Merge master

auth/auth.go

@@ -42,7 +42,7 @@ type Auth interface {
 	// Revoke access to a resource
 	Revoke(rule *Rule) error
 	// Rules returns all the rules used to verify requests
-	Rules() ([]*Rule, error)
+	Rules(...RulesOption) ([]*Rule, error)
 	// String returns the name of the implementation
 	String() string
 }

auth/default.go

@@ -68,7 +68,7 @@ func (n *noop) Revoke(rule *Rule) error {
 }
 
 // Rules used to verify requests
-func (n *noop) Rules() ([]*Rule, error) {
+func (n *noop) Rules(opts ...RulesOption) ([]*Rule, error) {
 	return []*Rule{}, nil
 }
 

auth/jwt/jwt.go

@@ -105,7 +105,7 @@ func (j *jwt) Verify(acc *auth.Account, res *auth.Resource, opts ...auth.VerifyO
 	return rules.Verify(j.rules, acc, res)
 }
 
-func (j *jwt) Rules() ([]*auth.Rule, error) {
+func (j *jwt) Rules(opts ...auth.RulesOption) ([]*auth.Rule, error) {
 	j.Lock()
 	defer j.Unlock()
 	return j.rules, nil

auth/options.go

@@ -1,6 +1,7 @@
 package auth
 
 import (
+	"context"
 	"time"
 
 	"github.com/micro/go-micro/v2/auth/provider"
@@ -226,13 +227,25 @@ func NewTokenOptions(opts ...TokenOption) TokenOptions {
 }
 
 type VerifyOptions struct {
-	Namespace string
+	Context context.Context
 }
 
 type VerifyOption func(o *VerifyOptions)
 
-func VerifyNamespace(ns string) VerifyOption {
+func VerifyContext(ctx context.Context) VerifyOption {
 	return func(o *VerifyOptions) {
-		o.Namespace = ns
+		o.Context = ctx
+	}
+}
+
+type RulesOptions struct {
+	Context context.Context
+}
+
+type RulesOption func(o *RulesOptions)
+
+func RulesContext(ctx context.Context) RulesOption {
+	return func(o *RulesOptions) {
+		o.Context = ctx
 	}
 }

auth/service/service.go

@@ -3,7 +3,6 @@ package service
 import (
 	"context"
 	"strings"
-	"sync"
 	"time"
 
 	"github.com/micro/go-micro/v2/auth"
@@ -12,19 +11,14 @@ import (
 	"github.com/micro/go-micro/v2/auth/token"
 	"github.com/micro/go-micro/v2/auth/token/jwt"
 	"github.com/micro/go-micro/v2/client"
-	log "github.com/micro/go-micro/v2/logger"
-	"github.com/micro/go-micro/v2/metadata"
-	"github.com/micro/go-micro/v2/util/jitter"
 )
 
 // svc is the service implementation of the Auth interface
 type svc struct {
 	options auth.Options
 	auth    pb.AuthService
-	rule    pb.RulesService
+	rules   pb.RulesService
 	jwt     token.Provider
-	rules   map[string][]*auth.Rule
-	sync.Mutex
 }
 
 func (s *svc) String() string {
@@ -41,7 +35,7 @@ func (s *svc) Init(opts ...auth.Option) {
 	}
 
 	s.auth = pb.NewAuthService("go.micro.auth", s.options.Client)
-	s.rule = pb.NewRulesService("go.micro.auth", s.options.Client)
+	s.rules = pb.NewRulesService("go.micro.auth", s.options.Client)
 
 	// if we have a JWT public key passed as an option,
 	// we can decode tokens with the type "JWT" locally
@@ -52,8 +46,6 @@ func (s *svc) Init(opts ...auth.Option) {
 }
 
 func (s *svc) Options() auth.Options {
-	s.Lock()
-	defer s.Unlock()
 	return s.options
 }
 
@@ -85,7 +77,7 @@ func (s *svc) Grant(rule *auth.Rule) error {
 		access = pb.Access_DENIED
 	}
 
-	_, err := s.rule.Create(context.TODO(), &pb.CreateRequest{
+	_, err := s.rules.Create(context.TODO(), &pb.CreateRequest{
 		Rule: &pb.Rule{
 			Id:       rule.ID,
 			Scope:    rule.Scope,
@@ -99,25 +91,38 @@ func (s *svc) Grant(rule *auth.Rule) error {
 		},
 	})
 
-	if err == nil {
-		go s.loadRules(s.options.Namespace)
-	}
-
 	return err
 }
 
 // Revoke access to a resource
 func (s *svc) Revoke(rule *auth.Rule) error {
-	_, err := s.rule.Delete(context.TODO(), &pb.DeleteRequest{
+	_, err := s.rules.Delete(context.TODO(), &pb.DeleteRequest{
 		Id: rule.ID,
 	})
 
-	go s.loadRules(s.options.Namespace)
 	return err
 }
 
-func (s *svc) Rules() ([]*auth.Rule, error) {
+func (s *svc) Rules(opts ...auth.RulesOption) ([]*auth.Rule, error) {
-	return s.rules[s.options.Namespace], nil
+	var options auth.RulesOptions
+	for _, o := range opts {
+		o(&options)
+	}
+	if options.Context == nil {
+		options.Context = context.TODO()
+	}
+
+	rsp, err := s.rules.List(options.Context, &pb.ListRequest{})
+	if err != nil {
+		return nil, err
+	}
+
+	rules := make([]*auth.Rule, len(rsp.Rules))
+	for i, r := range rsp.Rules {
+		rules[i] = serializeRule(r)
+	}
+
+	return rules, nil
 }
 
 // Verify an account has access to a resource
@@ -126,15 +131,13 @@ func (s *svc) Verify(acc *auth.Account, res *auth.Resource, opts ...auth.VerifyO
 	for _, o := range opts {
 		o(&options)
 	}
-	if len(options.Namespace) == 0 {
+
-		options.Namespace = s.options.Namespace
+	rs, err := s.Rules(auth.RulesContext(options.Context))
+	if err != nil {
+		return err
 	}
 
-	// load the rules if none are loaded
+	return rules.Verify(rs, acc, res)
-	s.loadRulesIfEmpty(options.Namespace)
-
-	// verify the request using the rules
-	return rules.Verify(s.rules[options.Namespace], acc, res)
 }
 
 // Inspect a token
@@ -170,53 +173,6 @@ func (s *svc) Token(opts ...auth.TokenOption) (*auth.Token, error) {
 	return serializeToken(rsp.Token), nil
 }
 
