#399

backend/app/controllers/posts_controller.rb

@@ -175,15 +175,23 @@ class PostsController < ApplicationController
     return head :unauthorized unless current_user
     return head :forbidden unless current_user.gte_member?
 
-    if bool?(:dry)
-      preflight = PostCreatePreflight.new(
-          attributes: post_create_attributes,
-          thumbnail: params[:thumbnail]).run
-      return render json: preflight
-    end
+    preflight = PostCreatePreflight.new(
+        attributes: post_create_attributes,
+        thumbnail: params[:thumbnail]).run
+    return render json: preflight if bool?(:dry)
 
     post = PostCreator.new(actor: current_user,
                            attributes: post_create_attributes.merge(
+                               preflight.slice(
+                                   :url,
+                                   :title,
+                                   :thumbnail_base,
+                                   :tags,
+                                   :parent_post_ids,
+                                   :original_created_from,
+                                   :original_created_before,
+                                   :duration,
+                                   :video_ms).symbolize_keys).merge(
                                thumbnail: params[:thumbnail])).create!
 
     post.reload
@@ -532,6 +540,7 @@ class PostsController < ApplicationController
   def parse_bulk_posts_manifest
     manifest = params[:posts]
     raise ArgumentError, 'posts は必須です．' if manifest.blank?
+    raise ArgumentError, 'posts は JSON 文字列で指定してください．' unless manifest.is_a?(String)
 
     posts = JSON.parse(manifest)
     raise ArgumentError, 'posts は配列で指定してください．' unless posts.is_a?(Array)
@@ -569,15 +578,7 @@ class PostsController < ApplicationController
     return nil if post_id.blank?
 
     post = Post.with_attached_thumbnail.find_by(id: post_id)
-    return nil if post.nil?
-
-    { id: post.id,
-      title: post.title,
-      url: post.url,
-      thumbnail_url:
-          if post.thumbnail.attached?
-            rails_storage_proxy_url(post.thumbnail, only_path: false)
-          end }
+    PostCompactRepr.base(post)
   end
 
   def sync_parent_posts! post, parent_post_ids

backend/app/representations/post_compact_repr.rb

@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+
+module PostCompactRepr
+  module_function
+
+  def base post
+    return nil if post.nil?
+
+    {
+        id: post.id,
+        title: post.title,
+        url: post.url,
+        thumbnail_url: thumbnail_url(post) }
+  end
+
+  def thumbnail_url post
+    return nil unless post.thumbnail.attached?
+
+    Rails.application.routes.url_helpers.rails_storage_proxy_url(
+        post.thumbnail,
+        only_path: false)
+  rescue
+    nil
+  end
+end

backend/app/services/post_bulk_creator.rb

@@ -55,14 +55,21 @@ class PostBulkCreator
         errors: e.record.errors.to_hash,
         base_errors: e.record.errors[:base] }
   rescue ActiveRecord::RecordNotUnique => e
-    raise unless e.message.include?('index_posts_on_url')
-
-    existing_post = existing_post_for_race(attributes)
-    raise if existing_post.nil?
+    if e.message.include?('index_posts_on_url')
+      existing_post = existing_post_for_race(attributes)
+      return {
+          status: 'skipped',
+          existing_post: existing_post } if existing_post.present?
+    end
 
+    Rails.logger.error(
+        "post_bulk_creator_record_not_unique #{ { error: e.class.name,
+                                                 message: e.message }.to_json }")
     {
-        status: 'skipped',
-        existing_post: existing_post }
+        status: 'failed',
+        recoverable: false,
+        errors: { base: ['登録中にエラーが発生しました．'] },
+        base_errors: [] }
   rescue Tag::NicoTagNormalisationError
     {
         status: 'failed',
@@ -134,17 +141,6 @@ class PostBulkCreator
   end
 
   def compact_existing_post post
-    return nil if post.nil?
-
-    {
-        id: post.id,
-        title: post.title,
-        url: post.url,
-        thumbnail_url:
-            if post.thumbnail.attached?
-              Rails.application.routes.url_helpers.rails_storage_proxy_url(
-                  post.thumbnail,
-                  only_path: false)
-            end }
+    PostCompactRepr.base(post)
   end
 end

backend/app/services/post_create_preflight.rb

@@ -88,17 +88,6 @@ class PostCreatePreflight
     return nil if post_id.blank?
 
