HyeKyoZ-github (朱德培)

请问一下 ruby 现在可以显示调用私有方法了（self.private_method）？

HyeKyoZ-github — Sun, 25 Feb 2024 17:41:04 +0800


class C
  def public_method
    self.private_method
  end

  private
  def private_method; end

end

C.new.public_method

上面代码在 ruby 3.3.0 里面成功执行，没报错。执行结果如图

validates unless 问题

HyeKyoZ-github — Mon, 19 Jul 2021 21:33:17 +0800

见图，请问下这里为什么使用 unless: -> { system_event? }，而不是直接 unless: :system_event?

Rails API 多次 Rendered

HyeKyoZ-github — Thu, 15 Jul 2021 17:05:42 +0800

使用 ActiveStorage 组件，为了避免 N+1 查询，使用了 has_one_attached: :field 对应的 with_attached_field 方法，之后就出现了多次 Rendered。这里去掉 .with_attached_attachment .with_attached_icon 这两个方法之后就正常了。

Started GET "/api/v1/posts?writable_id=2&writable_type=Navigation&query=%E6%96%87%E7%AB%A0" for ::1 at 2021-07-15 16:51:34 +0800
   (69.6ms)  SELECT `schema_migrations`.`version` FROM `schema_migrations` ORDER BY `schema_migrations`.`version` ASC
Processing by PostsController#index as */*
  Parameters: {"writable_id"=>"2", "writable_type"=>"Navigation", "query"=>"文章"}
  Navigation Load (69.0ms)  SELECT `navigations`.* FROM `navigations` WHERE `navigations`.`id` = 2 LIMIT 1
  ↳ app/controllers/posts_controller.rb:10:in `index'
  Rendering posts/index.json.jbuilder
   (68.9ms)  SELECT COUNT(*) FROM `posts` INNER JOIN `writings` ON `posts`.`id` = `writings`.`post_id` WHERE `writings`.`writable_id` = 2 AND `writings`.`writable_type` = 'Navigation' AND (title like '%文章%' or content like '%文章%')
  ↳ app/views/posts/index.json.jbuilder:1
  Post Load (137.4ms)  SELECT `posts`.* FROM `posts` INNER JOIN `writings` ON `posts`.`id` = `writings`.`post_id` WHERE `writings`.`writable_id` = 2 AND `writings`.`writable_type` = 'Navigation' AND (title like '%文章%' or content like '%文章%') ORDER BY `posts`.`id` DESC LIMIT 25 OFFSET 0
  ↳ app/views/posts/index.json.jbuilder:2
  Writing Load (68.0ms)  SELECT `writings`.* FROM `writings` WHERE `writings`.`writable_type` = 'Navigation' AND `writings`.`post_id` IN (47, 46, 45, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22)
  ↳ app/views/posts/index.json.jbuilder:2
  Navigation Load (78.1ms)  SELECT `navigations`.* FROM `navigations` WHERE `navigations`.`id` IN (1, 2)
  ↳ app/views/posts/index.json.jbuilder:2
  Writing Load (75.3ms)  SELECT `writings`.* FROM `writings` WHERE `writings`.`writable_type` = 'Theme' AND `writings`.`post_id` IN (47, 46, 45, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22)
  ↳ app/views/posts/index.json.jbuilder:2
  Theme Load (65.9ms)  SELECT `themes`.* FROM `themes` WHERE `themes`.`id` = 12
  ↳ app/views/posts/index.json.jbuilder:2
  ActiveStorage::Attachment Load (73.8ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' AND `active_storage_attachments`.`record_id` IN (47, 46, 45, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22)
  ↳ app/views/posts/index.json.jbuilder:2
  ActiveStorage::Attachment Load (84.3ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' AND `active_storage_attachments`.`record_id` IN (47, 46, 45, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22)
  ↳ app/views/posts/index.json.jbuilder:2
  Rendered posts/_post.json.jbuilder (Duration: 1.4ms | Allocations: 322)
  Rendered posts/_post.json.jbuilder (Duration: 0.2ms | Allocations: 73)
  Rendered posts/_post.json.jbuilder (Duration: 0.2ms | Allocations: 73)
  Rendered posts/_post.json.jbuilder (Duration: 0.2ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.2ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.2ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.2ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.3ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.2ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.2ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.1ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.1ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.1ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.1ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.2ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.1ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.1ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.1ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.1ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.1ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.1ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.1ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.1ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.1ms | Allocations: 74)
  Rendered posts/_post.json.jbuilder (Duration: 0.1ms | Allocations: 74)
  Rendered posts/index.json.jbuilder (Duration: 1056.0ms | Allocations: 38657)
Completed 200 OK in 1524ms (Views: 131.5ms | ActiveRecord: 1338.4ms | Allocations: 59390)