-// loadRules retrieves the rules from the auth service. Since this implementation is used by micro
-// clients, which support muti-tenancy we may have to persist rules in multiple namespaces.
-func (s *svc) loadRules(namespace string) {
-	ctx := metadata.Set(context.TODO(), "Micro-Namespace", namespace)
-	rsp, err := s.rule.List(ctx, &pb.ListRequest{})
-	if err != nil {
-		log.Errorf("Error listing rules: %v", err)
-		return
-	}
-
-	rules := make([]*auth.Rule, 0, len(rsp.Rules))
-	for _, r := range rsp.Rules {
-		var access auth.Access
-		if r.Access == pb.Access_GRANTED {
-			access = auth.AccessGranted
-		} else {
-			access = auth.AccessDenied
-		}
-
-		rules = append(rules, &auth.Rule{
-			ID:       r.Id,
-			Scope:    r.Scope,
-			Access:   access,
-			Priority: r.Priority,
-			Resource: &auth.Resource{
-				Type:     r.Resource.Type,
-				Name:     r.Resource.Name,
-				Endpoint: r.Resource.Endpoint,
-			},
-		})
-	}
-
-	s.Lock()
-	s.rules[namespace] = rules
-	s.Unlock()
-}
-
-func (s *svc) loadRulesIfEmpty(namespace string) {
-	s.Lock()
-	rules := s.rules
-	s.Unlock()
-
-	if _, ok := rules[namespace]; !ok {
-		s.loadRules(namespace)
-	}
-}
-
 func serializeToken(t *pb.Token) *auth.Token {
 	return &auth.Token{
 		AccessToken:  t.AccessToken,
@@ -236,6 +192,27 @@ func serializeAccount(a *pb.Account) *auth.Account {
 	}
 }
 
+func serializeRule(r *pb.Rule) *auth.Rule {
+	var access auth.Access
+	if r.Access == pb.Access_GRANTED {
+		access = auth.AccessGranted
+	} else {
+		access = auth.AccessDenied
+	}
+
+	return &auth.Rule{
+		ID:       r.Id,
+		Scope:    r.Scope,
+		Access:   access,
+		Priority: r.Priority,
+		Resource: &auth.Resource{
+			Type:     r.Resource.Type,
+			Name:     r.Resource.Name,
+			Endpoint: r.Resource.Endpoint,
+		},
+	}
+}
+
 // NewAuth returns a new instance of the Auth service
 func NewAuth(opts ...auth.Option) auth.Auth {
 	options := auth.NewOptions(opts...)
@@ -243,26 +220,9 @@ func NewAuth(opts ...auth.Option) auth.Auth {
 		options.Client = client.DefaultClient
 	}
 
-	service := &svc{
+	return &svc{
 		auth:    pb.NewAuthService("go.micro.auth", options.Client),
-		rule:    pb.NewRulesService("go.micro.auth", options.Client),
+		rules:   pb.NewRulesService("go.micro.auth", options.Client),
-		rules:   make(map[string][]*auth.Rule),
 		options: options,
 	}
-
-	// load rules periodically from the auth service
-	go func() {
-		ruleTimer := time.NewTicker(time.Second * 30)
-
-		for {
-			<-ruleTimer.C
-			time.Sleep(jitter.Do(time.Second * 5))
-
-			for ns := range service.rules {
-				service.loadRules(ns)
-			}
-		}
-	}()
-
-	return service
 }

client/cache.go

@@ -0,0 +1,66 @@
+package client
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"hash/fnv"
+	"time"
+
+	"github.com/micro/go-micro/v2/metadata"
+	cache "github.com/patrickmn/go-cache"
+)
+
+// NewCache returns an initialised cache.
+func NewCache() *Cache {
+	return &Cache{
+		cache: cache.New(cache.NoExpiration, 30*time.Second),
+	}
+}
+
+// Cache for responses
+type Cache struct {
+	cache *cache.Cache
+}
+
+// Get a response from the cache
+func (c *Cache) Get(ctx context.Context, req *Request) (interface{}, bool) {
+	return c.cache.Get(key(ctx, req))
+}
+
+// Set a response in the cache
+func (c *Cache) Set(ctx context.Context, req *Request, rsp interface{}, expiry time.Duration) {
+	c.cache.Set(key(ctx, req), rsp, expiry)
+}
+
+// List the key value pairs in the cache
+func (c *Cache) List() map[string]string {
+	items := c.cache.Items()
+
+	rsp := make(map[string]string, len(items))
+	for k, v := range items {
+		bytes, _ := json.Marshal(v.Object)
+		rsp[k] = string(bytes)
+	}
+
+	return rsp
+}
+
+// key returns a hash for the context and request
+func key(ctx context.Context, req *Request) string {
+	md, _ := metadata.FromContext(ctx)
+
+	bytes, _ := json.Marshal(map[string]interface{}{
+		"metadata": md,
+		"request": map[string]interface{}{
+			"service":  (*req).Service(),
+			"endpoint": (*req).Endpoint(),
+			"method":   (*req).Method(),
+			"body":     (*req).Body(),
+		},
+	})
+
+	h := fnv.New64()
+	h.Write(bytes)
+	return fmt.Sprintf("%x", h.Sum(nil))
+}

client/cache_test.go

@@ -0,0 +1,76 @@
+package client
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/micro/go-micro/v2/metadata"
+)
+
+func TestCache(t *testing.T) {
+	ctx := context.TODO()
+	req := NewRequest("go.micro.service.foo", "Foo.Bar", nil)
+
+	t.Run("CacheMiss", func(t *testing.T) {
+		if _, ok := NewCache().Get(ctx, &req); ok {
+			t.Errorf("Expected to get no result from Get")
+		}
+	})
+
+	t.Run("CacheHit", func(t *testing.T) {
+		c := NewCache()
+
+		rsp := "theresponse"
+		c.Set(ctx, &req, rsp, time.Minute)
+
+		if res, ok := c.Get(ctx, &req); !ok {
+			t.Errorf("Expected a result, got nothing")
+		} else if res != rsp {
+			t.Errorf("Expected '%v' result, got '%v'", rsp, res)
+		}
+	})
+}
+
+func TestCacheKey(t *testing.T) {
+	ctx := context.TODO()
+	req1 := NewRequest("go.micro.service.foo", "Foo.Bar", nil)
+	req2 := NewRequest("go.micro.service.foo", "Foo.Baz", nil)
+	req3 := NewRequest("go.micro.service.foo", "Foo.Baz", "customquery")
+
+	t.Run("IdenticalRequests", func(t *testing.T) {
+		key1 := key(ctx, &req1)
+		key2 := key(ctx, &req1)
+		if key1 != key2 {
+			t.Errorf("Expected the keys to match for identical requests and context")
+		}
+	})
+
+	t.Run("DifferentRequestEndpoints", func(t *testing.T) {
+		key1 := key(ctx, &req1)
+		key2 := key(ctx, &req2)
+
+		if key1 == key2 {
+			t.Errorf("Expected the keys to differ for different request endpoints")
+		}
+	})
+
+	t.Run("DifferentRequestBody", func(t *testing.T) {
+		key1 := key(ctx, &req2)
+		key2 := key(ctx, &req3)
+
+		if key1 == key2 {
+			t.Errorf("Expected the keys to differ for different request bodies")
+		}
+	})
+
+	t.Run("DifferentMetadata", func(t *testing.T) {
+		mdCtx := metadata.Set(context.TODO(), "foo", "bar")
+		key1 := key(mdCtx, &req1)
+		key2 := key(ctx, &req1)
+
+		if key1 == key2 {
+			t.Errorf("Expected the keys to differ for different metadata")
+		}
+	})
+}

client/options.go

@@ -29,6 +29,9 @@ type Options struct {
 	PoolSize int
 	PoolTTL  time.Duration
 
+	// Response cache
+	Cache *Cache
+
 	// Middleware for client
 	Wrappers []Wrapper
 
