Merge pull request #70 from dgraph-io/protobuffers

Protobuffers

README.md

@@ -92,14 +92,14 @@ $ tar -xzvf postings.tar.gz -C $DIR
 ```
 For quick testing, you can bring up 3 different processes of DGraph. You can of course, also set this up across multiple servers.
 ```
-go build . && ./server --instanceIdx 0 --mutations $DIR/m0 --port "8080" --postings $DIR/p0 --workers ":12345,:12346,:12347" --uids $DIR/uasync.final --workerport ":12345" &
-go build . && ./server --instanceIdx 1 --mutations $DIR/m1 --port "8081" --postings $DIR/p1 --workers ":12345,:12346,:12347" --workerport ":12346" &
-go build . && ./server --instanceIdx 2 --mutations $DIR/m2 --port "8082" --postings $DIR/p2 --workers ":12345,:12346,:12347" --workerport ":12347" &
+go build . && ./server --instanceIdx 0 --mutations $DIR/m0 --port 8080 --postings $DIR/p0 --workers ":12345,:12346,:12347" --uids $DIR/uasync.final --workerport ":12345" &
+go build . && ./server --instanceIdx 1 --mutations $DIR/m1 --port 8082 --postings $DIR/p1 --workers ":12345,:12346,:12347" --workerport ":12346" &
+go build . && ./server --instanceIdx 2 --mutations $DIR/m2 --port 8084 --postings $DIR/p2 --workers ":12345,:12346,:12347" --workerport ":12347" &
 ```
 Now you can run any of the queries mentioned in [Test Queries](https://github.com/dgraph-io/dgraph/wiki/Test-Queries).
 You can hit any of the 3 processes, they'll produce the same results.
 
-`curl localhost:8081/query -XPOST -d '{}'`
+`curl localhost:8080/query -XPOST -d '{}'`
 
 ## Installation
 Best way to do this is to refer to [Dockerfile](Dockerfile), which has the most complete

client/go/main.go

+/*
+ * Copyright 2016 DGraph Labs, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package main
+
+import (
+	"flag"
+	"fmt"
+
+	"golang.org/x/net/context"
+	"google.golang.org/grpc"
+
+	"github.com/dgraph-io/dgraph/query/pb"
+	"github.com/dgraph-io/dgraph/x"
+)
+
+var glog = x.Log("client")
+var ip = flag.String("ip", "127.0.0.1:8081", "Port to communicate with server")
+var query = flag.String("query", "", "Query sent to the server")
+
+func main() {
+	flag.Parse()
+	// TODO(pawan): Pick address for server from config
+	conn, err := grpc.Dial(*ip, grpc.WithInsecure())
+	if err != nil {
+		x.Err(glog, err).Fatal("DialTCPConnection")
+	}
+	defer conn.Close()
+
+	c := pb.NewDGraphClient(conn)
+
+	r, err := c.Query(context.Background(), &pb.GraphRequest{Query: *query})
+	if err != nil {
+		x.Err(glog, err).Fatal("Error in getting response from server")
+	}
+
+	// TODO(pawan): Remove this later
+	fmt.Printf("Subgraph %+v", r)
+
+}

query/pb/graphresponse.pb.go

+// Code generated by protoc-gen-go.
+// source: graphresponse.proto
+// DO NOT EDIT!
+
+/*
+Package pb is a generated protocol buffer package.
