many fixes for lint and context.Context usage (#5)

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

api/router/options.go

@@ -1,6 +1,8 @@
 package router
 
 import (
+	"context"
+
 	"github.com/unistack-org/micro/v3/api/resolver"
 	"github.com/unistack-org/micro/v3/api/resolver/vpath"
 	"github.com/unistack-org/micro/v3/registry"
@@ -10,12 +12,14 @@ type Options struct {
 	Handler  string
 	Registry registry.Registry
 	Resolver resolver.Resolver
+	Context  context.Context
 }
 
 type Option func(o *Options)
 
 func NewOptions(opts ...Option) Options {
 	options := Options{
+		Context: context.Background(),
 		Handler: "meta",
 	}
 
@@ -32,18 +36,28 @@ func NewOptions(opts ...Option) Options {
 	return options
 }
 
+// WithContext sets the context
+func WithContext(ctx context.Context) Option {
+	return func(o *Options) {
+		o.Context = ctx
+	}
+}
+
+// WithHandler sets the handler
 func WithHandler(h string) Option {
 	return func(o *Options) {
 		o.Handler = h
 	}
 }
 
+// WithRegistry sets the registry
 func WithRegistry(r registry.Registry) Option {
 	return func(o *Options) {
 		o.Registry = r
 	}
 }
 
+// WithResolver sets the resolver
 func WithResolver(r resolver.Resolver) Option {
 	return func(o *Options) {
 		o.Resolver = r