@@ -59,6 +62,8 @@ type CallOptions struct {
 	StreamTimeout time.Duration
 	// Use the services own auth token
 	ServiceToken bool
+	// Duration to cache the response for
+	CacheExpiry time.Duration
 
 	// Middleware for low level call func
 	CallWrappers []CallWrapper
@@ -91,6 +96,7 @@ type RequestOptions struct {
 
 func NewOptions(options ...Option) Options {
 	opts := Options{
+		Cache:       NewCache(),
 		Context:     context.Background(),
 		ContentType: DefaultContentType,
 		Codecs:      make(map[string]codec.NewCodec),
@@ -324,6 +330,14 @@ func WithServiceToken() CallOption {
 	}
 }
 
+// WithCache is a CallOption which sets the duration the response
+// shoull be cached for
+func WithCache(c time.Duration) CallOption {
+	return func(o *CallOptions) {
+		o.CacheExpiry = c
+	}
+}
+
 func WithMessageContentType(ct string) MessageOption {
 	return func(o *MessageOptions) {
 		o.ContentType = ct

config/cmd/cmd.go

@@ -472,9 +472,13 @@ func (c *cmd) Before(ctx *cli.Context) error {
 	var serverOpts []server.Option
 	var clientOpts []client.Option
 
-	// setup a client to use when calling the runtime
+	// setup a client to use when calling the runtime. It is important the auth client is wrapped
+	// after the cache client since the wrappers are applied in reverse order and the cache will use
+	// some of the headers set by the auth client.
 	authFn := func() auth.Auth { return *c.opts.Auth }
-	microClient := wrapper.AuthClient(authFn, grpc.NewClient())
+	cacheFn := func() *client.Cache { return (*c.opts.Client).Options().Cache }
+	microClient := wrapper.CacheClient(cacheFn, grpc.NewClient())
+	microClient = wrapper.AuthClient(authFn, microClient)
 
 	// Set the store
 	if name := ctx.String("store"); len(name) > 0 {

debug/service/handler/debug.go

@@ -5,6 +5,7 @@ import (
 	"context"
 	"time"
 
+	"github.com/micro/go-micro/v2/client"
 	"github.com/micro/go-micro/v2/debug/log"
 	proto "github.com/micro/go-micro/v2/debug/service/proto"
 	"github.com/micro/go-micro/v2/debug/stats"
@@ -13,11 +14,12 @@ import (
 )
 
 // NewHandler returns an instance of the Debug Handler
-func NewHandler() *Debug {
+func NewHandler(c client.Client) *Debug {
 	return &Debug{
 		log:   log.DefaultLog,
 		stats: stats.DefaultStats,
 		trace: trace.DefaultTracer,
+		cache: c.Options().Cache,
 	}
 }
 
@@ -30,6 +32,8 @@ type Debug struct {
 	stats stats.Stats
 	// the tracer
 	trace trace.Tracer
+	// the cache
+	cache *client.Cache
 }
 
 func (d *Debug) Health(ctx context.Context, req *proto.HealthRequest, rsp *proto.HealthResponse) error {
@@ -164,3 +168,9 @@ func (d *Debug) Log(ctx context.Context, stream server.Stream) error {
 
 	return nil
 }
+
+// Cache returns all the key value pairs in the client cache
+func (d *Debug) Cache(ctx context.Context, req *proto.CacheRequest, rsp *proto.CacheResponse) error {
+	rsp.Values = d.cache.List()
+	return nil
+}

debug/service/proto/debug.pb.go

@@ -582,6 +582,76 @@ func (m *Span) GetType() SpanType {
 	return SpanType_INBOUND
 }
 
+type CacheRequest struct {
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *CacheRequest) Reset()         { *m = CacheRequest{} }
+func (m *CacheRequest) String() string { return proto.CompactTextString(m) }
+func (*CacheRequest) ProtoMessage()    {}
+func (*CacheRequest) Descriptor() ([]byte, []int) {
+	return fileDescriptor_df91f41a5db378e6, []int{9}
+}
+
+func (m *CacheRequest) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_CacheRequest.Unmarshal(m, b)
+}
+func (m *CacheRequest) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_CacheRequest.Marshal(b, m, deterministic)
+}
+func (m *CacheRequest) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_CacheRequest.Merge(m, src)
+}
+func (m *CacheRequest) XXX_Size() int {
+	return xxx_messageInfo_CacheRequest.Size(m)
+}
+func (m *CacheRequest) XXX_DiscardUnknown() {
+	xxx_messageInfo_CacheRequest.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_CacheRequest proto.InternalMessageInfo
+
+type CacheResponse struct {
+	Values               map[string]string `protobuf:"bytes,1,rep,name=values,proto3" json:"values,omitempty" protobuf_key:"bytes,1,opt,name=key,proto3" protobuf_val:"bytes,2,opt,name=value,proto3"`
+	XXX_NoUnkeyedLiteral struct{}          `json:"-"`
+	XXX_unrecognized     []byte            `json:"-"`
+	XXX_sizecache        int32             `json:"-"`
+}
+
+func (m *CacheResponse) Reset()         { *m = CacheResponse{} }
+func (m *CacheResponse) String() string { return proto.CompactTextString(m) }
+func (*CacheResponse) ProtoMessage()    {}
+func (*CacheResponse) Descriptor() ([]byte, []int) {
+	return fileDescriptor_df91f41a5db378e6, []int{10}
+}
+
+func (m *CacheResponse) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_CacheResponse.Unmarshal(m, b)
+}
+func (m *CacheResponse) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_CacheResponse.Marshal(b, m, deterministic)
+}
+func (m *CacheResponse) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_CacheResponse.Merge(m, src)
+}
+func (m *CacheResponse) XXX_Size() int {
+	return xxx_messageInfo_CacheResponse.Size(m)
+}
+func (m *CacheResponse) XXX_DiscardUnknown() {
+	xxx_messageInfo_CacheResponse.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_CacheResponse proto.InternalMessageInfo
+
+func (m *CacheResponse) GetValues() map[string]string {
+	if m != nil {
+		return m.Values
+	}
+	return nil
+}
+
 func init() {
 	proto.RegisterEnum("SpanType", SpanType_name, SpanType_value)
 	proto.RegisterType((*HealthRequest)(nil), "HealthRequest")
@@ -595,50 +665,56 @@ func init() {
 	proto.RegisterType((*TraceResponse)(nil), "TraceResponse")
 	proto.RegisterType((*Span)(nil), "Span")
 	proto.RegisterMapType((map[string]string)(nil), "Span.MetadataEntry")
+	proto.RegisterType((*CacheRequest)(nil), "CacheRequest")
+	proto.RegisterType((*CacheResponse)(nil), "CacheResponse")
+	proto.RegisterMapType((map[string]string)(nil), "CacheResponse.ValuesEntry")
 }
 
