zrepl/rpc/structs.go
Christian Schwarz 35dcfc234e Implement push support.
Pushing is achieved by inverting the roles on the established
connection, i.e. the client tells the server what data it should pull
from the client (PullMeRequest).

Role inversion is achieved by moving the server loop to the serverLoop
function of ByteStreamRPC, which can be called from both the Listen()
function (server-side) and the PullMeRequest() client-side function.

A donwside of this PullMe approach is that the replication policies
become part of the rpc, because the puller must follow the policy.
2017-05-20 18:17:08 +02:00

113 lines
2.4 KiB
Go

package rpc
import "io"
import "github.com/zrepl/zrepl/zfs"
type RequestId [16]byte
type RequestType uint8
const (
RTProtocolVersionRequest RequestType = 0x01
RTFilesystemRequest = 0x10
RTFilesystemVersionsRequest = 0x11
RTInitialTransferRequest = 0x12
RTIncrementalTransferRequest = 0x13
RTPullMeRequest = 0x20
RTCloseRequest = 0xf0
)
type RequestHeader struct {
Type RequestType
Id [16]byte // UUID
}
type FilesystemRequest struct {
Roots []string // may be nil, indicating interest in all filesystems
}
type FilesystemVersionsRequest struct {
Filesystem zfs.DatasetPath
}
type InitialTransferRequest struct {
Filesystem zfs.DatasetPath
FilesystemVersion zfs.FilesystemVersion
}
func (r InitialTransferRequest) Respond(snapshotReader io.Reader) {
}
type IncrementalTransferRequest struct {
Filesystem zfs.DatasetPath
From zfs.FilesystemVersion
To zfs.FilesystemVersion
}
func (r IncrementalTransferRequest) Respond(snapshotReader io.Reader) {
}
type ByteStreamRPCProtocolVersionRequest struct {
ClientVersion uint8
}
const LOCAL_TRANSPORT_IDENTITY string = "local"
const DEFAULT_INITIAL_REPL_POLICY = InitialReplPolicyMostRecent
type InitialReplPolicy string
const (
InitialReplPolicyMostRecent InitialReplPolicy = "most_recent"
InitialReplPolicyAll InitialReplPolicy = "all"
)
type PullMeRequest struct {
// if true, the other fields are undefined
Finished bool
InitialReplPolicy InitialReplPolicy
}
type CloseRequest struct {
Goodbye string
}
type ErrorId uint8
const (
ENoError ErrorId = 0
EDecodeHeader = 1
EUnknownRequestType = 2
EDecodeRequestBody = 3
EProtocolVersionMismatch = 4
EHandler = 5
)
type ResponseType uint8
const (
RNONE ResponseType = 0x0
ROK = 0x1
RFilesystems = 0x10
RFilesystemDiff = 0x11
RChunkedStream = 0x20
)
type ResponseHeader struct {
RequestId RequestId
ErrorId ErrorId
Message string
ResponseType ResponseType
}
func NewByteStreamRPCProtocolVersionRequest() ByteStreamRPCProtocolVersionRequest {
return ByteStreamRPCProtocolVersionRequest{
ClientVersion: ByteStreamRPCProtocolVersion,
}
}
func newUUID() [16]byte {
return [16]byte{}
}