#47

backend/app/controllers/wiki_assets_controller.rb

@@ -0,0 +1,38 @@
+require 'digest'
+
+
+class WikiAssetsController < ApplicationController
+  def index
+    page_id = params[:wiki_page_id].to_i
+    page = WikiPage.find_by(id: page_id)
+    return head :not_found unless page
+
+    render json: page.assets
+  end
+
+  def create
+    return head :unauthorized unless current_user
+    return head :forbidden unless current_user.gte_member?
+
+    wiki_page_id = params[:wiki_page_id].to_i
+    page = WikiPage.find_by(id: wiki_page_id)
+    return head :not_found unless page
+
+    file = params[:file]
+    return head :bad_request if file.blank?
+
+    page.with_lock do
+      no = page.next_asset_no
+      alt_text = params[:alt_text].presence
+      sha256 = Digest::SHA256.file(file.tempfile.path).digest
+
+      asset = WikiAsset.new(wiki_page_id:, no:, alt_text:, sha256:, created_by_user: current_user)
+      asset.file.attach(file)
+      asset.save!
+
+      page.update!(next_asset_no: no + 1)
+    end
+
+    render json: asset.as_json(methods: [:url])
+  end
+end

backend/app/controllers/wiki_pages_controller.rb

@@ -96,7 +96,7 @@ class WikiPagesController < ApplicationController
       message = params[:message].presence
       Wiki::Commit.content!(page:, body:, created_user: current_user, message:)
 
-      render json: WikiPageRepr.base(page), status: :created
+      render json: WikiPageRepr.base(page).merge(body:), status: :created
     else
       render json: { errors: page.errors.full_messages },
              status: :unprocessable_entity
@@ -107,7 +107,7 @@ class WikiPagesController < ApplicationController
     return head :unauthorized unless current_user
     return head :forbidden unless current_user.gte_member?
 
-    title = params[:title]&.strip
+    title = params[:title].to_s.strip
     body = params[:body].to_s
 
     return head :unprocessable_entity if title.blank? || body.blank?
@@ -126,7 +126,7 @@ class WikiPagesController < ApplicationController
                           message:,
                           base_revision_id:)
 
-    head :ok
+    render json: WikiPageRepr.base(page).merge(body:)
   end
 
   def search

backend/app/models/wiki_asset.rb

@@ -0,0 +1,14 @@
+class WikiAsset < ApplicationRecord
+  self.primary_key = :wiki_page_id, :no
+
+  belongs_to :wiki_page
+  belongs_to :created_by_user, class_name: 'User'
+
+  has_one_attached :file
+
+  validates :file, presence: true
+
+  def url
+    Rails.application.routes.url_helpers.rails_blob_url(file, only_path: true)
+  end
+end

backend/app/models/wiki_page.rb

@@ -15,6 +15,8 @@ class WikiPage < ApplicationRecord
            foreign_key: :redirect_page_id,
            dependent: :nullify
 
+  has_many :assets, class_name: 'WikiAsset', dependent: :destroy
+
   belongs_to :tag_name
   validates :tag_name, presence: true
 

backend/config/routes.rb

@@ -41,6 +41,8 @@ Rails.application.routes.draw do
       get :exists
       get :diff
     end
+
+    resources :assets, controller: :wiki_assets, only: [:index, :create]
   end
 
   resources :posts, only: [:index, :show, :create, :update] do

backend/db/migrate/20260323192300_create_wiki_assets.rb

@@ -0,0 +1,16 @@
+class CreateWikiAssets < ActiveRecord::Migration[8.0]
+  def change
+    create_table :wiki_assets, primary_key: [:wiki_page_id, :no] do |t|
+      t.references :wiki_page, null: false, foreign_key: true, index: false
+      t.integer :no, null: false
+      t.string :alt_text
+      t.column :sha256, 'binary(32)', null: false
+      t.references :created_by_user, null: false, foreign_key: { to_table: :users }
+      t.timestamps
+    end
+
+    add_index :wiki_assets, [:wiki_page_id, :sha256], unique: true
+
+    add_column :wiki_pages, :next_asset_no, :integer, null: false, default: 1
+  end
+end

backend/db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[8.0].define(version: 2026_03_17_015000) do
+ActiveRecord::Schema[8.0].define(version: 2026_03_23_192300) do
   create_table "active_storage_attachments", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.string "name", null: false
     t.string "record_type", null: false
@@ -239,6 +239,18 @@ ActiveRecord::Schema[8.0].define(version: 2026_03_17_015000) do
     t.datetime "updated_at", null: false
   end
 