+
+It is generated from these files:
+	graphresponse.proto
+
+It has these top-level messages:
+	UidList
+	Result
+	GraphRequest
+	GraphResponse
+*/
+package pb
+
+import proto "github.com/golang/protobuf/proto"
+import fmt "fmt"
+import math "math"
+
+import (
+	context "golang.org/x/net/context"
+	grpc "google.golang.org/grpc"
+)
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+const _ = proto.ProtoPackageIsVersion1
+
+type UidList struct {
+	Uids []uint64 `protobuf:"varint,1,rep,name=uids" json:"uids,omitempty"`
+}
+
+func (m *UidList) Reset()                    { *m = UidList{} }
+func (m *UidList) String() string            { return proto.CompactTextString(m) }
+func (*UidList) ProtoMessage()               {}
+func (*UidList) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{0} }
+
+type Result struct {
+	Values    [][]byte   `protobuf:"bytes,1,rep,name=values,proto3" json:"values,omitempty"`
+	Uidmatrix []*UidList `protobuf:"bytes,2,rep,name=uidmatrix" json:"uidmatrix,omitempty"`
+}
+
+func (m *Result) Reset()                    { *m = Result{} }
+func (m *Result) String() string            { return proto.CompactTextString(m) }
+func (*Result) ProtoMessage()               {}
+func (*Result) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{1} }
+
+func (m *Result) GetUidmatrix() []*UidList {
+	if m != nil {
+		return m.Uidmatrix
+	}
+	return nil
+}
+
+type GraphRequest struct {
+	Query string `protobuf:"bytes,1,opt,name=query" json:"query,omitempty"`
+}
+
+func (m *GraphRequest) Reset()                    { *m = GraphRequest{} }
+func (m *GraphRequest) String() string            { return proto.CompactTextString(m) }
+func (*GraphRequest) ProtoMessage()               {}
+func (*GraphRequest) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{2} }
+
+type GraphResponse struct {
+	Attribute string           `protobuf:"bytes,1,opt,name=attribute" json:"attribute,omitempty"`
+	Result    *Result          `protobuf:"bytes,2,opt,name=result" json:"result,omitempty"`
+	Children  []*GraphResponse `protobuf:"bytes,3,rep,name=children" json:"children,omitempty"`
+}
+
+func (m *GraphResponse) Reset()                    { *m = GraphResponse{} }
+func (m *GraphResponse) String() string            { return proto.CompactTextString(m) }
+func (*GraphResponse) ProtoMessage()               {}
+func (*GraphResponse) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{3} }
+
+func (m *GraphResponse) GetResult() *Result {
+	if m != nil {
+		return m.Result
+	}
+	return nil
+}
+
+func (m *GraphResponse) GetChildren() []*GraphResponse {
+	if m != nil {
+		return m.Children
+	}
+	return nil
+}
+
+func init() {
+	proto.RegisterType((*UidList)(nil), "pb.UidList")
+	proto.RegisterType((*Result)(nil), "pb.Result")
+	proto.RegisterType((*GraphRequest)(nil), "pb.GraphRequest")
+	proto.RegisterType((*GraphResponse)(nil), "pb.GraphResponse")
+}
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ context.Context
+var _ grpc.ClientConn
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the grpc package it is being compiled against.
+const _ = grpc.SupportPackageIsVersion2
+