     post = Post.with_attached_thumbnail.find_by(id: post_id)
-    return nil if post.nil?
-
-    {
-        id: post.id,
-        title: post.title,
-        url: post.url,
-        thumbnail_url:
-            if post.thumbnail.attached?
-              Rails.application.routes.url_helpers.rails_storage_proxy_url(
-                  post.thumbnail,
-                  only_path: false)
-            end }
+    PostCompactRepr.base(post)
   end
 end

backend/app/services/post_import_previewer.rb

@@ -255,7 +255,15 @@ class PostImportPreviewer
   def sanitise_metadata_url value
     return nil unless value.is_a?(String)
 
-    PostUrlNormaliser.normalise(value)
+    stripped = value.strip
+    return nil if stripped.blank?
+
+    uri = URI.parse(stripped)
+    return nil unless uri.is_a?(URI::HTTP) && uri.host.present?
+
+    stripped
+  rescue URI::InvalidURIError
+    nil
   end
 
   def sanitise_metadata_time value

frontend/src/components/posts/PostCreationDataFields.tsx

@@ -17,13 +17,15 @@ type Props = {
     type?:       string
     placeholder?: string }
   thumbnailField: ReactNode
-  core:           PostCoreDataFieldsProps }
+  core:           PostCoreDataFieldsProps
+  extraFields?:   ReactNode }
 
 
 const PostCreationDataFields: FC<Props> = (
     { url,
       thumbnailField,
-      core },
+      core,
+      extraFields },
 ) => (
     <>
       <PostTextField
@@ -39,6 +41,8 @@ const PostCreationDataFields: FC<Props> = (
       {thumbnailField}
 
       <PostCoreDataFields {...core}/>
+
+      {extraFields}
     </>)
 
 export default PostCreationDataFields

frontend/src/components/posts/PostDurationField.tsx

@@ -21,8 +21,7 @@ const PostDurationField: FC<Props> = (
         onChange={onChange}
         errors={errors}
         disabled={disabled}
-        type="text"
-        placeholder="例: 2 / 2.5 / 1:23"/>
+        type="text"/>
 )
 
 export default PostDurationField

frontend/src/components/posts/PostThumbnailPreview.tsx

@@ -6,6 +6,7 @@ import type { FC } from 'react'
 
 type Props = {
   url:        string
+  file?:      File
   alt?:       string
   className?: string
   referrerPolicy?: 'no-referrer' }
@@ -13,17 +14,36 @@ type Props = {
 
 const PostThumbnailPreview: FC<Props> = (
     { url,
+      file,
       alt = 'サムネール',
       className = 'h-16 w-16',
       referrerPolicy },
 ) => {
   const [failed, setFailed] = useState (false)
+  const [fileUrl, setFileUrl] = useState<string | null> (null)
 
   useEffect (() => {
     setFailed (false)
-  }, [url])
+  }, [file, url])
 
-  if (!(url) || failed)
+  useEffect (() => {
+    if (file == null)
+      {
+        setFileUrl (null)
+        return
+      }
+
+    const nextUrl = URL.createObjectURL (file)
+    setFileUrl (nextUrl)
+
+    return () => {
+      URL.revokeObjectURL (nextUrl)
+    }
+  }, [file])
+
+  const resolvedUrl = url.trim () !== '' ? url : (fileUrl ?? '')
+
+  if (resolvedUrl === '' || failed)
     {
       return (
           <div
@@ -34,7 +54,7 @@ const PostThumbnailPreview: FC<Props> = (
 
   return (
       <img
-          src={url}
+          src={resolvedUrl}
           alt={alt}
           referrerPolicy={referrerPolicy}
           className={cn (className, 'rounded border border-border object-cover')}