+  create_table "wiki_assets", primary_key: ["wiki_page_id", "no"], charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
+    t.bigint "wiki_page_id", null: false
+    t.integer "no", null: false
+    t.string "alt_text"
+    t.binary "sha256", limit: 32, null: false
+    t.bigint "created_by_user_id", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["created_by_user_id"], name: "index_wiki_assets_on_created_by_user_id"
+    t.index ["wiki_page_id", "sha256"], name: "index_wiki_assets_on_wiki_page_id_and_sha256", unique: true
+  end
+
   create_table "wiki_lines", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.string "sha256", limit: 64, null: false
     t.text "body", null: false
@@ -254,6 +266,7 @@ ActiveRecord::Schema[8.0].define(version: 2026_03_17_015000) do
     t.datetime "created_at", null: false
     t.datetime "updated_at", null: false
     t.datetime "discarded_at"
+    t.integer "next_asset_no", default: 1, null: false
     t.index ["created_user_id"], name: "index_wiki_pages_on_created_user_id"
     t.index ["discarded_at"], name: "index_wiki_pages_on_discarded_at"
     t.index ["tag_name_id"], name: "index_wiki_pages_on_tag_name_id", unique: true
@@ -320,6 +333,8 @@ ActiveRecord::Schema[8.0].define(version: 2026_03_17_015000) do
   add_foreign_key "user_ips", "users"
   add_foreign_key "user_post_views", "posts"
   add_foreign_key "user_post_views", "users"
+  add_foreign_key "wiki_assets", "users", column: "created_by_user_id"
+  add_foreign_key "wiki_assets", "wiki_pages"
   add_foreign_key "wiki_pages", "tag_names"
   add_foreign_key "wiki_pages", "users", column: "created_user_id"
   add_foreign_key "wiki_pages", "users", column: "updated_user_id"

frontend/src/components/WikiBody.tsx

@@ -1,48 +1,10 @@
-import { useQuery } from '@tanstack/react-query'
-import { useMemo } from 'react'
-import ReactMarkdown from 'react-markdown'
-import remarkGFM from 'remark-gfm'
-
-import PrefetchLink from '@/components/PrefetchLink'
-import SectionTitle from '@/components/common/SectionTitle'
-import SubsectionTitle from '@/components/common/SubsectionTitle'
-import { wikiKeys } from '@/lib/queryKeys'
-import remarkWikiAutoLink from '@/lib/remark-wiki-autolink'
-import { fetchWikiPages } from '@/lib/wiki'
+import WikiMarkdown from '@/components/WikiMarkdown'
 
 import type { FC } from 'react'
-import type { Components } from 'react-markdown'
 
 type Props = { title: string
 	       body?: string }
 
-const mdComponents = { h1:  ({ children }) => <SectionTitle>{children}</SectionTitle>,
-		       h2:  ({ children }) => <SubsectionTitle>{children}</SubsectionTitle>,
-		       ol:  ({ children }) => <ol className="list-decimal pl-6">{children}</ol>,
-		       ul:  ({ children }) => <ul className="list-disc pl-6">{children}</ul>,
-		       a:   (({ href, children }) => (
-				['/', '.'].some (e => href?.startsWith (e))
-			        ? <PrefetchLink to={href!}>{children}</PrefetchLink>
-			        : (
-				    <a href={href}
-				       target="_blank"
-				       rel="noopener noreferrer">
-				      {children}
-				    </a>))) } as const satisfies Components
 