+// Client API for DGraph service
+
+type DGraphClient interface {
+	Query(ctx context.Context, in *GraphRequest, opts ...grpc.CallOption) (*GraphResponse, error)
+}
+
+type dGraphClient struct {
+	cc *grpc.ClientConn
+}
+
+func NewDGraphClient(cc *grpc.ClientConn) DGraphClient {
+	return &dGraphClient{cc}
+}
+
+func (c *dGraphClient) Query(ctx context.Context, in *GraphRequest, opts ...grpc.CallOption) (*GraphResponse, error) {
+	out := new(GraphResponse)
+	err := grpc.Invoke(ctx, "/pb.DGraph/Query", in, out, c.cc, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
+// Server API for DGraph service
+
+type DGraphServer interface {
+	Query(context.Context, *GraphRequest) (*GraphResponse, error)
+}
+
+func RegisterDGraphServer(s *grpc.Server, srv DGraphServer) {
+	s.RegisterService(&_DGraph_serviceDesc, srv)
+}
+
+func _DGraph_Query_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
+	in := new(GraphRequest)
+	if err := dec(in); err != nil {
+		return nil, err
+	}
+	if interceptor == nil {
+		return srv.(DGraphServer).Query(ctx, in)
+	}
+	info := &grpc.UnaryServerInfo{
+		Server:     srv,
+		FullMethod: "/pb.DGraph/Query",
+	}
+	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
+		return srv.(DGraphServer).Query(ctx, req.(*GraphRequest))
+	}
+	return interceptor(ctx, in, info, handler)
+}
+
+var _DGraph_serviceDesc = grpc.ServiceDesc{
+	ServiceName: "pb.DGraph",
+	HandlerType: (*DGraphServer)(nil),
+	Methods: []grpc.MethodDesc{
+		{
+			MethodName: "Query",
+			Handler:    _DGraph_Query_Handler,
+		},
+	},
+	Streams: []grpc.StreamDesc{},
+}
+
+var fileDescriptor0 = []byte{
+	// 255 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x09, 0x6e, 0x88, 0x02, 0xff, 0x64, 0x90, 0x4f, 0x4b, 0xc4, 0x30,
+	0x10, 0xc5, 0xed, 0xfe, 0x89, 0x76, 0x76, 0x05, 0x1d, 0x45, 0x8a, 0x28, 0x48, 0xf0, 0xb0, 0x1e,
+	0xec, 0x61, 0xbd, 0xf8, 0x01, 0x04, 0x0f, 0x7a, 0x71, 0xc0, 0x0f, 0xd0, 0xda, 0xe0, 0x06, 0xea,
+	0x36, 0x26, 0xa9, 0xe8, 0xcd, 0x8f, 0xee, 0x34, 0x09, 0xae, 0xb2, 0xb7, 0x99, 0xbc, 0x97, 0xf7,
+	0x7e, 0x0c, 0x1c, 0xbd, 0xda, 0xca, 0xac, 0xac, 0x72, 0xa6, 0x5b, 0x3b, 0x55, 0x1a, 0xdb, 0xf9,
+	0x0e, 0x47, 0xa6, 0x96, 0xe7, 0xb0, 0xfb, 0xac, 0x9b, 0x47, 0xed, 0x3c, 0x22, 0x4c, 0x7a, 0xdd,
+	0xb8, 0x22, 0xbb, 0x18, 0x2f, 0x26, 0x14, 0x66, 0xf9, 0x00, 0x82, 0x94, 0xeb, 0x5b, 0x8f, 0x27,
+	0x20, 0x3e, 0xaa, 0xb6, 0x57, 0x51, 0x9f, 0x53, 0xda, 0xf0, 0x0a, 0x72, 0x76, 0xbe, 0x55, 0xde,
+	0xea, 0xcf, 0x62, 0xc4, 0xd2, 0x6c, 0x39, 0x2b, 0x4d, 0x5d, 0xa6, 0x54, 0xda, 0xa8, 0xf2, 0x12,
+	0xe6, 0xf7, 0x03, 0x06, 0xa9, 0x77, 0xfe, 0xe9, 0xf1, 0x18, 0xa6, 0x3c, 0xd8, 0x2f, 0x4e, 0xcc,
+	0x16, 0x39, 0xc5, 0x45, 0x7e, 0x67, 0xb0, 0x9f, 0x6c, 0x91, 0x16, 0xcf, 0x20, 0xaf, 0x3c, 0x27,
+	0xd4, 0xbd, 0x57, 0xc9, 0xbb, 0x79, 0x40, 0x09, 0xc2, 0x06, 0x44, 0x6e, 0xcf, 0xb8, 0x1d, 0x86,
+	0xf6, 0x08, 0x4d, 0x49, 0xc1, 0x6b, 0xd8, 0x7b, 0x59, 0xe9, 0xb6, 0xb1, 0x6a, 0x5d, 0x8c, 0x03,
+	0xe3, 0xe1, 0xe0, 0xfa, 0x57, 0x43, 0xbf, 0x96, 0xe5, 0x2d, 0x88, 0xbb, 0xa0, 0x61, 0x09, 0xd3,
+	0xa7, 0x81, 0x0a, 0x0f, 0xfe, 0xf8, 0x03, 0xfd, 0xe9, 0x76, 0x82, 0xdc, 0xa9, 0x45, 0xb8, 0xec,
