import from main repo

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

handler/meter/meter.go

@@ -0,0 +1,67 @@
+package meter // import "go.unistack.org/micro-server-http/v3/handler/meter"
+
+import (
+	"bytes"
+	"context"
+
+	codecpb "go.unistack.org/micro-proto/v3/codec"
+	"go.unistack.org/micro/v3/errors"
+	"go.unistack.org/micro/v3/meter"
+)
+
+// guard to fail early
+var _ MeterServiceServer = &Handler{}
+
+type Handler struct {
+	opts Options
+}
+
+type Option func(*Options)
+
+type Options struct {
+	Meter        meter.Meter
+	Name         string
+	MeterOptions []meter.Option
+}
+
+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 *codecpb.Frame, rsp *codecpb.Frame) error {
+	buf := bytes.NewBuffer(nil)
+	if err := h.opts.Meter.Write(buf, h.opts.MeterOptions...); err != nil {
+		return errors.InternalServerError(h.opts.Name, "%v", err)
+	}
+
+	rsp.Data = buf.Bytes()
+
+	return nil
+}