-
-export default (({ title, body }: Props) => {
-  const { data } = useQuery ({
-      enabled: Boolean (body),
-      queryKey: wikiKeys.index ({ }),
-      queryFn: () => fetchWikiPages ({ }) })
-  const pageNames = (data ?? []).map (page => page.title).sort ((a, b) => b.length - a.length)
-
-  const remarkPlugins = useMemo (
-      () => [() => remarkWikiAutoLink (pageNames), remarkGFM], [pageNames])
-
-  return (
-      <ReactMarkdown components={mdComponents} remarkPlugins={remarkPlugins}>
-	{body || `このページは存在しません。[新規作成してください](/wiki/new?title=${ encodeURIComponent (title) })。`}
-      </ReactMarkdown>)
-}) satisfies FC<Props>
+export default (({ title, body }: Props) =>
+    <WikiMarkdown title={title} body={body ?? ''}/>) satisfies FC<Props>

frontend/src/components/WikiEditForm.tsx

@@ -0,0 +1,76 @@
+import { useEffect, useState } from 'react'
+import MdEditor from 'react-markdown-editor-lite'
+
+import WikiMarkdown from '@/components/WikiMarkdown'
+import Label from '@/components/common/Label'
+import { apiPost } from '@/lib/api'
+
+import type { FC } from 'react'
+
+import type { WikiAsset } from '@/types'
+
+type Props = {
+    title:    string
+    body:     string
+    onSubmit: (title: string, body: string) => void
+    id?:      number | null }
+
+
+export default (({ title: initTitle, body: initBody, onSubmit, id }: Props) => {
+  const forEdit = id != null
+
+  const [title, setTitle] = useState<string> (initTitle)
+  const [body, setBody] = useState<string> (initBody)
+
+  useEffect (() => {
+    setTitle (initTitle)
+    setBody (initBody)
+  }, [initTitle, initBody])
+
+  const handleImageUpload = async (file: File) => {
+    if (!(forEdit))
+      throw new Error ('画像は Wiki 作成前に追加することができません．')
+
+    const formData = new FormData
+    formData.append ('file', file)
+
+    const asset = await apiPost<WikiAsset> (
+	`/wiki/${ id }/assets`,
+	formData,
+	{ headers: { 'Content-Type': 'multipart/form-data' } })
+
+    return `{{img:${ asset.no }}}`
+  }
+
+  return (
+      <>
+	{/* タイトル */}
+	{/* TODO: タグ補完 */}
+	<div>
+	  <Label>タイトル</Label>
+	  <input
+	      type="text"
+	      value={title}
+	      onChange={e => setTitle (e.target.value)}
+	      className="w-full border p-2 rounded"/>
+	</div>
+
+	{/* 本文 */}
+	<div>
+	  <Label>本文</Label>
+	  <MdEditor
+	      value={body}
+	      style={{ height: '500px' }}
+	      renderHTML={text => <WikiMarkdown body={text} preview/>}
+	      onChange={({ text }) => setBody (text)}
+	      onImageUpload={handleImageUpload}/>
+	</div>
+
+	{/* 送信 */}
+	<button
+	    onClick={() => onSubmit (title, body)}
+	    className="px-4 py-2 bg-blue-600 text-white rounded disabled:bg-gray-400">
+	  {forEdit ? '編輯' : '追加'}
+	</button>
+      </>)
+}) satisfies FC<Props>