+	0xcd, 0x4f, 0x00, 0x00, 0x00, 0xff, 0xff, 0xd9, 0x42, 0x7b, 0x6e, 0x70, 0x01, 0x00, 0x00,
+}

query/pb/graphresponse.proto

+syntax="proto3";
+package pb;
+
+service DGraph {
+  rpc Query (GraphRequest) returns (GraphResponse) {}
+}
+
+message UidList {
+  repeated uint64 uids = 1;
+}
+
+message Result {
+  repeated bytes values = 1;
+  repeated UidList uidmatrix = 2;
+}
+
+message GraphRequest {
+  string query = 1;
+}
+
+message GraphResponse {
+  string attribute = 1;
+  Result result = 2;
+  repeated GraphResponse children = 3; // Each node can have multiple children
+}

query/query.go

@@ -26,6 +26,7 @@ import (
 	"github.com/Sirupsen/logrus"
 	"github.com/dgraph-io/dgraph/gql"
 	"github.com/dgraph-io/dgraph/posting"
+	"github.com/dgraph-io/dgraph/query/pb"
 	"github.com/dgraph-io/dgraph/task"
 	"github.com/dgraph-io/dgraph/worker"
 	"github.com/dgraph-io/dgraph/x"
@@ -251,6 +252,75 @@ func (g *SubGraph) ToJson(l *Latency) (js []byte, rerr error) {
 	return json.Marshal(r)
 }
 
+// This method take in a flatbuffer result, extracts values and uids from it
+// and converts it to a protocol buffer result
+func extract(r *task.Result) (*pb.Result, error) {
+	var result = &pb.Result{}
+	var ul task.UidList
+	for i := 0; i < r.UidmatrixLength(); i++ {
+		if ok := r.Uidmatrix(&ul, i); !ok {
+			return result, fmt.Errorf("While parsing UidList")
+		}
+
+		uidList := &pb.UidList{}
+		for j := 0; j < ul.UidsLength(); j++ {
+			uid := ul.Uids(j)
+			uidList.Uids = append(uidList.Uids, uid)
+		}
+		result.Uidmatrix = append(result.Uidmatrix, uidList)
+	}
+
+	var tv task.Value
+	for i := 0; i < r.ValuesLength(); i++ {
+		if ok := r.Values(&tv, i); !ok {
+			return result, fmt.Errorf("While parsing value")
+		}
+
+		var ival interface{}
+		if err := posting.ParseValue(&ival, tv.ValBytes()); err != nil {
+			return result, err
+		}
+
+		if ival == nil {
+			ival = ""
+		}
+		result.Values = append(result.Values, []byte(ival.(string)))
+	}
+	return result, nil
+}
+
+// This method performs a pre traversal on a subgraph and converts it to a
+// protocol buffer Graph Response.
+func (g *SubGraph) PreTraverse() (gr *pb.GraphResponse, rerr error) {
+	gr = &pb.GraphResponse{}
+	if len(g.query) == 0 {
+		return gr, nil
+	}
+
+	gr.Attribute = g.Attr
+	ro := flatbuffers.GetUOffsetT(g.result)
+	r := new(task.Result)
+	r.Init(g.result, ro)
+
+	result, err := extract(r)
+	if err != nil {
+		return gr, err
+	}
+
+	gr.Result = result
+
+	for _, child := range g.Children {
+		childPb, err := child.PreTraverse()
+		if err != nil {
+			x.Err(glog, err).Error("Error while traversal")
+			return gr, err
+		}
+
+		gr.Children = append(gr.Children, childPb)
+	}
+	return gr, nil
+}
+
 func treeCopy(gq *gql.GraphQuery, sg *SubGraph) {
 	for _, gchild := range gq.Children {
 		dst := new(SubGraph)

query/query_test.go

@@ -319,3 +319,75 @@ func TestToJson(t *testing.T) {
 	}
 	fmt.Printf(string(js))
 }
+
+func TestPreTraverse(t *testing.T) {
+	dir, _ := populateGraph(t)
+	defer os.RemoveAll(dir)
+
+	query := `
+		{
+			me(_uid_:0x01) {
+				name
+				gender
+				status
+				friend {
+					name
+				}
+			}
+		}
+	`
+
+	gq, _, err := gql.Parse(query)
