meter/handler: more idiomatic option handling

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

go.sum

@@ -10,6 +10,7 @@ github.com/patrickmn/go-cache v2.1.0+incompatible h1:HRMgzkcYKYpi3C8ajMPV8OFXaaR
 github.com/patrickmn/go-cache v2.1.0+incompatible/go.mod h1:3Qf8kWWT7OJRJbdiICTKqZju1ZixQ/KpMGzzAfe6+WQ=
 github.com/silas/dag v0.0.0-20210121180416-41cf55125c34 h1:vBfVmA5mZhsQa2jr1FOL9nfA37N/jnbBmi5XUfviVTI=
 github.com/silas/dag v0.0.0-20210121180416-41cf55125c34/go.mod h1:7RTUFBdIRC9nZ7/3RyRNH1bdqIShrDejd1YbLwgPS+I=
+golang.org/x/net v0.0.0-20210326220855-61e056675ecf h1:WUcCxqQqDT0aXO4VnQbfMvp4zh7m1Gb2clVuHUAGGRE=
 golang.org/x/net v0.0.0-20210326220855-61e056675ecf/go.mod h1:uSPa2vr4CLtc/ILN5odXGNXS6mhrKVzTaCXzk9m6W3k=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210324051608-47abb6519492/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=

meter/handler/handler.go

@@ -5,6 +5,7 @@ import (
 	"context"
 
 	"github.com/unistack-org/micro/v3/codec"
+	"github.com/unistack-org/micro/v3/errors"
 	"github.com/unistack-org/micro/v3/meter"
 )
 
@@ -14,18 +15,52 @@ var (
 )
 
 type handler struct {
-	meter meter.Meter
-	opts  []meter.Option
+	opts Options
 }
 
-func NewHandler(meter meter.Meter, opts ...meter.Option) *handler {
-	return &handler{meter: meter, opts: opts}
+type Option func(*Options)
+
+type Options struct {
+	Meter        meter.Meter
+	MeterOptions []meter.Option
+	Name         string
+}
+
+func Meter(m meter.Meter) Option {
+	return func(o *Options) {
+		o.Meter = m
+	}
+}
+
+func Name(name string) Option {
+	return func(o *Options) {
+		o.Name = name
+	}
+}
+
+func MeterOptions(opts ...meter.Option) Option {
+	return func(o *Options) {
+		o.MeterOptions = append(o.MeterOptions, opts...)
+	}
+}
+
+func NewOptions(opts ...Option) Options {
+	options := Options{Meter: meter.DefaultMeter}
+	for _, o := range opts {
+		o(&options)
+	}
+	return options
+}
+
+func NewHandler(opts ...Option) *handler {
+	options := NewOptions(opts...)
+	return &handler{opts: options}
 }
 
 func (h *handler) Metrics(ctx context.Context, req *codec.Frame, rsp *codec.Frame) error {
 	buf := bytes.NewBuffer(nil)
-	if err := h.meter.Write(buf, h.opts...); err != nil {
-		return err
+	if err := h.opts.Meter.Write(buf, h.opts.MeterOptions...); err != nil {
+		return errors.InternalServerError(h.opts.Name, "%v", err)
 	}
 
 	rsp.Data = buf.Bytes()

service.go

@@ -103,48 +103,48 @@ func (s *service) Init(opts ...Option) error {
 			// skip config as the struct not passed
 			continue
 		}
-		if err = cfg.Init(config.Context(s.opts.Context)); err != nil {
+		if err = cfg.Init(config.Context(cfg.Options().Context)); err != nil {
 			return err
 		}
 
-		if err = cfg.Load(s.opts.Context); err != nil {
+		if err = cfg.Load(cfg.Options().Context); err != nil {
 			return err
 		}
 
 	}
 
 	for _, log := range s.opts.Loggers {
-		if err = log.Init(logger.WithContext(s.opts.Context)); err != nil {
+		if err = log.Init(logger.WithContext(log.Options().Context)); err != nil {
 			return err
 		}
 	}
 
 	for _, reg := range s.opts.Registers {
-		if err = reg.Init(register.Context(s.opts.Context)); err != nil {
+		if err = reg.Init(register.Context(reg.Options().Context)); err != nil {
 			return err
 		}
 	}
 
 	for _, brk := range s.opts.Brokers {
-		if err = brk.Init(broker.Context(s.opts.Context)); err != nil {
+		if err = brk.Init(broker.Context(brk.Options().Context)); err != nil {
 			return err
 		}
 	}
 
 	for _, str := range s.opts.Stores {
-		if err = str.Init(store.Context(s.opts.Context)); err != nil {
+		if err = str.Init(store.Context(str.Options().Context)); err != nil {
 			return err
 		}
 	}
 
 	for _, srv := range s.opts.Servers {
-		if err = srv.Init(server.Context(s.opts.Context)); err != nil {
+		if err = srv.Init(server.Context(srv.Options().Context)); err != nil {
 			return err
 		}
 	}
 
 	for _, cli := range s.opts.Clients {
-		if err = cli.Init(client.Context(s.opts.Context)); err != nil {
+		if err = cli.Init(client.Context(cli.Options().Context)); err != nil {
 			return err
 		}
 	}