frontend/src/components/posts/import/PostImportRowForm.tsx

@@ -3,8 +3,10 @@ import { useCallback, useEffect, useMemo, useState } from 'react'
 import FieldError from '@/components/common/FieldError'
 import FieldWarning from '@/components/common/FieldWarning'
 import PostCreationDataFields from '@/components/posts/PostCreationDataFields'
+import PostDurationField from '@/components/posts/PostDurationField'
 import PostTextField from '@/components/posts/PostTextField'
 import PostImportThumbnailPreview from '@/components/posts/import/PostImportThumbnailPreview'
+import { hasThumbnailBaseValue, hasVideoTag } from '@/lib/postImportRows'
 
 import type { FC } from 'react'
 
@@ -21,6 +23,8 @@ type Props = {
 			     saved: boolean
 			     row:   PostImportRow | null }> }
 
+const THUMBNAIL_MISSING_WARNING = 'サムネールなし'
+
 const buildDraft = (row: PostImportRow): Draft => ({
     url: row.url,
     title: String (row.attributes.title ?? ''),
@@ -29,6 +33,7 @@ const buildDraft = (row: PostImportRow): Draft => ({
     originalCreatedBefore: String (row.attributes.originalCreatedBefore ?? ''),
     tags: String (row.attributes.tags ?? ''),
     parentPostIds: String (row.attributes.parentPostIds ?? ''),
+    duration: String (row.attributes.duration ?? ''),
     thumbnailFile: row.thumbnailFile })
 
 const buildResetDraft = (row: PostImportRow): Draft => ({
@@ -39,6 +44,7 @@ const buildResetDraft = (row: PostImportRow): Draft => ({
     originalCreatedBefore: String (row.resetSnapshot.attributes.originalCreatedBefore ?? ''),
     tags: String (row.resetSnapshot.attributes.tags ?? ''),
     parentPostIds: String (row.resetSnapshot.attributes.parentPostIds ?? ''),
+    duration: String (row.resetSnapshot.attributes.duration ?? ''),
     thumbnailFile: undefined })
 
 const groupedMessages = (...values: (string[] | undefined)[]): string[] =>
@@ -52,6 +58,8 @@ const sameDraft = (left:  Draft, right: Draft): boolean =>
     && left.originalCreatedBefore === right.originalCreatedBefore
     && left.tags === right.tags
     && left.parentPostIds === right.parentPostIds
+    && left.duration === right.duration
+    && left.thumbnailFile === right.thumbnailFile
 
 const sameProvenance = (
     current: PostImportRow['provenance'],
@@ -73,6 +81,17 @@ const sameWarnings = (
     JSON.stringify (current.fieldWarnings) === JSON.stringify (reset.fieldWarnings)
     && JSON.stringify (current.baseWarnings) === JSON.stringify (reset.baseWarnings)
 
+const thumbnailWarnings = (
+    messages:       string[] | undefined,
+    thumbnailBase:  string,
+    thumbnailFile:  File | undefined,
+): string[] => {
+  const others = (messages ?? []).filter (message => message !== THUMBNAIL_MISSING_WARNING)
+  return hasThumbnailBaseValue (thumbnailBase) || thumbnailFile != null
+      ? others
+      : [...new Set ([...others, THUMBNAIL_MISSING_WARNING])]
+}
+
 
 const PostImportRowForm: FC<Props> = (
     { row,
@@ -85,8 +104,6 @@ const PostImportRowForm: FC<Props> = (
   const [resetRequested, setResetRequested] = useState (false)
   const [committedThumbnailBase, setCommittedThumbnailBase] = useState (
       () => String (row.attributes.thumbnailBase ?? ''))
-  const [thumbnailObjectUrl, setThumbnailObjectUrl] = useState<string | undefined> (
-      () => row.thumbnailObjectUrl)
 
   useEffect (() => {
     const nextDraft = buildDraft (row)
@@ -94,18 +111,17 @@ const PostImportRowForm: FC<Props> = (
     setMessageRow (null)
     setResetRequested (false)
     setCommittedThumbnailBase (String (row.attributes.thumbnailBase ?? ''))
-    setThumbnailObjectUrl (row.thumbnailObjectUrl)
   }, [row])
 