+	if err != nil {
+		t.Error(err)
+	}
+	sg, err := ToSubGraph(gq)
+	if err != nil {
+		t.Error(err)
+	}
+
+	ch := make(chan error)
+	go ProcessGraph(sg, ch)
+	err = <-ch
+	if err != nil {
+		t.Error(err)
+	}
+
+	ugr, err := sg.PreTraverse()
+	if err != nil {
+		t.Error(err)
+	}
+
+	if len(ugr.Children) != 4 {
+		t.Errorf("Expected len 4. Got: %v", ugr.Children)
+	}
+	child := ugr.Children[0]
+	if child.Attribute != "name" {
+		t.Errorf("Expected attr name. Got: %v", child.Attribute)
+	}
+	if string(child.Result.Values[0]) != "Michonne" {
+		t.Errorf("Expected value Michonne. Got %v",
+			string(child.Result.Values[0]))
+	}
+	child = ugr.Children[3]
+	if child.Attribute != "friend" {
+		t.Errorf("Expected attr friend. Got: %v", child.Attribute)
+	}
+	uids := child.Result.Uidmatrix[0].Uids
+	if uids[0] != 23 || uids[1] != 24 || uids[2] != 25 || uids[3] != 31 ||
+		uids[4] != 101 {
+		t.Errorf("Friend ids don't match")
+	}
+	// To check for name of friends
+	child = child.Children[0]
+	if child.Attribute != "name" {
+		t.Errorf("Expected attr friend. Got: %v", child.Attribute)
+	}
+
+	names := child.Result.Values
+
+	if string(names[0]) != "Rick Grimes" || string(names[1]) != "Glenn Rhee" ||
+		string(names[2]) != "Daryl Dixon" || string(names[3]) != "Andrea" {
+		t.Errorf("Names don't match")
+	}
+}

server/main.go

@@ -21,16 +21,22 @@ import (
 	"flag"
 	"fmt"
 	"io/ioutil"
+	"net"
 	"net/http"
 	"runtime"
 	"strings"
 	"time"
 
+	"golang.org/x/net/context"
+
+	"google.golang.org/grpc"
+
 	"github.com/Sirupsen/logrus"
 	"github.com/dgraph-io/dgraph/commit"
 	"github.com/dgraph-io/dgraph/gql"
 	"github.com/dgraph-io/dgraph/posting"
 	"github.com/dgraph-io/dgraph/query"
+	"github.com/dgraph-io/dgraph/query/pb"
 	"github.com/dgraph-io/dgraph/rdf"
 	"github.com/dgraph-io/dgraph/store"
 	"github.com/dgraph-io/dgraph/uid"
@@ -43,7 +49,7 @@ var glog = x.Log("server")
 var postingDir = flag.String("postings", "", "Directory to store posting lists")
 var uidDir = flag.String("uids", "", "XID UID posting lists directory")
 var mutationDir = flag.String("mutations", "", "Directory to store mutations")
-var port = flag.String("port", "8080", "Port to run server on.")
+var port = flag.Int("port", 8080, "Port to run server on.")
 var numcpu = flag.Int("numCpu", runtime.NumCPU(),
 	"Number of cores to be used by the process")
 var instanceIdx = flag.Uint64("instanceIdx", 0,
@@ -197,6 +203,71 @@ func queryHandler(w http.ResponseWriter, r *http.Request) {
 	fmt.Fprint(w, string(js))
 }
 
+// server is used to implement pb.DGraphServer
+type server struct{}
+
+// This method is used to execute the query and return the response to the
+// client as a protocol buffer message.
+func (s *server) Query(ctx context.Context,
+	req *pb.GraphRequest) (*pb.GraphResponse, error) {
+	resp := new(pb.GraphResponse)
+	if len(req.Query) == 0 {
+		glog.Error("While reading query")
+		return resp, fmt.Errorf("Empty query")
+	}
+
+	// TODO(pawan): Refactor query parsing and graph processing code to a common
+	// function used by Query and queryHandler
+	glog.WithField("q", req.Query).Debug("Query received.")