 func init() { proto.RegisterFile("debug/service/proto/debug.proto", fileDescriptor_df91f41a5db378e6) }
 
 var fileDescriptor_df91f41a5db378e6 = []byte{
-	// 594 bytes of a gzipped FileDescriptorProto
+	// 646 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xa4, 0x54, 0xdb, 0x6e, 0xd3, 0x40,
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xa4, 0x54, 0xdb, 0x6e, 0xd3, 0x4a,
-	0x10, 0x8d, 0xed, 0x38, 0xb1, 0xa7, 0x8d, 0xa9, 0x96, 0x8b, 0x2c, 0x73, 0x69, 0x65, 0x09, 0x29,
+	0x14, 0x8d, 0xed, 0x38, 0xb1, 0x77, 0x62, 0x9f, 0x6a, 0xce, 0x45, 0x96, 0x0f, 0xd0, 0xca, 0x12,
-	0x5c, 0xe4, 0x40, 0x79, 0x41, 0xf0, 0x86, 0x8a, 0x04, 0x52, 0x69, 0xa5, 0x6d, 0xfb, 0x01, 0x5b,
+	0x52, 0xb8, 0x68, 0x02, 0xe1, 0x85, 0xcb, 0x1b, 0x14, 0x09, 0xa4, 0xd2, 0x4a, 0xd3, 0x96, 0xf7,
-	0x7b, 0xe4, 0x1a, 0xea, 0x0b, 0xbb, 0xeb, 0x4a, 0xf9, 0x16, 0xbe, 0x80, 0x37, 0x7e, 0x86, 0xff,
+	0xa9, 0x3d, 0x4a, 0x03, 0xf5, 0x85, 0x99, 0x71, 0xa5, 0xbc, 0xf0, 0x23, 0xfc, 0x04, 0xff, 0x82,
-	0x41, 0x7b, 0x71, 0x1b, 0x0b, 0xa1, 0x3e, 0xf0, 0xb6, 0xe7, 0xec, 0xec, 0xc9, 0xcc, 0xc9, 0xf1,
+	0xf8, 0x1f, 0x34, 0x17, 0xb7, 0xb6, 0x10, 0xaa, 0x10, 0x6f, 0x5e, 0x6b, 0xaf, 0xd9, 0xd9, 0x7b,
-	0xc0, 0x6e, 0x81, 0xe7, 0x7d, 0xb9, 0x12, 0xc8, 0xaf, 0xaa, 0x1c, 0x57, 0x1d, 0x6f, 0x65, 0xbb,
+	0x69, 0x65, 0xc3, 0x6e, 0xc1, 0xce, 0xda, 0xf5, 0x52, 0x30, 0x7e, 0xb9, 0xc9, 0xd9, 0xb2, 0xe1,
-	0xd2, 0x5c, 0xa6, 0xcf, 0xe9, 0x33, 0x58, 0x7c, 0x42, 0x76, 0x29, 0x2f, 0x28, 0x7e, 0xef, 0x51,
+	0xb5, 0xac, 0x97, 0x9a, 0xc3, 0xfa, 0x3b, 0xbb, 0x07, 0xd1, 0x1b, 0x46, 0x2f, 0xe4, 0x39, 0x61,
-	0x48, 0x12, 0xc3, 0xdc, 0x56, 0xc7, 0xce, 0x9e, 0xb3, 0x0c, 0xe9, 0x00, 0xd3, 0x25, 0x44, 0x43,
+	0x9f, 0x5a, 0x26, 0x24, 0x4a, 0x60, 0x6a, 0xd5, 0x89, 0xb3, 0xe7, 0x2c, 0x42, 0xd2, 0xc1, 0x6c,
-	0xa9, 0xe8, 0xda, 0x46, 0x20, 0x79, 0x00, 0x33, 0x21, 0x99, 0xec, 0x85, 0x2d, 0xb5, 0x28, 0x5d,
+	0x01, 0x71, 0x27, 0x15, 0x4d, 0x5d, 0x09, 0x86, 0xfe, 0x83, 0x89, 0x90, 0x54, 0xb6, 0xc2, 0x4a,
-	0xc2, 0xf6, 0x89, 0x64, 0x52, 0xdc, 0xae, 0xf9, 0xdb, 0x81, 0x85, 0x2d, 0xb5, 0x9a, 0x8f, 0x20,
+	0x2d, 0xca, 0x16, 0x30, 0x3f, 0x96, 0x54, 0x8a, 0x9b, 0x7b, 0x7e, 0x77, 0x20, 0xb2, 0x52, 0xdb,
-	0x94, 0x55, 0x8d, 0x42, 0xb2, 0xba, 0xd3, 0xd5, 0x53, 0x7a, 0x43, 0x68, 0x25, 0xc9, 0xb8, 0xc4,
+	0xf3, 0x16, 0x84, 0x72, 0x53, 0x32, 0x21, 0x69, 0xd9, 0x68, 0xf5, 0x98, 0x5c, 0x13, 0xba, 0x93,
-	0x22, 0x76, 0xf5, 0xdd, 0x00, 0x55, 0x2f, 0x7d, 0xa7, 0x0a, 0x63, 0x4f, 0x5f, 0x58, 0xa4, 0xf8,
+	0xa4, 0x5c, 0xb2, 0x22, 0x71, 0x75, 0xad, 0x83, 0x6a, 0x96, 0xb6, 0x51, 0xc2, 0xc4, 0xd3, 0x05,
-	0x1a, 0xeb, 0x96, 0xaf, 0xe3, 0xa9, 0xe1, 0x0d, 0x52, 0x4a, 0xf2, 0x82, 0x23, 0x2b, 0x44, 0xec,
+	0x8b, 0x14, 0x5f, 0xb2, 0xb2, 0xe6, 0xdb, 0x64, 0x6c, 0x78, 0x83, 0x54, 0x27, 0x79, 0xce, 0x19,
-	0x1b, 0x25, 0x0b, 0x49, 0x04, 0x6e, 0x99, 0xc7, 0x33, 0x4d, 0xba, 0x65, 0x4e, 0x12, 0x08, 0xb8,
+	0x2d, 0x44, 0xe2, 0x9b, 0x4e, 0x16, 0xa2, 0x18, 0xdc, 0x75, 0x9e, 0x4c, 0x34, 0xe9, 0xae, 0x73,
-	0x19, 0x44, 0xc4, 0x73, 0xcd, 0x5e, 0x63, 0xa5, 0x8e, 0x9c, 0xb7, 0x5c, 0xc4, 0x81, 0x51, 0x37,
+	0x94, 0x42, 0xc0, 0xcd, 0x22, 0x22, 0x99, 0x6a, 0xf6, 0x0a, 0xab, 0xee, 0x8c, 0xf3, 0x9a, 0x8b,
-	0x28, 0xfd, 0x0a, 0x70, 0xd8, 0x96, 0xb7, 0xce, 0x6f, 0x1c, 0xe4, 0xc8, 0x6a, 0x3d, 0x4e, 0x40,
+	0x24, 0x30, 0xdd, 0x0d, 0xca, 0x3e, 0x00, 0x1c, 0xd4, 0xeb, 0x1b, 0xf7, 0x37, 0x0e, 0x72, 0x46,
-	0x2d, 0x22, 0xf7, 0xc0, 0xcf, 0xdb, 0xbe, 0x91, 0x7a, 0x18, 0x8f, 0x1a, 0xa0, 0x58, 0x51, 0x35,
+	0x4b, 0xbd, 0x4e, 0x40, 0x2c, 0x42, 0xff, 0x80, 0x9f, 0xd7, 0x6d, 0x25, 0xf5, 0x32, 0x1e, 0x31,
-	0x39, 0xea, 0x51, 0x3c, 0x6a, 0x40, 0xfa, 0xcb, 0x81, 0x19, 0xc5, 0xbc, 0xe5, 0xc5, 0xdf, 0xe6,
+	0x40, 0xb1, 0x62, 0x53, 0xe5, 0x4c, 0xaf, 0xe2, 0x11, 0x03, 0xb2, 0xaf, 0x0e, 0x4c, 0x08, 0xcb,
-	0x79, 0x9b, 0xe6, 0xbd, 0x86, 0xa0, 0x46, 0xc9, 0x0a, 0x26, 0x59, 0xec, 0xee, 0x79, 0xcb, 0xad,
+	0x6b, 0x5e, 0xfc, 0x6c, 0x9e, 0xd7, 0x37, 0xef, 0x31, 0x04, 0x25, 0x93, 0xb4, 0xa0, 0x92, 0x26,