下面是相关代码

# PostsController#index
def index
  scope = Post.all
  if params[:writable_id].present? and params[:writable_type].present?
    writable = case params[:writable_type]
               when Navigation.name
                 Navigation.find(params[:writable_id])
               when Theme.name
                 Theme.find(params[:writable_id])
               else
                 raise ArgumentError, "writable_type: #{params[:writable_type]} is invalid."
               end
    scope = writable.posts
  end
  scope = scope.where(kind: params[:kind]) if params[:kind].present?
  scope = scope.where("title like ?", "%#{params[:query]}%") if params[:query].present?
  @posts = scope.with_attached_attachment
                .with_attached_icon
                .preload(:navigations, :themes)
                .page(params[:page]).per(params[:limit])
                .order(id: :desc)
end

class Post < ApplicationRecord
  enum kind: { notice: 0, article: 1 }
  enum source: { original: 0, link: 1 }
  enum jump_type: { jump_link: 0, mini_program: 1 }

  has_one_attached :icon
  has_one_attached :attachment

  has_many :writings
  has_many :navigations, through: :writings, source: :writable, source_type: 'Navigation'
  has_many :themes, through: :writings, source: :writable, source_type: 'Theme'
end

下面是去掉 .with_attached_attachment .with_attached_icon 这两个方法之后 log

Started GET "/api/v1/posts?writable_id=2&writable_type=Navigation&query=%E6%96%87%E7%AB%A0" for ::1 at 2021-07-15 17:20:31 +0800
   (64.5ms)  SELECT `schema_migrations`.`version` FROM `schema_migrations` ORDER BY `schema_migrations`.`version` ASC
Processing by PostsController#index as */*
  Parameters: {"writable_id"=>"2", "writable_type"=>"Navigation", "query"=>"文章"}
  Navigation Load (72.1ms)  SELECT `navigations`.* FROM `navigations` WHERE `navigations`.`id` = 2 LIMIT 1
  ↳ app/controllers/posts_controller.rb:10:in `index'
  Rendering posts/index.json.jbuilder
   (60.8ms)  SELECT COUNT(*) FROM `posts` INNER JOIN `writings` ON `posts`.`id` = `writings`.`post_id` WHERE `writings`.`writable_id` = 2 AND `writings`.`writable_type` = 'Navigation' AND (title like '%文章%')
  ↳ app/views/posts/index.json.jbuilder:1
  Post Load (229.0ms)  SELECT `posts`.* FROM `posts` INNER JOIN `writings` ON `posts`.`id` = `writings`.`post_id` WHERE `writings`.`writable_id` = 2 AND `writings`.`writable_type` = 'Navigation' AND (title like '%文章%') ORDER BY `posts`.`id` DESC LIMIT 25 OFFSET 0
  ↳ app/views/posts/index.json.jbuilder:2
  Writing Load (77.0ms)  SELECT `writings`.* FROM `writings` WHERE `writings`.`writable_type` = 'Navigation' AND `writings`.`post_id` IN (47, 46, 45, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22)
  ↳ app/views/posts/index.json.jbuilder:2
  Navigation Load (75.7ms)  SELECT `navigations`.* FROM `navigations` WHERE `navigations`.`id` IN (1, 2)
  ↳ app/views/posts/index.json.jbuilder:2
  Writing Load (72.5ms)  SELECT `writings`.* FROM `writings` WHERE `writings`.`writable_type` = 'Theme' AND `writings`.`post_id` IN (47, 46, 45, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22)
  ↳ app/views/posts/index.json.jbuilder:2
  Theme Load (94.7ms)  SELECT `themes`.* FROM `themes` WHERE `themes`.`id` = 12
  ↳ app/views/posts/index.json.jbuilder:2
  ActiveStorage::Attachment Load (82.1ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 47 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (68.2ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 47 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 265.2ms | Allocations: 4326)
  ActiveStorage::Attachment Load (67.3ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 46 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (76.4ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 46 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 149.8ms | Allocations: 1787)
  ActiveStorage::Attachment Load (71.2ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 45 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (93.4ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 45 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 171.1ms | Allocations: 1771)
  ActiveStorage::Attachment Load (78.6ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 43 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (64.2ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 43 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 146.7ms | Allocations: 1772)
  ActiveStorage::Attachment Load (69.9ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 42 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (64.9ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 42 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 139.1ms | Allocations: 1772)
  ActiveStorage::Attachment Load (70.5ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 41 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (86.1ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 41 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 161.7ms | Allocations: 1778)
  ActiveStorage::Attachment Load (70.0ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 40 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (77.7ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 40 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 153.8ms | Allocations: 1772)
  ActiveStorage::Attachment Load (75.5ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 39 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (85.3ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 39 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 166.5ms | Allocations: 1772)
