เว็บบล็อกเวอร์ชัน-2-1-code-refactoring-5e6b952d6f62018fc5b8ff23

graphql_after_refactor.go

/* schema.go */

// BuildSchema accepts build schema function(s) for applying to the schemabuilding.Schema object
func BuildSchema(buildSchemaFunc ...func(*schemabuilder.Schema)) (*graphql.Schema, error) {
	s := schemabuilder.NewSchema()
	for _, f := range buildSchemaFunc {
		f(s)
	}
	return s.Build()
}

// BuildPostSchema builds all post related schemas
func BuildPostSchema(repository blog.PostRepository) func(*schemabuilder.Schema) {
	return func(s *schemabuilder.Schema) {
		...
		m := s.Mutation()
		m.FieldFunc("updatePostTitle", UpdatePostTitleFieldFunc(repository))
		...
	}
}

// UpdatePostTitleFieldFunc handles the following mutation
// ```graphql
//	mutation {
//		updatePostTitle(slug: string!, title: string!) { ... }
//	}
// ```
func UpdatePostTitleFieldFunc(repository blog.PostRepository) interface{} {
	return func(ctx context.Context, args struct {
		Slug  Slug
		Title string
	}) (blog.Post, error) {
		id := args.Slug.MustGetID()

		p, err := repository.FindByID(ctx, id)
		if err != nil {
			return blog.Post{}, errors.New(http.StatusText(http.StatusNotFound))
		}

		if authID := ctx.Value(AuthorizedID); authID != nil {
			if p.AuthorID == authID.(string) {
				slug := fmt.Sprintf("%s-%s", slugify.Make(args.Title), id.(primitive.ObjectID).Hex())
				return repository.Save(ctx, id, blog.NewPostQueryBuilder().WithTitle(args.Title).WithSlug(slug).
					Build())
			}
		}

		return blog.Post{}, errors.New(http.StatusText(http.StatusForbidden))
	}
}

graphql_before_refactor.go

/* server.go */

// NewServer returns new GraphQL server
func NewServer(blogService blog.Service, fbClient facebook.Client, file storage.FileRepository) *Server {
	return &Server{
		service: service{
			Service:  blogService,
			fbClient: fbClient,
			file:     file,
		},
		schema: schemabuilder.NewSchema(),
	}
}

/* mutation.go */

// RegisterMutation registers pre-defined mutation fields to the provided schema
func (s *Server) RegisterMutation(schema *schemabuilder.Schema) {
	obj := schema.Mutation()

	obj.FieldFunc("updatePostTitle", s.updatePostTitleMutation)
	...
}

// mutation {
//	updatePostTitle(slug: string!, title: string!) {
//		...
//	}
// }
func (s *Server) updatePostTitleMutation(ctx context.Context, args struct {
	Slug  Slug
	Title string
}) (blog.Post, error) {
	id := args.Slug.MustGetID()

	err := s.validateAuthority(ctx, id)
	if err != nil {
		return blog.Post{}, err
	}

	slug := fmt.Sprintf("%s-%s", slugify.Make(args.Title), id.(primitive.ObjectID).Hex())
	return s.service.Post().Save(ctx, id, blog.NewPostQueryBuilder().WithTitle(args.Title).WithSlug(slug).Build())
}

storage_after_refactor.go

/* storage.go */

// Storage uses to storing or retrieving file from cloud or remote server
type Storage interface {
	Delete(ctx context.Context, path string) error
	Download(ctx context.Context, path string) (io.ReadCloser, error)
	Upload(ctx context.Context, body io.Reader, path string) error
}

/* blob.go */

// Bucket embeds the original blob.Bucket for providing compatible storage.Storage interface methods
type Bucket struct{ *blob.Bucket }

// Download provides compatible Download method of the storage.Storage interface
func (b *Bucket) Download(ctx context.Context, path string) (io.ReadCloser, error) {
	return b.Bucket.NewReader(ctx, path, nil)
}

// Upload provides compatible Upload method of the storage.Storage interface
func (b *Bucket) Upload(ctx context.Context, body io.Reader, path string) error {
	w, err := b.Bucket.NewWriter(ctx, path, nil)
	if err != nil {
		return err
	}

	_, err = io.Copy(w, body)
	return err
}