-	0xfd, 0xfb, 0x99, 0x79, 0x98, 0x7d, 0xb1, 0xfc, 0xc7, 0x46, 0xf2, 0x35, 0xbd, 0x2e, 0x53, 0x9d,
+	0xee, 0x9e, 0xb7, 0x98, 0xad, 0xfe, 0xc5, 0xe6, 0x21, 0x7e, 0x67, 0xf9, 0xd7, 0x95, 0xe4, 0x5b,
-	0xd7, 0x28, 0x04, 0x2b, 0x8d, 0xad, 0x21, 0x1d, 0x60, 0xf2, 0x1e, 0x16, 0xa3, 0x47, 0x64, 0x07,
+	0x72, 0x25, 0x53, 0x93, 0x97, 0x4c, 0x08, 0xba, 0x36, 0xb6, 0x86, 0xa4, 0x83, 0xe9, 0x0b, 0x88,
-	0xbc, 0x6f, 0xb8, 0xb6, 0x03, 0xaa, 0xa3, 0x6a, 0xf7, 0x8a, 0x5d, 0xf6, 0xa8, 0x67, 0x0b, 0xa9,
+	0x06, 0x8f, 0xd0, 0x0e, 0x78, 0x1f, 0xd9, 0xd6, 0x2e, 0xa8, 0x3e, 0xd5, 0xb8, 0x97, 0xf4, 0xa2,
-	0x01, 0xef, 0xdc, 0xb7, 0x4e, 0xfa, 0x04, 0xb6, 0x4f, 0x39, 0xcb, 0x71, 0x30, 0x28, 0x02, 0xb7,
+	0x65, 0x7a, 0xb7, 0x90, 0x18, 0xf0, 0xdc, 0x7d, 0xea, 0x64, 0x77, 0x60, 0x7e, 0xc2, 0x69, 0xce,
-	0x2a, 0xec, 0x53, 0xb7, 0x2a, 0xd2, 0x97, 0xb0, 0xb0, 0xf7, 0x36, 0x15, 0x0f, 0xc1, 0x17, 0x1d,
+	0x3a, 0x83, 0x62, 0x70, 0x37, 0x85, 0x7d, 0xea, 0x6e, 0x8a, 0xec, 0x21, 0x44, 0xb6, 0x6e, 0x53,
-	0x6b, 0x54, 0xd0, 0x54, 0xdf, 0x7e, 0x76, 0xd2, 0xb1, 0x86, 0x1a, 0x2e, 0xfd, 0xe1, 0xc2, 0x54,
+	0xf1, 0x3f, 0xf8, 0xa2, 0xa1, 0x95, 0x0a, 0x9a, 0x9a, 0xdb, 0xc7, 0xc7, 0x0d, 0xad, 0x88, 0xe1,
-	0x61, 0xf5, 0x83, 0x52, 0x3d, 0xb3, 0x4a, 0x06, 0x58, 0x71, 0x77, 0x10, 0x57, 0x9e, 0x77, 0x8c,
+	0xb2, 0x2f, 0x2e, 0x8c, 0x15, 0x56, 0x3f, 0x28, 0xd5, 0x33, 0xdb, 0xc9, 0x00, 0xdb, 0xdc, 0xed,
-	0xa3, 0x35, 0x37, 0xa4, 0x16, 0x11, 0x02, 0xd3, 0x86, 0xd5, 0xc6, 0xdc, 0x90, 0xea, 0xf3, 0x66,
+	0x9a, 0x2b, 0xcf, 0x1b, 0xca, 0x99, 0x35, 0x37, 0x24, 0x16, 0x21, 0x04, 0xe3, 0x8a, 0x96, 0xc6,
-	0xde, 0xfc, 0x71, 0xde, 0x12, 0x08, 0x8a, 0x9e, 0x33, 0x59, 0xb5, 0x8d, 0xcd, 0xca, 0x35, 0x26,
+	0xdc, 0x90, 0xe8, 0xef, 0x7e, 0xde, 0xfc, 0x61, 0xde, 0x52, 0x08, 0x8a, 0x96, 0x53, 0xb9, 0xa9,
-	0xab, 0x0d, 0xa3, 0xe7, 0xba, 0xe1, 0xbb, 0xba, 0xe1, 0x7f, 0xda, 0xfc, 0x18, 0xa6, 0x72, 0xdd,
+	0x2b, 0x9b, 0x95, 0x2b, 0x8c, 0x96, 0x3d, 0xa3, 0xa7, 0x7a, 0xe0, 0xbf, 0xf5, 0xc0, 0xbf, 0xb4,
-	0xa1, 0x0e, 0x51, 0xb4, 0x1f, 0xea, 0xe2, 0xd3, 0x75, 0x87, 0x54, 0xd3, 0xff, 0xe5, 0xf5, 0xf3,
+	0xf9, 0x36, 0x8c, 0xe5, 0xb6, 0x61, 0x3a, 0x44, 0xf1, 0x2a, 0xd4, 0xe2, 0x93, 0x6d, 0xc3, 0x88,
-	0xa7, 0x10, 0x0c, 0x72, 0x64, 0x0b, 0xe6, 0x9f, 0x8f, 0x3e, 0x1c, 0x9f, 0x1d, 0x1d, 0xec, 0x4c,
+	0xa6, 0xff, 0xcc, 0xeb, 0x18, 0xe6, 0xaf, 0x68, 0x7e, 0xde, 0x79, 0x9d, 0x7d, 0x86, 0xc8, 0x62,
-	0xc8, 0x36, 0x04, 0xc7, 0x67, 0xa7, 0x06, 0x39, 0xfb, 0x3f, 0x1d, 0xf0, 0x0f, 0xd4, 0x62, 0x20,
+	0xeb, 0xed, 0x0a, 0x26, 0x5a, 0xdd, 0x99, 0x9b, 0xe2, 0x41, 0x1d, 0xbf, 0xd7, 0x45, 0x33, 0xb2,
-	0xbb, 0xe0, 0x1d, 0xb6, 0x25, 0xd9, 0xca, 0x6e, 0x12, 0x9c, 0xcc, 0x6d, 0x50, 0xd2, 0xc9, 0x2b,
+	0x55, 0xa6, 0xcf, 0x60, 0xd6, 0xa3, 0x7f, 0x67, 0x9e, 0xfb, 0x77, 0x21, 0xe8, 0xd6, 0x43, 0x33,
-	0x87, 0xbc, 0x80, 0x99, 0x59, 0x04, 0x24, 0xca, 0x46, 0xcb, 0x23, 0xb9, 0x93, 0x8d, 0x37, 0x44,
+	0x98, 0xbe, 0x3d, 0x7c, 0x79, 0x74, 0x7a, 0xb8, 0xbf, 0x33, 0x42, 0x73, 0x08, 0x8e, 0x4e, 0x4f,
-	0x3a, 0x21, 0x4b, 0xf0, 0xf5, 0x07, 0x4e, 0x16, 0xd9, 0xe6, 0x4e, 0x48, 0xa2, 0x6c, 0xf4, 0xdd,
+	0x0c, 0x72, 0x56, 0xdf, 0x1c, 0xf0, 0xf7, 0xd5, 0xa1, 0x42, 0xbb, 0xe0, 0x1d, 0xd4, 0x6b, 0x34,
-	0x9b, 0x4a, 0xfd, 0xa7, 0x93, 0x45, 0xb6, 0x19, 0x8e, 0x24, 0xca, 0x46, 0x59, 0x48, 0x27, 0xe7,
+	0xc3, 0xd7, 0xff, 0xa8, 0x74, 0x6a, 0x83, 0x9b, 0x8d, 0x1e, 0x39, 0xe8, 0x01, 0x4c, 0xcc, 0x61,
-	0x33, 0xbd, 0xbb, 0xde, 0xfc, 0x09, 0x00, 0x00, 0xff, 0xff, 0x6e, 0x42, 0x7f, 0x05, 0xde, 0x04,
+	0x42, 0x31, 0x1e, 0x1c, 0xb3, 0xf4, 0x2f, 0x3c, 0xbc, 0x58, 0xd9, 0x08, 0x2d, 0xc0, 0xd7, 0x07,
-	0x00, 0x00,
+	0x07, 0x45, 0xb8, 0x7f, 0xa3, 0xd2, 0x18, 0x0f, 0xee, 0x90, 0x51, 0xea, 0x10, 0xa2, 0x08, 0xf7,
+	0xc3, 0x9a, 0xc6, 0x78, 0x90, 0x4d, 0xa3, 0xd4, 0x96, 0xa1, 0x08, 0xf7, 0xad, 0x4e, 0xe3, 0xa1,
+	0x93, 0xd9, 0xe8, 0x6c, 0xa2, 0xaf, 0xee, 0x93, 0x1f, 0x01, 0x00, 0x00, 0xff, 0xff, 0x22, 0x65,
+	0x99, 0x10, 0x98, 0x05, 0x00, 0x00,
 }
 