  ActiveStorage::Attachment Load (84.6ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 38 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (104.6ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 38 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 195.1ms | Allocations: 1772)
  ActiveStorage::Attachment Load (91.9ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 37 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (73.4ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 37 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 170.7ms | Allocations: 1772)
  ActiveStorage::Attachment Load (67.8ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 36 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (78.3ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 36 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 153.8ms | Allocations: 1772)
  ActiveStorage::Attachment Load (68.2ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 35 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (63.4ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 35 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 137.9ms | Allocations: 1773)
  ActiveStorage::Attachment Load (85.7ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 34 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (62.6ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 34 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 152.7ms | Allocations: 1772)
  ActiveStorage::Attachment Load (65.1ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 33 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (70.3ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 33 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 140.4ms | Allocations: 1772)
  ActiveStorage::Attachment Load (68.9ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 32 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (75.7ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 32 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 151.2ms | Allocations: 1772)
  ActiveStorage::Attachment Load (70.3ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 31 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (78.2ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 31 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 153.3ms | Allocations: 1772)
  ActiveStorage::Attachment Load (74.5ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 30 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (74.9ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 30 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 155.8ms | Allocations: 1772)
  ActiveStorage::Attachment Load (81.9ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 29 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (84.5ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 29 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 172.7ms | Allocations: 1776)
  ActiveStorage::Attachment Load (73.3ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 28 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (71.7ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 28 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 150.7ms | Allocations: 1772)
  ActiveStorage::Attachment Load (79.9ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 27 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (75.2ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 27 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 160.4ms | Allocations: 1772)
  ActiveStorage::Attachment Load (80.3ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 26 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (74.2ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 26 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 159.8ms | Allocations: 1772)
  ActiveStorage::Attachment Load (108.3ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 25 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (85.2ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 25 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 199.2ms | Allocations: 1772)
  ActiveStorage::Attachment Load (70.8ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 24 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (63.1ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 24 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 139.1ms | Allocations: 1772)
  ActiveStorage::Attachment Load (78.2ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 23 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (79.5ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 23 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 162.6ms | Allocations: 1772)
  ActiveStorage::Attachment Load (67.3ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 22 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'icon' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:5
  ActiveStorage::Attachment Load (83.7ms)  SELECT `active_storage_attachments`.* FROM `active_storage_attachments` WHERE `active_storage_attachments`.`record_id` = 22 AND `active_storage_attachments`.`record_type` = 'Post' AND `active_storage_attachments`.`name` = 'attachment' LIMIT 1
  ↳ app/views/posts/_post.json.jbuilder:14
  Rendered posts/_post.json.jbuilder (Duration: 156.9ms | Allocations: 1773)
  Rendered posts/index.json.jbuilder (Duration: 4976.1ms | Allocations: 79057)
Completed 200 OK in 5492ms (Views: 224.6ms | ActiveRecord: 5210.9ms | Allocations: 99695)