frontend/src/components/WikiMarkdown.tsx

@@ -0,0 +1,77 @@
+import { useQuery } from '@tanstack/react-query'
+import { useMemo } from 'react'
+import ReactMarkdown from 'react-markdown'
+import remarkGFM from 'remark-gfm'
+
+import PrefetchLink from '@/components/PrefetchLink'
+import SectionTitle from '@/components/common/SectionTitle'
+import SubsectionTitle from '@/components/common/SubsectionTitle'
+import { wikiKeys } from '@/lib/queryKeys'
+import remarkWikiAutoLink from '@/lib/remark-wiki-autolink'
+import { fetchWikiPages } from '@/lib/wiki'
+
+import type { FC } from 'react'
+import type { Components } from 'react-markdown'
+
+type Props = {
+    title?:   string
+    body:     string
+    preview?: boolean }
+
+
+const makeComponents = (preview = false) => (
+    { h1: ({ children }) => <SectionTitle>{children}</SectionTitle>,
+      h2: ({ children }) => <SubsectionTitle>{children}</SubsectionTitle>,
+      ol: ({ children }) => <ol className="list-decimal pl-6">{children}</ol>,
+      ul: ({ children }) => <ul className="list-disc pl-6">{children}</ul>,
+      a:  ({ href, children }) => {
+	if (!(href))
+	  return <>{children}</>
+
+	if (!(preview) && ['/', '.'].some (e => href.startsWith (e)))
+	  return <PrefetchLink to={href}>{children}</PrefetchLink>
+
+	const ext = /^(?:https?:)?\/\//.test (href)
+
+	return (
+	    <a href={href}
+	       target={ext ? '_blank' : undefined}
+	       rel={ext ? 'noopener noreferrer' : undefined}>
+	      {children}
+	    </a>)
+      },
+      img: (({ src, alt }) => (
+	  <img src={src ?? ''}
+	       alt={alt ?? ''}
+	       className="max-w-full h-auto rounded"/>)),
+    } as const satisfies Components)
+
+
+export default (({ title, body, preview = false }: Props) => {
+  const { data } = useQuery ({
+      queryKey: wikiKeys.index ({ }),
+      queryFn: () => fetchWikiPages ({ }) })
+
+  const pageNames = useMemo (
+      () => (data ?? []).map ((page) => page.title).sort ((a, b) => b.length - a.length),
+      [data])
+
+  const remarkPlugins = useMemo (
+      () => [() => remarkWikiAutoLink (pageNames), remarkGFM],
+      [pageNames])
+
+  const components = useMemo (
+      () => makeComponents (preview),
+      [preview])
+
+  return (
+      <ReactMarkdown
+	  components={components}
+	  remarkPlugins={remarkPlugins}>
+        {body
+	 || (title
+	     ? ('このページは存在しません。'
+		+`[新規作成してください](/wiki/new?title=${ encodeURIComponent (title) })。`)
+	     : '')}
+      </ReactMarkdown>)
+}) satisfies FC<Props>

frontend/src/pages/wiki/WikiEditPage.tsx

@@ -1,10 +1,9 @@
 import { useQueryClient } from '@tanstack/react-query'
-import MarkdownIt from 'markdown-it'
 import { useEffect, useState } from 'react'
 import { Helmet } from 'react-helmet-async'
-import MdEditor from 'react-markdown-editor-lite'
 import { useParams, useNavigate } from 'react-router-dom'
 
+import WikiEditForm from '@/components/WikiEditForm'
 import MainArea from '@/components/layout/MainArea'
 import { toast } from '@/components/ui/use-toast'
 import { SITE_TITLE } from '@/config'
@@ -18,8 +17,6 @@ import type { FC } from 'react'
 
 import type { User, WikiPage } from '@/types'
 
-const mdParser = new MarkdownIt
-
 type Props = { user: User | null }
 
 
@@ -37,7 +34,7 @@ export default (({ user }: Props) => {
   const [loading, setLoading] = useState (true)
   const [title, setTitle] = useState ('')
 
-  const handleSubmit = async () => {
+  const handleSubmit = async (title: string, body: string) => {
     const formData = new FormData ()
     formData.append ('title', title)
     formData.append ('body', body)
@@ -46,8 +43,6 @@ export default (({ user }: Props) => {
     {
       await apiPut (`/wiki/${ id }`, formData,
 		    { headers: { 'Content-Type': 'multipart/form-data' } })
-      qc.setQueryData (wikiKeys.show (title, { }),
-		       (prev: WikiPage) => ({ ...prev, title, body }))
       qc.invalidateQueries ({ queryKey: wikiKeys.root })
       toast ({ title: '投稿成功!' })
       navigate (`/wiki/${ title }`)
@@ -77,32 +72,11 @@ export default (({ user }: Props) => {
 	  <h1 className="text-2xl font-bold mb-2">Wiki ページを編輯</h1>
 
