From e9e861a68896d66132c54d03d8b95702d430b758 Mon Sep 17 00:00:00 2001
From: Vasiliy Tolstov <v.tolstov@unistack.org>
Date: Fri, 4 Dec 2020 00:47:59 +0300
Subject: [PATCH] fixup after/before load/save

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>
---
 config/noop_test.go | 61 +++++++++++++++++++++++++++++++++++++++++++++
 config/options.go   | 30 ++++++++++++++++++++++
 service.go          | 18 +++++++++----
 3 files changed, 104 insertions(+), 5 deletions(-)
 create mode 100644 config/noop_test.go

diff --git a/config/noop_test.go b/config/noop_test.go
new file mode 100644
index 00000000..9b58926d
--- /dev/null
+++ b/config/noop_test.go
@@ -0,0 +1,61 @@
+package config_test
+
+import "testing"
+import "context"
+import "fmt"
+import "github.com/unistack-org/micro/v3/config"
+
+type Cfg struct {
+	Value string
+}
+
+func TestNoop(t *testing.T) {
+	ctx := context.Background()
+	conf := &Cfg{}
+	blfn := func(ctx context.Context, cfg config.Config) error {
+		conf, ok := cfg.Options().Struct.(*Cfg)
+		if !ok {
+			return fmt.Errorf("failed to get Struct from options: %v", cfg.Options())
+		}
+		conf.Value = "before_load"
+		return nil
+	}
+	alfn := func(ctx context.Context, cfg config.Config) error {
+		conf, ok := cfg.Options().Struct.(*Cfg)
+		if !ok {
+			return fmt.Errorf("failed to get Struct from options: %v", cfg.Options())
+		}
+		conf.Value = "after_load"
+		return nil
+	}
+
+
+	cfg := config.NewConfig(config.Struct(conf),config.BeforeLoad(blfn),config.AfterLoad(alfn))
+	if err := cfg.Init(); err != nil {
+		t.Fatal(err)
+	}
+	for _, fn := range cfg.Options().BeforeLoad {
+		if err := fn(ctx, cfg); err != nil {
+			t.Fatal(err)
+		}
+	}
+	if conf.Value != "before_load" {
+		t.Fatal("BeforeLoad option not working")
+	}
+
+	if err := cfg.Load(ctx); err != nil {
+		t.Fatal(err)
+	}
+
+	for _, fn := range cfg.Options().AfterLoad {
+		if err := fn(ctx, cfg); err != nil {
+			t.Fatal(err)
+		}
+	}
+	if conf.Value != "after_load" {
+		t.Fatal("AfterLoad option not working")
+	}
+
+
+
+}
diff --git a/config/options.go b/config/options.go
index 5e50c88c..e6d050cd 100644
--- a/config/options.go
+++ b/config/options.go
@@ -7,6 +7,10 @@ import (
 )
 
 type Options struct {
+	BeforeLoad []func(context.Context, Config) error
+	AfterLoad []func(context.Context, Config) error
+	BeforeSave []func(context.Context, Config) error
+	AfterSave []func(context.Context, Config) error
 	// Struct that holds config data
 	Struct interface{}
 	// struct tag name
@@ -30,6 +34,32 @@ func NewOptions(opts ...Option) Options {
 	return options
 }
 
+func BeforeLoad(fn ...func(context.Context, Config) error) Option {
+	return func(o *Options) {
+		o.BeforeLoad = fn
+	}
+}
+
+func AfterLoad(fn ...func(context.Context, Config) error) Option {
+	return func(o *Options) {
+		o.AfterLoad = fn
+	}
+}
+
+func BeforeSave(fn ...func(context.Context, Config) error) Option {
+	return func(o *Options) {
+		o.BeforeSave = fn
+	}
+}
+
+func AfterSave(fn ...func(context.Context, Config) error) Option {
+	return func(o *Options) {
+		o.AfterSave= fn
+	}
+}
+
+
+
 func Context(ctx context.Context) Option {
 	return func(o *Options) {
 		o.Context = ctx
diff --git a/service.go b/service.go
index 3dba4c97..dac93600 100644
--- a/service.go
+++ b/service.go
@@ -50,9 +50,7 @@ func (s *service) Init(opts ...Option) error {
 
 	if s.opts.Configs != nil {
 		for _, c := range s.opts.Configs {
-			if err := c.Init(
-				config.Context(s.opts.Context),
-			); err != nil {
+			if err := c.Init(config.Context(s.opts.Context)	); err != nil {
 				return err
 			}
 		}
@@ -158,10 +156,20 @@ func (s *service) Start() error {
 		}
 	}
 
-	for idx := 0; idx < len(s.opts.Configs); idx++ {
-		if err := s.opts.Configs[idx].Load(s.opts.Context); err != nil {
+	for _, cfg := range s.opts.Configs {
+		for _, fn := range cfg.Options().BeforeLoad {
+			if err := fn(s.opts.Context, cfg); err != nil {
+				return err
+			}
+		}
+		if err := cfg.Load(s.opts.Context); err != nil {
 			return err
 		}
+		for _, fn := range cfg.Options().AfterLoad {
+			if err := fn(s.opts.Context, cfg); err != nil {
+				return err
+			}
+		}
 	}
 
 	if s.opts.Server == nil {