 // Reference imports to suppress errors if they are not otherwise used.
@@ -657,6 +733,7 @@ type DebugClient interface {
 	Health(ctx context.Context, in *HealthRequest, opts ...grpc.CallOption) (*HealthResponse, error)
 	Stats(ctx context.Context, in *StatsRequest, opts ...grpc.CallOption) (*StatsResponse, error)
 	Trace(ctx context.Context, in *TraceRequest, opts ...grpc.CallOption) (*TraceResponse, error)
+	Cache(ctx context.Context, in *CacheRequest, opts ...grpc.CallOption) (*CacheResponse, error)
 }
 
 type debugClient struct {
@@ -726,12 +803,22 @@ func (c *debugClient) Trace(ctx context.Context, in *TraceRequest, opts ...grpc.
 	return out, nil
 }
 
+func (c *debugClient) Cache(ctx context.Context, in *CacheRequest, opts ...grpc.CallOption) (*CacheResponse, error) {
+	out := new(CacheResponse)
+	err := c.cc.Invoke(ctx, "/Debug/Cache", in, out, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
 // DebugServer is the server API for Debug service.
 type DebugServer interface {
 	Log(*LogRequest, Debug_LogServer) error
 	Health(context.Context, *HealthRequest) (*HealthResponse, error)
 	Stats(context.Context, *StatsRequest) (*StatsResponse, error)
 	Trace(context.Context, *TraceRequest) (*TraceResponse, error)
+	Cache(context.Context, *CacheRequest) (*CacheResponse, error)
 }
 
