Deprecate client/selector (#1767)

* client/{grpc,rpc}: depricate selector (wip)

* {client,cmd}: remove client/selector

* deprecate client/selector

* router/static: fix lookup

* config/cmd: add support for legacy static selector flag

* config/cmd: add support for legacy dns selector flag

api/handler/api/api.go

@@ -6,9 +6,9 @@ import (
 
 	goapi "github.com/micro/go-micro/v2/api"
 	"github.com/micro/go-micro/v2/api/handler"
+	"github.com/micro/go-micro/v2/api/handler/util"
 	api "github.com/micro/go-micro/v2/api/proto"
 	"github.com/micro/go-micro/v2/client"
-	"github.com/micro/go-micro/v2/client/selector"
 	"github.com/micro/go-micro/v2/errors"
 	"github.com/micro/go-micro/v2/util/ctx"
 )
@@ -71,10 +71,8 @@ func (a *apiHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 
 	// create the context from headers
 	cx := ctx.FromRequest(r)
-	// create strategy
-	so := selector.WithStrategy(strategy(service.Services))
 
-	if err := c.Call(cx, req, rsp, client.WithSelectOption(so)); err != nil {
+	if err := c.Call(cx, req, rsp, client.WithRouter(util.Router(service.Services))); err != nil {
 		w.Header().Set("Content-Type", "application/json")
 		ce := errors.Parse(err.Error())
 		switch ce.Code {

api/handler/api/util.go

@@ -8,8 +8,6 @@ import (
 	"strings"
 
 	api "github.com/micro/go-micro/v2/api/proto"
-	"github.com/micro/go-micro/v2/client/selector"
-	"github.com/micro/go-micro/v2/registry"
 	"github.com/oxtoacart/bpool"
 )
 
@@ -109,11 +107,3 @@ func requestToProto(r *http.Request) (*api.Request, error) {
 
 	return req, nil
 }
-
-// strategy is a hack for selection
-func strategy(services []*registry.Service) selector.Strategy {
-	return func(_ []*registry.Service) selector.Next {
-		// ignore input to this function, use services above
-		return selector.Random(services)
-	}
-}

api/handler/http/http.go

@@ -4,13 +4,14 @@ package http
 import (
 	"errors"
 	"fmt"
+	"math/rand"
 	"net/http"
 	"net/http/httputil"
 	"net/url"
 
 	"github.com/micro/go-micro/v2/api"
 	"github.com/micro/go-micro/v2/api/handler"
-	"github.com/micro/go-micro/v2/client/selector"
+	"github.com/micro/go-micro/v2/registry"
 )
 
 const (
@@ -64,16 +65,19 @@ func (h *httpHandler) getService(r *http.Request) (string, error) {
 		return "", errors.New("no route found")
 	}
 
-	// create a random selector
-	next := selector.Random(service.Services)
-
-	// get the next node
-	s, err := next()
-	if err != nil {
-		return "", nil
+	// get the nodes for this service
+	var nodes []*registry.Node
+	for _, srv := range service.Services {
+		nodes = append(nodes, srv.Nodes...)
 	}
 
-	return fmt.Sprintf("http://%s", s.Address), nil
+	// select a random node
+	if len(nodes) == 0 {
+		return "", errors.New("no route found")
+	}
+	node := nodes[rand.Int()%len(nodes)]
+
+	return fmt.Sprintf("http://%s", node.Address), nil
 }
 
 func (h *httpHandler) String() string {

api/handler/rpc/rpc.go

@@ -12,16 +12,15 @@ import (
 	jsonpatch "github.com/evanphx/json-patch/v5"
 	"github.com/micro/go-micro/v2/api"
 	"github.com/micro/go-micro/v2/api/handler"
+	"github.com/micro/go-micro/v2/api/handler/util"
 	"github.com/micro/go-micro/v2/api/internal/proto"
 	"github.com/micro/go-micro/v2/client"
-	"github.com/micro/go-micro/v2/client/selector"
 	"github.com/micro/go-micro/v2/codec"
 	"github.com/micro/go-micro/v2/codec/jsonrpc"
 	"github.com/micro/go-micro/v2/codec/protorpc"
 	"github.com/micro/go-micro/v2/errors"
 	"github.com/micro/go-micro/v2/logger"
 	"github.com/micro/go-micro/v2/metadata"
-	"github.com/micro/go-micro/v2/registry"
 	"github.com/micro/go-micro/v2/util/ctx"
 	"github.com/micro/go-micro/v2/util/qson"
 	"github.com/oxtoacart/bpool"
@@ -65,14 +64,6 @@ func (b *buffer) Write(_ []byte) (int, error) {
 	return 0, nil
 }
 
