refactor(timezone): Refactoring timezone

Signed-off-by: Flc゛ <four_leaf_clover@foxmail.com>

timezone/context.go

@@ -0,0 +1,17 @@
+package timezone
+
+import (
+	"context"
+	"time"
+)
+
+type contextKey struct{}
+
+func NewContext(ctx context.Context, local *time.Location) context.Context {
+	return context.WithValue(ctx, contextKey{}, local)
+}
+
+func FromContext(ctx context.Context) (*time.Location, bool) {
+	local, ok := ctx.Value(contextKey{}).(*time.Location)
+	return local, ok
+}

timezone/provider.go

@@ -17,7 +17,7 @@ func Local(name string) Option {
 	}
 }
 
-func Provider(opts ...Option) func(ctx context.Context) error {
+func Provider(opts ...Option) func(ctx context.Context) (context.Context, error) {
 	op := options{
 		local: "UTC",
 	}
@@ -26,14 +26,14 @@ func Provider(opts ...Option) func(ctx context.Context) error {
 		opt(&op)
 	}
 
-	return func(context.Context) error {
+	return func(ctx context.Context) (context.Context, error) {
 		location, err := time.LoadLocation(op.local)
 		if err != nil {
-			return err
+			return ctx, err
 		}
 
 		time.Local = location
 
-		return nil
+		return NewContext(ctx, location), nil
 	}
 }

timezone/provider_test.go

@@ -11,13 +11,22 @@ import (
 func TestTimezone(t *testing.T) {
 	// before
 	assert.Equal(t, "Local", time.Local.String())
-	assert.NoError(t, Provider()(context.Background()))
+	ctx1, err1 := Provider()(context.Background())
+	assert.NoError(t, err1)
 	assert.Equal(t, "UTC", time.Local.String())
+	local1, ok1 := FromContext(ctx1)
+	assert.True(t, ok1)
+	assert.Equal(t, "UTC", local1.String())
 
 	// after
-	assert.NoError(t, Provider(Local("Asia/Shanghai"))(context.Background()))
+	ctx2, err2 := Provider(Local("Asia/Shanghai"))(context.Background())
+	assert.NoError(t, err2)
 	assert.Equal(t, "Asia/Shanghai", time.Local.String())
+	local2, ok2 := FromContext(ctx2)
+	assert.True(t, ok2)
+	assert.Equal(t, "Asia/Shanghai", local2.String())
 
 	// err
-	assert.Error(t, Provider(Local("Asia/Beijing"))(context.Background()))
+	_, err3 := Provider(Local("Asia/Beijing"))(context.Background())
+	assert.Error(t, err3)
 }