// handleFetchData handles a request for the current nodes meta data
func (r *rpc) handleFetchData(req *internal.FetchDataRequest) (*internal.FetchDataResponse, error) {
var (
b []byte
data *Data
err error
)
for {
data = r.store.cachedData()
if data.Index != req.GetIndex() {
b, err = data.MarshalBinary()
if err != nil {
return nil, err
}
break
}
if !req.GetBlocking() {
break
}
if err := r.store.WaitForDataChanged(); err != nil {
return nil, err
}
}
return &internal.FetchDataResponse{
Header: &internal.ResponseHeader{
OK: proto.Bool(true),
},
Index: proto.Uint64(data.Index),
Term: proto.Uint64(data.Term),
Data: b}, nil
}
// handleJoinRequest handles a request to join the cluster
func (r *rpc) handleJoinRequest(req *internal.JoinRequest) (*internal.JoinResponse, error) {
r.traceCluster("join request from: %v", *req.Addr)
node, err := func() (*NodeInfo, error) {
// attempt to create the node
node, err := r.store.CreateNode(*req.Addr)
// if it exists, return the existing node
if err == ErrNodeExists {
return r.store.NodeByHost(*req.Addr)
} else if err != nil {
return nil, fmt.Errorf("create node: %v", err)
}
// FIXME: jwilder: adding raft nodes is tricky since going
// from 1 node (leader) to two kills the cluster because
// quorum is lost after adding the second node. For now,
// can only add non-raft enabled nodes
// If we have less than 3 nodes, add them as raft peers
// if len(r.store.Peers()) < MaxRaftNodes {
// if err = r.store.AddPeer(*req.Addr); err != nil {
// return node, fmt.Errorf("add peer: %v", err)
// }
// }
return node, err
}()
nodeID := uint64(0)
if node != nil {
nodeID = node.ID
}
if err != nil {
return nil, err
}
return &internal.JoinResponse{
Header: &internal.ResponseHeader{
OK: proto.Bool(true),
},
//EnableRaft: proto.Bool(contains(r.store.Peers(), *req.Addr)),
EnableRaft: proto.Bool(false),
RaftNodes: r.store.Peers(),
NodeID: proto.Uint64(nodeID),
}, err
}
func newTestMessage() *pb.MyMessage {
msg := &pb.MyMessage{
Count: proto.Int32(42),
Name: proto.String("Dave"),
Quote: proto.String(`"I didn't want to go."`),
Pet: []string{"bunny", "kitty", "horsey"},
Inner: &pb.InnerMessage{
Host: proto.String("footrest.syd"),
Port: proto.Int32(7001),
Connected: proto.Bool(true),
},
Others: []*pb.OtherMessage{
{
Key: proto.Int64(0xdeadbeef),
Value: []byte{1, 65, 7, 12},
},
{
Weight: proto.Float32(6.022),
Inner: &pb.InnerMessage{
Host: proto.String("lesha.mtv"),
Port: proto.Int32(8002),
},
},
},
Bikeshed: pb.MyMessage_BLUE.Enum(),
Somegroup: &pb.MyMessage_SomeGroup{
GroupField: proto.Int32(8),
},
// One normally wouldn't do this.
// This is an undeclared tag 13, as a varint (wire type 0) with value 4.
XXX_unrecognized: []byte{13<<3 | 0, 4},
}
ext := &pb.Ext{
Data: proto.String("Big gobs for big rats"),
}
if err := proto.SetExtension(msg, pb.E_Ext_More, ext); err != nil {
panic(err)
}
greetings := []string{"adg", "easy", "cow"}
if err := proto.SetExtension(msg, pb.E_Greeting, greetings); err != nil {
panic(err)
}
// Add an unknown extension. We marshal a pb.Ext, and fake the ID.
b, err := proto.Marshal(&pb.Ext{Data: proto.String("3G skiing")})
if err != nil {
panic(err)
}
b = append(proto.EncodeVarint(201<<3|proto.WireBytes), b...)
proto.SetRawExtension(msg, 201, b)
// Extensions can be plain fields, too, so let's test that.
b = append(proto.EncodeVarint(202<<3|proto.WireVarint), 19)
proto.SetRawExtension(msg, 202, b)
return msg
}
func (r *rpc) sendError(conn net.Conn, msg string) {
r.traceCluster(msg)
resp := &internal.ErrorResponse{
Header: &internal.ResponseHeader{
OK: proto.Bool(false),
Error: proto.String(msg),
},
}
r.sendResponse(conn, internal.RPCType_Error, resp)
}
// marshal serializes to a protobuf representation.
func (ui UserInfo) marshal() *internal.UserInfo {
pb := &internal.UserInfo{
Name: proto.String(ui.Name),
Hash: proto.String(ui.Hash),
Admin: proto.Bool(ui.Admin),
}
for database, privilege := range ui.Privileges {
pb.Privileges = append(pb.Privileges, &internal.UserPrivilege{
Database: proto.String(database),
Privilege: proto.Int32(int32(privilege)),
})
}
return pb
}
// fetchMetaData returns the latest copy of the meta store data from the current
// leader.