+	gq, _, err := gql.Parse(req.Query)
+	if err != nil {
+		x.Err(glog, err).Error("While parsing query")
+		return resp, err
+	}
+
+	sg, err := query.ToSubGraph(gq)
+	if err != nil {
+		x.Err(glog, err).Error("While conversion to internal format")
+		return resp, err
+	}
+	glog.WithField("q", req.Query).Debug("Query parsed.")
+
+	rch := make(chan error)
+	go query.ProcessGraph(sg, rch)
+	err = <-rch
+	if err != nil {
+		x.Err(glog, err).Error("While executing query")
+		return resp, err
+	}
+
+	glog.WithField("q", req.Query).Debug("Graph processed.")
+	resp, err = sg.PreTraverse()
+	if err != nil {
+		x.Err(glog, err).Error("While converting to protocol buffer.")
+		return resp, err
+	}
+
+	return resp, err
+}
+
+// This function register a DGraph grpc server on the address, which is used
+// exchanging protocol buffer messages.
+func runGrpcServer(address string) error {
+	ln, err := net.Listen("tcp", address)
+	if err != nil {
+		glog.Fatalf("While running server for client: %v", err)
+		return err
+	}
+	glog.WithField("address", ln.Addr()).Info("Client Worker listening")
+
+	s := grpc.NewServer()
+	pb.RegisterDGraphServer(s, &server{})
+	if err = s.Serve(ln); err != nil {
+		glog.Fatalf("While serving gRpc requests", err)
+	}
+	return nil
+}
+
 func main() {
 	flag.Parse()
 	if !flag.Parsed() {
@@ -205,9 +276,11 @@ func main() {
 	logrus.SetLevel(logrus.InfoLevel)
 	numCpus := *numcpu
 	prev := runtime.GOMAXPROCS(numCpus)
-	glog.WithField("num_cpu", numCpus).
-		WithField("prev_maxprocs", prev).
+	glog.WithField("num_cpu", numCpus).WithField("prev_maxprocs", prev).
 		Info("Set max procs to num cpus")
+	if *port%2 != 0 {
+		glog.Fatalf("Port should be an even number: %v", *port)
+	}
 
 	ps := new(store.Store)
 	ps.Init(*postingDir)
@@ -226,7 +299,6 @@ func main() {
 	}
 
 	posting.Init(clog)
-
 	if *instanceIdx != 0 {
 		worker.Init(ps, nil, *instanceIdx, lenAddr)
 		uid.Init(nil)
@@ -240,10 +312,12 @@ func main() {
 	}
 
 	worker.Connect(addrs)
+	// Grpc server runs on (port + 1)
+	runGrpcServer(fmt.Sprintf(":%d", *port+1))
 
 	http.HandleFunc("/query", queryHandler)
 	glog.WithField("port", *port).Info("Listening for requests...")
-	if err := http.ListenAndServe(":"+*port, nil); err != nil {
+	if err := http.ListenAndServe(fmt.Sprintf(":%d", *port), nil); err != nil {
 		x.Err(glog, err).Fatal("ListenAndServe")
 	}
 }

server/testrun.sh

 dir="/dgraph"
-go build . && ./server --instanceIdx 0 --mutations $dir/m0 --port "8080" --postings $dir/p0 --workers ":12345,:12346,:12347" --uids $dir/uasync.final --workerport ":12345" &
-go build . && ./server --instanceIdx 1 --mutations $dir/m1 --port "8081" --postings $dir/p1 --workers ":12345,:12346,:12347" --workerport ":12346" &
-go build . && ./server --instanceIdx 2 --mutations $dir/m2 --port "8082" --postings $dir/p2 --workers ":12345,:12346,:12347" --workerport ":12347" &
+go build . && ./server --instanceIdx 0 --mutations $dir/m0 --port 8080 --postings $dir/p0 --workers ":12345,:12346,:12347" --uids $dir/uasync.final --workerport ":12345" &
+go build . && ./server --instanceIdx 1 --mutations $dir/m1 --port 8082 --postings $dir/p1 --workers ":12345,:12346,:12347" --workerport ":12346" &
+go build . && ./server --instanceIdx 2 --mutations $dir/m2 --port 8084 --postings $dir/p2 --workers ":12345,:12346,:12347" --workerport ":12347" &