfs.IsPlaceholder(lp, props.Get(zfs.ZREPL_PLACEHOLDER_PROPERTY_NAME)); isPlaceholder {
needForceRecv = true
}
}
args := make([]string, 0, 1)
if needForceRecv {
args = append(args, "-F")
}
os.Stderr.WriteString("receiving...\n")
if err := zfs.ZFSRecv(lp.ToString(), sendStream, args...); err != nil {
// FIXME sendStream is on the wire and contains data, if we don't consume it, wire must be closed
return err
}
return nil
}
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
// RPC STUBS
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
const (
RPCListFilesystems = "ListFilesystems"
RPCListFilesystemVersions = "ListFilesystemVersions"
RPCReceive = "Receive"
RPCSend = "Send"
)
type RemoteEndpoint struct {
*streamrpc.Client
}
func (s RemoteEndpoint) ListFilesystems() ([]*replication.Filesystem, error) {
req := replication.ListFilesystemReq{}
b, err := proto.Marshal(&req)
if err != nil {
return nil, err
}
rb, rs, err := s.RequestReply(RPCListFilesystems, bytes.NewBuffer(b), nil)
if err != nil {
return nil, err
}
if rs != nil {
os.Stderr.WriteString(fmt.Sprintf("%#v\n", rs))
s.Close() // FIXME
return nil, errors.New("response contains unexpected stream")
}
var res replication.ListFilesystemRes
if err := proto.Unmarshal(rb.Bytes(), &res); err != nil {
return nil, err
}
return res.Filesystems, nil
}
func (s RemoteEndpoint) ListFilesystemVersions(fs string) ([]*replication.FilesystemVersion, error) {
req := replication.ListFilesystemVersionsReq{
Filesystem: fs,
}
b, err := proto.Marshal(&req)
if err != nil {
return nil, err
}
rb, rs, err := s.RequestReply(RPCListFilesystemVersions, bytes.NewBuffer(b), nil)
if err != nil {
return nil, err
}
if rs != nil {
s.Close() // FIXME
return nil, errors.New("response contains unexpected stream")
}
var res replication.ListFilesystemVersionsRes
if err := proto.Unmarshal(rb.Bytes(), &res); err != nil {
return nil, err
}
return res.Versions, nil
}
func (s RemoteEndpoint) Send(r *replication.SendReq) (*replication.SendRes, io.Reader, error) {
b, err := proto.Marshal(r)
if err != nil {
return nil, nil, err
}
rb, rs, err := s.RequestReply(RPCSend, bytes.NewBuffer(b), nil)
if err != nil {
return nil, nil, err
}
if rs == nil {
return nil, nil, errors.New("response does not contain a stream")
}
var res replication.SendRes
if err := proto.Unmarshal(rb.Bytes(), &res); err != nil {
s.Close() // FIXME
return nil, nil, err
}
// FIXME make sure the consumer will read the reader until the end...
return &res, rs, nil
}
func (s RemoteEndpoint) Receive(r *replication.ReceiveReq, sendStream io.Reader) (error) {
b, err := proto.Marshal(r)
if err != nil {
return err
}
rb, rs, err := s.RequestReply(RPCReceive, bytes.NewBuffer(b), sendStream)
if err != nil {
s.Close() // FIXME
return err
}
if rs != nil {
return errors.New("response contains unexpected stream")
}
var res replication.ReceiveRes
if err := proto.Unmarshal(rb.Bytes(), &res); err != nil {
return err
}
return nil
}
type HandlerAdaptor struct {
ep replication.ReplicationEndpoint
}
func (a *HandlerAdaptor) Handle(endpoint string, reqStructured *bytes.Buffer, reqStream io.Reader) (resStructured *bytes.Buffer, resStream io.Reader, err error) {
switch endpoint {
case RPCListFilesystems:
var req replication.ListFilesystemReq
if err := proto.Unmarshal(reqStructured.Bytes(), &req); err != nil {
return nil, nil, err
}
fsses, err := a.ep.ListFilesystems()
if err != nil {
return nil, nil, err
}
res := &replication.ListFilesystemRes{
Filesystems: fsses,
}
b, err := proto.Marshal(res)
if err != nil {
return nil, nil, err
}
return bytes.NewBuffer(b), nil, nil
case RPCListFilesystemVersions:
var req replication.ListFilesystemVersionsReq
if err := proto.Unmarshal(reqStructured.Bytes(), &req); err != nil {
return nil, nil, err
}
fsvs, err := a.ep.ListFilesystemVersions(req.Filesystem)
if err != nil {
return nil, nil, err
}
res := &replication.ListFilesystemVersionsRes{
Versions: fsvs,
}
b, err := proto.Marshal(res)
if err != nil {
return nil, nil, err
}
return bytes.NewBuffer(b), nil, nil
case RPCSend:
var req replication.SendReq
if err := proto.Unmarshal(reqStructured.Bytes(), &req); err != nil {
return nil, nil, err
}
res, sendStream, err := a.ep.Send(&req)
if err != nil {
return nil, nil, err
}
b, err := proto.Marshal(res)
if err != nil {
return nil, nil, err
}
return bytes.NewBuffer(b), sendStream, err
case RPCReceive:
var req replication.ReceiveReq
if err := proto.Unmarshal(reqStructured.Bytes(), &req); err != nil {
return nil, nil, err
}
err := a.ep.Receive(&req, reqStream)
if err != nil {
return nil, nil, err
}
b, err := proto.Marshal(&replication.ReceiveRes{})
if err != nil {
return nil, nil, err
}
return bytes.NewBuffer(b), nil, err
default:
return nil, nil, errors.New("no handler for given endpoint")
}
}