 	  {loading ? 'Loading...' : (
-	      <>
-		{/* タイトル */}
-		{/* TODO: タグ補完 */}
-		<div>
-		  <label className="block font-semibold mb-1">タイトル</label>
-		  <input type="text"
-			 value={title}
-			 onChange={e => setTitle (e.target.value)}
-			 className="w-full border p-2 rounded"/>
-		</div>
-
-		{/* 本文 */}
-		<div>
-		  <label className="block font-semibold mb-1">本文</label>
-		  <MdEditor value={body}
-			    style={{ height: '500px' }}
-			    renderHTML={text => mdParser.render (text)}
-			    onChange={({ text }) => setBody (text)}/>
-		</div>
-
-		{/* 送信 */}
-		<button onClick={handleSubmit}
-			className="px-4 py-2 bg-blue-600 text-white rounded disabled:bg-gray-400">
-		  編輯
-		</button>
-	      </>)}
+	      <WikiEditForm
+		  title={title}
+		  body={body}
+		  onSubmit={handleSubmit}
+		  id={Number (id)}/>)}
 	</div>
       </MainArea>)
 }) satisfies FC<Props>

frontend/src/pages/wiki/WikiNewPage.tsx

@@ -1,21 +1,19 @@
-import MarkdownIt from 'markdown-it'
-import { useState } from 'react'
+import { useQueryClient } from '@tanstack/react-query'
 import { Helmet } from 'react-helmet-async'
-import MdEditor from 'react-markdown-editor-lite'
 import { useLocation, useNavigate } from 'react-router-dom'
 
+import WikiEditForm from '@/components/WikiEditForm'
 import MainArea from '@/components/layout/MainArea'
 import { toast } from '@/components/ui/use-toast'
 import { SITE_TITLE } from '@/config'
 import { apiPost } from '@/lib/api'
+import { wikiKeys } from '@/lib/queryKeys'
 import Forbidden from '@/pages/Forbidden'
 
 import 'react-markdown-editor-lite/lib/index.css'
 
 import type { User, WikiPage } from '@/types'
 
-const mdParser = new MarkdownIt
-
 type Props = { user: User | null }
 
 
@@ -26,13 +24,12 @@ export default ({ user }: Props) => {
   const location = useLocation ()
   const navigate = useNavigate ()
 
+  const qc = useQueryClient ()
+
   const query = new URLSearchParams (location.search)
   const titleQuery = query.get ('title') ?? ''
 
-  const [title, setTitle] = useState (titleQuery)
-  const [body, setBody] = useState ('')
-
-  const handleSubmit = async () => {
+  const handleSubmit = async (title: string, body: string) => {
     const formData = new FormData
     formData.append ('title', title)
     formData.append ('body', body)
@@ -40,7 +37,8 @@ export default ({ user }: Props) => {
     try
     {
       const data = await apiPost<WikiPage> ('/wiki', formData,
-				  { headers: { 'Content-Type': 'multipart/form-data' } })
+	  { headers: { 'Content-Type': 'multipart/form-data' } })
+      qc.invalidateQueries ({ queryKey: wikiKeys.root })
       toast ({ title: '投稿成功!' })
       navigate (`/wiki/${ data.title }`)
     }
@@ -58,30 +56,10 @@ export default ({ user }: Props) => {
 	<div className="max-w-xl mx-auto p-4 space-y-4">
 	  <h1 className="text-2xl font-bold mb-2">新規 Wiki ページ</h1>
 
-	  {/* タイトル */}
-	  {/* TODO: タグ補完 */}
-	  <div>
-	    <label className="block font-semibold mb-1">タイトル</label>
-	    <input type="text"
-		   value={title}
-		   onChange={e => setTitle (e.target.value)}
-		   className="w-full border p-2 rounded"/>
-	  </div>
-
-	  {/* 本文 */}
-	  <div>
-	    <label className="block font-semibold mb-1">本文</label>
-	    <MdEditor value={body}
-		      style={{ height: '500px' }}
-		      renderHTML={text => mdParser.render (text)}
-		      onChange={({ text }) => setBody (text)}/>
-	  </div>
-
-	  {/* 送信 */}
-	  <button onClick={handleSubmit}
-		  className="px-4 py-2 bg-blue-600 text-white rounded disabled:bg-gray-400">
-	    追加
-	  </button>
+	  <WikiEditForm
+	      title={titleQuery}
+	      body=""
+	      onSubmit={handleSubmit}/>
 	</div>
       </MainArea>)
 }

frontend/src/types.ts

@@ -149,6 +149,11 @@ export type User = {
 
 export type ViewFlagBehavior = typeof ViewFlagBehavior[keyof typeof ViewFlagBehavior]
 
+export type WikiAsset = {
+    wikiPageId: number
+    no:         number
+    url:        string }
+
 export type WikiPage = {
     id:             number
     title:          string