func (r *rpc) fetchMetaData(blocking bool) (*Data, error) {
assert(r.store != nil, "store is nil")
// Retrieve the current known leader.
leader := r.store.Leader()
if leader == "" {
return nil, errors.New("no leader")
}
var index, term uint64
data := r.store.cachedData()
if data != nil {
index = data.Index
term = data.Index
}
resp, err := r.call(leader, &internal.FetchDataRequest{
Index: proto.Uint64(index),
Term: proto.Uint64(term),
Blocking: proto.Bool(blocking),
})
if err != nil {
return nil, err
}
switch t := resp.(type) {
case *internal.FetchDataResponse:
// If data is nil, then the term and index we sent matches the leader
if t.GetData() == nil {
return nil, nil
}
ms := &Data{}
if err := ms.UnmarshalBinary(t.GetData()); err != nil {
return nil, fmt.Errorf("rpc unmarshal metadata: %v", err)
}
return ms, nil
case *internal.ErrorResponse:
return nil, fmt.Errorf("rpc failed: %s", t.GetHeader().GetError())
default:
return nil, fmt.Errorf("rpc failed: unknown response type: %v", t.String())
}
}
import (
"testing"
"github.com/nathanielc/morgoth/Godeps/_workspace/src/github.com/gogo/protobuf/proto"
pb "github.com/nathanielc/morgoth/Godeps/_workspace/src/github.com/gogo/protobuf/proto/testdata"
)
var cloneTestMessage = &pb.MyMessage{
Count: proto.Int32(42),
Name: proto.String("Dave"),
Pet: []string{"bunny", "kitty", "horsey"},
Inner: &pb.InnerMessage{
Host: proto.String("niles"),
Port: proto.Int32(9099),
Connected: proto.Bool(true),
},
Others: []*pb.OtherMessage{
{
Value: []byte("some bytes"),
},
},
Somegroup: &pb.MyMessage_SomeGroup{
GroupField: proto.Int32(6),
},
RepBytes: [][]byte{[]byte("sham"), []byte("wow")},
}
func init() {
ext := &pb.Ext{
Data: proto.String("extension"),
// handleRPCConn reads a command from the connection and executes it.
func (r *rpc) handleRPCConn(conn net.Conn) {
defer conn.Close()
// RPC connections should execute on the leader. If we are not the leader,
// proxy the connection to the leader so that clients an connect to any node
// in the cluster.
r.traceCluster("rpc connection from: %v", conn.RemoteAddr())
if !r.store.IsLeader() {
r.proxyLeader(conn.(*net.TCPConn))
return
}
// Read and execute request.
typ, resp, err := func() (internal.RPCType, proto.Message, error) {
// Read request size.
var sz uint64
if err := binary.Read(conn, binary.BigEndian, &sz); err != nil {
return internal.RPCType_Error, nil, fmt.Errorf("read size: %s", err)
}
if sz == 0 {
return 0, nil, fmt.Errorf("invalid message size: %d", sz)
}
if sz >= MaxMessageSize {
return 0, nil, fmt.Errorf("max message size of %d exceeded: %d", MaxMessageSize, sz)
}
// Read request.
buf := make([]byte, sz)
if _, err := io.ReadFull(conn, buf); err != nil {
return internal.RPCType_Error, nil, fmt.Errorf("read request: %s", err)
}
// Determine the RPC type
rpcType := internal.RPCType(btou64(buf[0:8]))
buf = buf[8:]
r.traceCluster("recv %v request on: %v", rpcType, conn.RemoteAddr())
switch rpcType {
case internal.RPCType_FetchData:
var req internal.FetchDataRequest
if err := proto.Unmarshal(buf, &req); err != nil {
return internal.RPCType_Error, nil, fmt.Errorf("fetch request unmarshal: %v", err)
}
resp, err := r.handleFetchData(&req)
return rpcType, resp, err
case internal.RPCType_Join:
var req internal.JoinRequest
if err := proto.Unmarshal(buf, &req); err != nil {
return internal.RPCType_Error, nil, fmt.Errorf("join request unmarshal: %v", err)
}
resp, err := r.handleJoinRequest(&req)
return rpcType, resp, err
default:
return internal.RPCType_Error, nil, fmt.Errorf("unknown rpc type:%v", rpcType)
}
}()
// Handle unexpected RPC errors
if err != nil {
resp = &internal.ErrorResponse{
Header: &internal.ResponseHeader{
OK: proto.Bool(false),
},
}
typ = internal.RPCType_Error
}
// Set the status header and error message
if reply, ok := resp.(Reply); ok {
reply.GetHeader().OK = proto.Bool(err == nil)
if err != nil {
reply.GetHeader().Error = proto.String(err.Error())
}
}
r.sendResponse(conn, typ, resp)
}
