rename rpcx to zrpc

zrpc/internal/resolver/directbuilder.go

@@ -0,0 +1,32 @@
+package resolver
+
+import (
+	"strings"
+
+	"google.golang.org/grpc/resolver"
+)
+
+type directBuilder struct{}
+
+func (d *directBuilder) Build(target resolver.Target, cc resolver.ClientConn, opts resolver.BuildOptions) (
+	resolver.Resolver, error) {
+	var addrs []resolver.Address
+	endpoints := strings.FieldsFunc(target.Endpoint, func(r rune) bool {
+		return r == EndpointSepChar
+	})
+
+	for _, val := range subset(endpoints, subsetSize) {
+		addrs = append(addrs, resolver.Address{
+			Addr: val,
+		})
+	}
+	cc.UpdateState(resolver.State{
+		Addresses: addrs,
+	})
+
+	return &nopResolver{cc: cc}, nil
+}
+
+func (d *directBuilder) Scheme() string {
+	return DirectScheme
+}

zrpc/internal/resolver/directbuilder_test.go

@@ -0,0 +1,52 @@
+package resolver
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/tal-tech/go-zero/core/lang"
+	"github.com/tal-tech/go-zero/core/mathx"
+	"google.golang.org/grpc/resolver"
+)
+
+func TestDirectBuilder_Build(t *testing.T) {
+	tests := []int{
+		0,
+		1,
+		2,
+		subsetSize / 2,
+		subsetSize,
+		subsetSize * 2,
+	}
+
+	for _, test := range tests {
+		t.Run(strconv.Itoa(test), func(t *testing.T) {
+			var servers []string
+			for i := 0; i < test; i++ {
+				servers = append(servers, fmt.Sprintf("localhost:%d", i))
+			}
+			var b directBuilder
+			cc := new(mockedClientConn)
+			_, err := b.Build(resolver.Target{
+				Scheme:   DirectScheme,
+				Endpoint: strings.Join(servers, ","),
+			}, cc, resolver.BuildOptions{})
+			assert.Nil(t, err)
+			size := mathx.MinInt(test, subsetSize)
+			assert.Equal(t, size, len(cc.state.Addresses))
+			m := make(map[string]lang.PlaceholderType)
+			for _, each := range cc.state.Addresses {
+				m[each.Addr] = lang.Placeholder
+			}
+			assert.Equal(t, size, len(m))
+		})
+	}
+}
+
+func TestDirectBuilder_Scheme(t *testing.T) {
+	var b directBuilder
+	assert.Equal(t, DirectScheme, b.Scheme())
+}

zrpc/internal/resolver/discovbuilder.go

@@ -0,0 +1,41 @@
+package resolver
+
+import (
+	"strings"
+
+	"github.com/tal-tech/go-zero/core/discov"
+	"google.golang.org/grpc/resolver"
+)
+
+type discovBuilder struct{}
+
+func (d *discovBuilder) Build(target resolver.Target, cc resolver.ClientConn, opts resolver.BuildOptions) (
+	resolver.Resolver, error) {
+	hosts := strings.FieldsFunc(target.Authority, func(r rune) bool {
+		return r == EndpointSepChar
+	})
+	sub, err := discov.NewSubscriber(hosts, target.Endpoint)
+	if err != nil {
+		return nil, err
+	}
+
+	update := func() {
+		var addrs []resolver.Address
+		for _, val := range subset(sub.Values(), subsetSize) {
+			addrs = append(addrs, resolver.Address{
+				Addr: val,
+			})
+		}
+		cc.UpdateState(resolver.State{
+			Addresses: addrs,
+		})
+	}
+	sub.AddListener(update)
+	update()
+
+	return &nopResolver{cc: cc}, nil
+}
+
+func (d *discovBuilder) Scheme() string {
+	return DiscovScheme
+}

zrpc/internal/resolver/resolver.go

@@ -0,0 +1,35 @@
+package resolver
+
+import (
+	"fmt"
+
+	"google.golang.org/grpc/resolver"
+)
+
+const (
+	DirectScheme    = "direct"
+	DiscovScheme    = "discov"
+	EndpointSepChar = ','
+	subsetSize      = 32
+)
+
+var (
+	EndpointSep = fmt.Sprintf("%c", EndpointSepChar)
+	dirBuilder  directBuilder
+	disBuilder  discovBuilder
+)
+
+func RegisterResolver() {
+	resolver.Register(&dirBuilder)
+	resolver.Register(&disBuilder)
+}
+
+type nopResolver struct {
+	cc resolver.ClientConn
+}
+
+func (r *nopResolver) Close() {
+}
+
+func (r *nopResolver) ResolveNow(options resolver.ResolveNowOptions) {
+}

zrpc/internal/resolver/resolver_test.go

@@ -0,0 +1,36 @@
+package resolver
+
+import (
+	"testing"
+
+	"google.golang.org/grpc/resolver"
+	"google.golang.org/grpc/serviceconfig"
+)
+
+func TestNopResolver(t *testing.T) {
+	// make sure ResolveNow & Close don't panic
+	var r nopResolver
+	r.ResolveNow(resolver.ResolveNowOptions{})
+	r.Close()
+}
+
+type mockedClientConn struct {
+	state resolver.State
+}
+
+func (m *mockedClientConn) UpdateState(state resolver.State) {
+	m.state = state
+}
+
+func (m *mockedClientConn) ReportError(err error) {
+}
+
+func (m *mockedClientConn) NewAddress(addresses []resolver.Address) {
+}
+
+func (m *mockedClientConn) NewServiceConfig(serviceConfig string) {
+}
+
+func (m *mockedClientConn) ParseServiceConfig(serviceConfigJSON string) *serviceconfig.ParseResult {
+	return nil
+}

zrpc/internal/resolver/subset.go

@@ -0,0 +1,14 @@
+package resolver
+
+import "math/rand"
+
+func subset(set []string, sub int) []string {
+	rand.Shuffle(len(set), func(i, j int) {
+		set[i], set[j] = set[j], set[i]
+	})
+	if len(set) <= sub {
+		return set
+	} else {
+		return set[:sub]
+	}
+}

zrpc/internal/resolver/subset_test.go

@@ -0,0 +1,53 @@
+package resolver
+
+import (
+	"strconv"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/tal-tech/go-zero/core/mathx"
+)
+
+func TestSubset(t *testing.T) {
+	tests := []struct {
+		name string
+		set  int
+		sub  int
+	}{
+		{
+			name: "more vals to subset",
+			set:  100,
+			sub:  36,
+		},
+		{
+			name: "less vals to subset",
+			set:  100,
+			sub:  200,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			var vals []string
+			for i := 0; i < test.set; i++ {
+				vals = append(vals, strconv.Itoa(i))
+			}
+
+			m := make(map[interface{}]int)
+			for i := 0; i < 1000; i++ {
+				set := subset(append([]string(nil), vals...), test.sub)
+				if test.sub < test.set {
+					assert.Equal(t, test.sub, len(set))
+				} else {
+					assert.Equal(t, test.set, len(set))
+				}
+
+				for _, val := range set {
+					m[val]++
+				}
+			}
+
+			assert.True(t, mathx.CalcEntropy(m) > 0.95)
+		})
+	}
+}