 // UnimplementedDebugServer can be embedded to have forward compatible implementations.
@@ -750,6 +837,9 @@ func (*UnimplementedDebugServer) Stats(ctx context.Context, req *StatsRequest) (
 func (*UnimplementedDebugServer) Trace(ctx context.Context, req *TraceRequest) (*TraceResponse, error) {
 	return nil, status.Errorf(codes.Unimplemented, "method Trace not implemented")
 }
+func (*UnimplementedDebugServer) Cache(ctx context.Context, req *CacheRequest) (*CacheResponse, error) {
+	return nil, status.Errorf(codes.Unimplemented, "method Cache not implemented")
+}
 
 func RegisterDebugServer(s *grpc.Server, srv DebugServer) {
 	s.RegisterService(&_Debug_serviceDesc, srv)
@@ -830,6 +920,24 @@ func _Debug_Trace_Handler(srv interface{}, ctx context.Context, dec func(interfa
 	return interceptor(ctx, in, info, handler)
 }
 
+func _Debug_Cache_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
+	in := new(CacheRequest)
+	if err := dec(in); err != nil {
+		return nil, err
+	}
+	if interceptor == nil {
+		return srv.(DebugServer).Cache(ctx, in)
+	}
+	info := &grpc.UnaryServerInfo{
+		Server:     srv,
+		FullMethod: "/Debug/Cache",
+	}
+	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
+		return srv.(DebugServer).Cache(ctx, req.(*CacheRequest))
+	}
+	return interceptor(ctx, in, info, handler)
+}
+
 var _Debug_serviceDesc = grpc.ServiceDesc{
 	ServiceName: "Debug",
 	HandlerType: (*DebugServer)(nil),
@@ -846,6 +954,10 @@ var _Debug_serviceDesc = grpc.ServiceDesc{
 			MethodName: "Trace",
 			Handler:    _Debug_Trace_Handler,
 		},
+		{
+			MethodName: "Cache",
+			Handler:    _Debug_Cache_Handler,
+		},
 	},
 	Streams: []grpc.StreamDesc{
 		{

debug/service/proto/debug.pb.micro.go

@@ -46,6 +46,7 @@ type DebugService interface {
 	Health(ctx context.Context, in *HealthRequest, opts ...client.CallOption) (*HealthResponse, error)
 	Stats(ctx context.Context, in *StatsRequest, opts ...client.CallOption) (*StatsResponse, error)
 	Trace(ctx context.Context, in *TraceRequest, opts ...client.CallOption) (*TraceResponse, error)
+	Cache(ctx context.Context, in *CacheRequest, opts ...client.CallOption) (*CacheResponse, error)
 }
 
 type debugService struct {
@@ -139,6 +140,16 @@ func (c *debugService) Trace(ctx context.Context, in *TraceRequest, opts ...clie
 	return out, nil
 }
 
+func (c *debugService) Cache(ctx context.Context, in *CacheRequest, opts ...client.CallOption) (*CacheResponse, error) {
+	req := c.c.NewRequest(c.name, "Debug.Cache", in)
+	out := new(CacheResponse)
+	err := c.c.Call(ctx, req, out, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
 // Server API for Debug service
 
 type DebugHandler interface {
@@ -146,6 +157,7 @@ type DebugHandler interface {
 	Health(context.Context, *HealthRequest, *HealthResponse) error
 	Stats(context.Context, *StatsRequest, *StatsResponse) error
 	Trace(context.Context, *TraceRequest, *TraceResponse) error
+	Cache(context.Context, *CacheRequest, *CacheResponse) error
 }
 
 func RegisterDebugHandler(s server.Server, hdlr DebugHandler, opts ...server.HandlerOption) error {
@@ -154,6 +166,7 @@ func RegisterDebugHandler(s server.Server, hdlr DebugHandler, opts ...server.Han
 		Health(ctx context.Context, in *HealthRequest, out *HealthResponse) error
 		Stats(ctx context.Context, in *StatsRequest, out *StatsResponse) error
 		Trace(ctx context.Context, in *TraceRequest, out *TraceResponse) error
+		Cache(ctx context.Context, in *CacheRequest, out *CacheResponse) error
 	}
 	type Debug struct {
 		debug
@@ -217,3 +230,7 @@ func (h *debugHandler) Stats(ctx context.Context, in *StatsRequest, out *StatsRe
 func (h *debugHandler) Trace(ctx context.Context, in *TraceRequest, out *TraceResponse) error {
 	return h.DebugHandler.Trace(ctx, in, out)
 }
+
+func (h *debugHandler) Cache(ctx context.Context, in *CacheRequest, out *CacheResponse) error {
+	return h.DebugHandler.Cache(ctx, in, out)
+}

debug/service/proto/debug.proto

@@ -1,10 +1,11 @@
 syntax = "proto3";
 
 service Debug {
-        rpc Log(LogRequest) returns (stream Record) {};
+	rpc Log(LogRequest) returns (stream Record) {};
-        rpc Health(HealthRequest) returns (HealthResponse) {};
+	rpc Health(HealthRequest) returns (HealthResponse) {};
-        rpc Stats(StatsRequest) returns (StatsResponse) {};
+	rpc Stats(StatsRequest) returns (StatsResponse) {};
 	rpc Trace(TraceRequest) returns (TraceResponse) {};
+	rpc Cache(CacheRequest) returns (CacheResponse) {};
 }
 
 message HealthRequest {
@@ -97,3 +98,9 @@ message Span {
 	map<string,string> metadata = 7;
 	SpanType type = 8;
 }
+
+message CacheRequest {}
+
+message CacheResponse {
+	map<string, string> values = 1;
+}

service.go

@@ -35,13 +35,14 @@ func newService(opts ...Option) Service {
 	// service name
 	serviceName := options.Server.Options().Name
 
-	// authFn returns the auth, we pass as a function since auth
+	// we pass functions to the wrappers since the values can change during initialisation
-	// has not yet been set at this point.
 	authFn := func() auth.Auth { return options.Server.Options().Auth }
+	cacheFn := func() *client.Cache { return options.Client.Options().Cache }
 
 	// wrap client to inject From-Service header on any calls
 	options.Client = wrapper.FromService(serviceName, options.Client)
 	options.Client = wrapper.TraceCall(serviceName, trace.DefaultTracer, options.Client)
+	options.Client = wrapper.CacheClient(cacheFn, options.Client)
 	options.Client = wrapper.AuthClient(authFn, options.Client)
 
 	// wrap the server to provide handler stats
@@ -183,7 +184,7 @@ func (s *service) Run() error {
 	// register the debug handler
 	s.opts.Server.Handle(
 		s.opts.Server.NewHandler(
-			handler.NewHandler(),
+			handler.NewHandler(s.opts.Client),
 			server.InternalHandler(true),
 		),
 	)

util/mux/mux.go

@@ -5,6 +5,7 @@ import (
 	"context"
 	"sync"
 