Rails 连接数据库出错

HyeKyoZ-github — Wed, 12 May 2021 11:10:35 +0800

gemfile

使用 rails new almond -d mysql 命令创建了一个新项目接着就修改了一下 config/database.yaml 里的 password，如图：然后执行 rails db:create 报错，如图请问下这个有人遇到吗？

database.yml

# MySQL. Versions 5.5.8 and up are supported.
#
# Install the MySQL driver
#   gem install mysql2
#
# Ensure the MySQL gem is defined in your Gemfile
#   gem 'mysql2'
#
# And be sure to use new-style password hashing:
#   https://dev.mysql.com/doc/refman/5.7/en/password-hashing.html
#
default: &default
  adapter: mysql2
  encoding: utf8mb4
  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
  username: root
  password: root
  socket: /tmp/mysql.sock

development:
  <<: *default
  database: almond_development

# Warning: The database defined as "test" will be erased and
# re-generated from your development database when you run "rake".
# Do not set this db to the same as development or production.
test:
  <<: *default
  database: almond_test

# As with config/credentials.yml, you never want to store sensitive information,
# like your database password, in your source code. If your source code is
# ever seen by anyone, they now have access to your database.
#
# Instead, provide the password or a full connection URL as an environment
# variable when you boot the app. For example:
#
#   DATABASE_URL="mysql2://myuser:mypass@localhost/somedatabase"
#
# If the connection URL is provided in the special DATABASE_URL environment
# variable, Rails will automatically merge its configuration values on top of
# the values provided in this file. Alternatively, you can specify a connection
# URL environment variable explicitly:
#
#   production:
#     url: <%= ENV['MY_APP_DATABASE_URL'] %>
#
# Read https://guides.rubyonrails.org/configuring.html#configuring-a-database
# for a full overview on how database connection configuration can be specified.
#
production:
  <<: *default
  database: almond_production
  username: almond
  password: <%= ENV['ALMOND_DATABASE_PASSWORD'] %>

请教关于 ActionCable 的问题

HyeKyoZ-github — Wed, 29 Nov 2017 16:16:13 +0800

代码

我是按照rails/actioncable-examples做的

我的问题代码放在这儿

问题

问题描述：

问什么会提交 2 次？

问题截图：

问题已解决。谢谢大家。引发此问题的原因请参考回答里。

请教大家一个关于 Ruby 的 Array 的问题？

HyeKyoZ-github — Tue, 26 Sep 2017 20:09:37 +0800

a = Array.new 3 do
      [0, 0, 0]
    end
a[0][1] = 2

# [[0, 2, 0], [0, 0, 0], [0, 0, 0]]
p a

###################

b = [0, 0, 0]
c = Array.new 3 do
      b
    end 
c[0][1] = 2

# [[0, 2, 0], [0, 2, 0], [0, 2, 0]]
p c

###################

d = Array.new(3, [0, 0, 0])
d[0][1] = 2

# [[0, 2, 0], [0, 2, 0], [0, 2, 0]]
p d

###################

根据以上结果产生的问题：三种初始化的结果为什么不同？a 与 d？，d 与 c？

测试环境：ruby 2.4.2p198 (2017-09-14 revision 59899) [x86_64-darwin17]

谢谢大家！