-// strategy is a hack for selection
-func strategy(services []*registry.Service) selector.Strategy {
-	return func(_ []*registry.Service) selector.Next {
-		// ignore input to this function, use services above
-		return selector.Random(services)
-	}
-}
-
 func (h *rpcHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	bsize := handler.DefaultMaxRecvSize
 	if h.opts.MaxRecvSize > 0 {
@@ -141,8 +132,8 @@ func (h *rpcHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	// create strategy
-	so := selector.WithStrategy(strategy(service.Services))
+	// create custom router
+	callOpt := client.WithRouter(util.Router(service.Services))
 
 	// walk the standard call path
 	// get payload
@@ -174,7 +165,7 @@ func (h *rpcHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		)
 
 		// make the call
-		if err := c.Call(cx, req, response, client.WithSelectOption(so)); err != nil {
+		if err := c.Call(cx, req, response, callOpt); err != nil {
 			writeError(w, r, err)
 			return
 		}
@@ -209,7 +200,7 @@ func (h *rpcHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 			client.WithContentType(ct),
 		)
 		// make the call
-		if err := c.Call(cx, req, &response, client.WithSelectOption(so)); err != nil {
+		if err := c.Call(cx, req, &response, callOpt); err != nil {
 			writeError(w, r, err)
 			return
 		}

api/handler/rpc/stream.go

@@ -13,8 +13,8 @@ import (
 	"github.com/gobwas/ws"
 	"github.com/gobwas/ws/wsutil"
 	"github.com/micro/go-micro/v2/api"
+	"github.com/micro/go-micro/v2/api/handler/util"
 	"github.com/micro/go-micro/v2/client"
-	"github.com/micro/go-micro/v2/client/selector"
 	raw "github.com/micro/go-micro/v2/codec/bytes"
 	"github.com/micro/go-micro/v2/logger"
 )
@@ -110,9 +110,11 @@ func serveWebsocket(ctx context.Context, w http.ResponseWriter, r *http.Request,
 		client.StreamingRequest(),
 	)
 
-	so := selector.WithStrategy(strategy(service.Services))
+	// create custom router
+	callOpt := client.WithRouter(util.Router(service.Services))
+
 	// create a new stream
-	stream, err := c.Stream(ctx, req, client.WithSelectOption(so))
+	stream, err := c.Stream(ctx, req, callOpt)
 	if err != nil {
 		if logger.V(logger.ErrorLevel, logger.DefaultLogger) {
 			logger.Error(err)

api/handler/util/router.go

@@ -0,0 +1,32 @@
+package util
+
+import (
+	"github.com/micro/go-micro/v2/registry"
+	"github.com/micro/go-micro/v2/router"
+)
+
+// Router is a hack for API routing
+func Router(srvs []*registry.Service) router.Router {
+	var routes []router.Route
+
+	for _, srv := range srvs {
+		for _, n := range srv.Nodes {
+			routes = append(routes, router.Route{Address: n.Address, Metadata: n.Metadata})
+		}
+	}
+
+	return &apiRouter{routes: routes}
+}
+
+func (r *apiRouter) Lookup(...router.QueryOption) ([]router.Route, error) {
+	return r.routes, nil
+}
+
+type apiRouter struct {
+	routes []router.Route
+	router.Router
+}
+
+func (r *apiRouter) String() string {
+	return "api"
+}

api/handler/web/web.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"math/rand"
 	"net"
 	"net/http"
 	"net/http/httputil"
@@ -13,7 +14,7 @@ import (
 
 	"github.com/micro/go-micro/v2/api"
 	"github.com/micro/go-micro/v2/api/handler"
-	"github.com/micro/go-micro/v2/client/selector"
+	"github.com/micro/go-micro/v2/registry"
 )
 
 const (
@@ -70,16 +71,19 @@ func (wh *webHandler) getService(r *http.Request) (string, error) {
 		return "", errors.New("no route found")
 	}
 
-	// create a random selector
-	next := selector.Random(service.Services)
-
-	// get the next node
-	s, err := next()
-	if err != nil {
-		return "", nil
+	// get the nodes
+	var nodes []*registry.Node
+	for _, srv := range service.Services {
+		nodes = append(nodes, srv.Nodes...)
+	}
+	if len(nodes) == 0 {
+		return "", errors.New("no route found")
 	}
 
-	return fmt.Sprintf("http://%s", s.Address), nil
+	// select a random node
+	node := nodes[rand.Int()%len(nodes)]
+
+	return fmt.Sprintf("http://%s", node.Address), nil
 }
 
 // serveWebSocket used to serve a web socket proxied connection