+	"github.com/micro/go-micro/v2/client"
 	"github.com/micro/go-micro/v2/debug/service/handler"
 	"github.com/micro/go-micro/v2/proxy"
 	"github.com/micro/go-micro/v2/server"
@@ -42,7 +43,7 @@ func New(name string, p proxy.Proxy) *Server {
 		server.DefaultRouter.Handle(
 			// inject the debug handler
 			server.DefaultRouter.NewHandler(
-				handler.NewHandler(),
+				handler.NewHandler(client.DefaultClient),
 				server.InternalHandler(true),
 			),
 		)

util/wrapper/wrapper.go

@@ -2,6 +2,7 @@ package wrapper
 
 import (
 	"context"
+	"reflect"
 	"strings"
 
 	"github.com/micro/go-micro/v2/auth"
@@ -221,7 +222,7 @@ func AuthHandler(fn func() auth.Auth) server.HandlerWrapper {
 			}
 
 			// Verify the caller has access to the resource
-			err := a.Verify(account, res, auth.VerifyNamespace(ns))
+			err := a.Verify(account, res, auth.VerifyContext(ctx))
 			if err != nil && account != nil {
 				return errors.Forbidden(req.Service(), "Forbidden call made to %v:%v by %v", req.Service(), req.Endpoint(), account.ID)
 			} else if err != nil {
@@ -238,3 +239,55 @@ func AuthHandler(fn func() auth.Auth) server.HandlerWrapper {
 		}
 	}
 }
+
+type cacheWrapper struct {
+	cacheFn func() *client.Cache
+	client.Client
+}
+
+// Call executes the request. If the CacheExpiry option was set, the response will be cached using
+// a hash of the metadata and request as the key.
+func (c *cacheWrapper) Call(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error {
+	// parse the options
+	var options client.CallOptions
+	for _, o := range opts {
+		o(&options)
+	}
+
+	// if the client doesn't have a cacbe setup don't continue
+	cache := c.cacheFn()
+	if cache == nil {
+		return c.Client.Call(ctx, req, rsp, opts...)
+	}
+
+	// if the cache expiry is not set, execute the call without the cache
+	if options.CacheExpiry == 0 {
+		return c.Client.Call(ctx, req, rsp, opts...)
+	}
+
+	// if the response is nil don't call the cache since we can't assign the response
+	if rsp == nil {
+		return c.Client.Call(ctx, req, rsp, opts...)
+	}
+
+	// check to see if there is a response cached, if there is assign it
+	if r, ok := cache.Get(ctx, &req); ok {
+		val := reflect.ValueOf(rsp).Elem()
+		val.Set(reflect.ValueOf(r).Elem())
+		return nil
+	}
+
+	// don't cache the result if there was an error
+	if err := c.Client.Call(ctx, req, rsp, opts...); err != nil {
+		return err
+	}
+
+	// set the result in the cache
+	cache.Set(ctx, &req, rsp, options.CacheExpiry)
+	return nil
+}
+
+// CacheClient wraps requests with the cache wrapper
+func CacheClient(cacheFn func() *client.Cache, c client.Client) client.Client {
+	return &cacheWrapper{cacheFn, c}
+}

util/wrapper/wrapper_test.go

@@ -3,10 +3,13 @@ package wrapper
 import (
 	"context"
 	"net/http"
+	"reflect"
 	"testing"
+	"time"
 
 	"github.com/micro/go-micro/v2/auth"
 	"github.com/micro/go-micro/v2/errors"
+	"github.com/micro/go-micro/v2/client"
 	"github.com/micro/go-micro/v2/metadata"
 	"github.com/micro/go-micro/v2/server"
 )
@@ -358,6 +361,98 @@ func TestAuthHandler(t *testing.T) {
 		}
 		if !handlerCalled {
 			t.Errorf("Expected the handler be called")
+type testClient struct {
+	callCount int
+	callRsp   interface{}
+	client.Client
+}
+
+func (c *testClient) Call(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error {
+	c.callCount++
+
+	if c.callRsp != nil {
+		val := reflect.ValueOf(rsp).Elem()
+		val.Set(reflect.ValueOf(c.callRsp).Elem())
+	}
+
+	return nil
+}
+
+type testRsp struct {
+	value string
+}
+
+func TestCacheWrapper(t *testing.T) {
+	req := client.NewRequest("go.micro.service.foo", "Foo.Bar", nil)
+
+	t.Run("NilCache", func(t *testing.T) {
+		cli := new(testClient)
+
+		w := CacheClient(func() *client.Cache {
+			return nil
+		}, cli)
+
+		// perfroming two requests should increment the call count by two indicating the cache wasn't
+		// used even though the WithCache option was passed.
+		w.Call(context.TODO(), req, nil, client.WithCache(time.Minute))
+		w.Call(context.TODO(), req, nil, client.WithCache(time.Minute))
+
+		if cli.callCount != 2 {
+			t.Errorf("Expected the client to have been called twice")
+		}
+	})
+
+	t.Run("OptionNotSet", func(t *testing.T) {
+		cli := new(testClient)
+		cache := client.NewCache()
+
+		w := CacheClient(func() *client.Cache {
+			return cache
+		}, cli)
+
+		// perfroming two requests should increment the call count by two since we didn't pass the WithCache
+		// option to Call.
+		w.Call(context.TODO(), req, nil)
+		w.Call(context.TODO(), req, nil)
+
+		if cli.callCount != 2 {
+			t.Errorf("Expected the client to have been called twice")
+		}
+	})
+
+	t.Run("OptionSet", func(t *testing.T) {
+		val := "foo"
+		cli := &testClient{callRsp: &testRsp{value: val}}
+		cache := client.NewCache()
+
+		w := CacheClient(func() *client.Cache {
+			return cache
+		}, cli)
+
+		// perfroming two requests should increment the call count by once since the second request should
+		// have used the cache. The correct value should be set on both responses and no errors should
+		// be returned.
+		rsp1 := &testRsp{}
+		rsp2 := &testRsp{}
+		err1 := w.Call(context.TODO(), req, rsp1, client.WithCache(time.Minute))
+		err2 := w.Call(context.TODO(), req, rsp2, client.WithCache(time.Minute))
+
+		if err1 != nil {
+			t.Errorf("Expected nil error, got %v", err1)
+		}
+		if err2 != nil {
+			t.Errorf("Expected nil error, got %v", err2)
+		}
+
+		if rsp1.value != val {
+			t.Errorf("Expected %v to be assigned to the value, got %v", val, rsp1.value)
+		}
+		if rsp2.value != val {
+			t.Errorf("Expected %v to be assigned to the value, got %v", val, rsp2.value)
+		}
+
+		if cli.callCount != 1 {
+			t.Errorf("Expected the client to be called 1 time, was actually called %v time(s)", cli.callCount)
 		}
 	})
 }