-  useEffect (() => () => {
-    if (thumbnailObjectUrl != null)
-      URL.revokeObjectURL (thumbnailObjectUrl)
-  }, [thumbnailObjectUrl])
-
   const displayRow = messageRow ?? row
   const resetDraft = useMemo (
       () => buildResetDraft (row),
       [row])
+  const durationVisible = hasVideoTag (draft.tags)
+  const currentThumbnailWarnings = thumbnailWarnings (
+      displayRow.fieldWarnings.thumbnailBase,
+      draft.thumbnailBase,
+      draft.thumbnailFile)
   const resetDisabled =
       saving
       || (sameDraft (draft, resetDraft)
@@ -129,7 +145,6 @@ const PostImportRowForm: FC<Props> = (
 
     const confirmed = await controls.confirm ({
 	title: '変更をリセットしますか?',
-	description: '現在の URL に対する自動取得直後の内容へ戻します．',
 	confirmText: 'リセット',
 	cancelText: '取消',
 	variant: 'danger' })
@@ -140,11 +155,8 @@ const PostImportRowForm: FC<Props> = (
     setResetRequested (true)
     setMessageRow (null)
     setCommittedThumbnailBase (resetDraft.thumbnailBase)
-    if (thumbnailObjectUrl != null)
-      URL.revokeObjectURL (thumbnailObjectUrl)
-    setThumbnailObjectUrl (undefined)
     return false
-  }, [controls, resetDisabled, resetDraft, thumbnailObjectUrl])
+  }, [controls, resetDisabled, resetDraft])
 
   const save = useCallback (async (): Promise<boolean> => {
     setSaving (true)
@@ -184,7 +196,11 @@ const PostImportRowForm: FC<Props> = (
 	    <div className="grid gap-6 md:grid-cols-[7rem_minmax(0,1fr)]">
 	      <div className="space-y-3 md:sticky md:top-0 md:self-start">
 		<PostImportThumbnailPreview
-		    url={committedThumbnailBase || thumbnailObjectUrl || ''}
+		    url={committedThumbnailBase}
+		    file={
+			hasThumbnailBaseValue (committedThumbnailBase)
+			? undefined
+			: draft.thumbnailFile}
 		    className="h-28 w-28"/>
 	      </div>
 
@@ -204,40 +220,22 @@ const PostImportRowForm: FC<Props> = (
 			      label="サムネール"
 			      value={draft.thumbnailBase}
 			      disabled={saving}
-			      warnings={displayRow.fieldWarnings.thumbnailBase}
+			      warnings={currentThumbnailWarnings}
 			      errors={groupedMessages (
 				  displayRow.validationErrors.thumbnailBase,
 				  displayRow.importErrors?.thumbnailBase)}
 			      onBlur={() => {
-				if (draft.thumbnailBase !== committedThumbnailBase)
+				if (draft.thumbnailBase.trim () !== committedThumbnailBase.trim ())
 				  setCommittedThumbnailBase (draft.thumbnailBase)
 			      }}
-			      onChange={value => {
-				if (value && thumbnailObjectUrl != null)
-				  {
-				    URL.revokeObjectURL (thumbnailObjectUrl)
-				    setThumbnailObjectUrl (undefined)
-				    update ('thumbnailFile', undefined)
-				  }
-				update ('thumbnailBase', value)
-			      }}/>
-			  {!(draft.thumbnailBase) && (
+			      onChange={value => update ('thumbnailBase', value)}/>
+			  {!(hasThumbnailBaseValue (draft.thumbnailBase)) && (
 			      <input
 				  type="file"
 				  accept="image/*"
 				  disabled={saving}
 				  onChange={event => {
 				    const file = event.target.files?.[0]
-				    if (thumbnailObjectUrl != null)
-				      URL.revokeObjectURL (thumbnailObjectUrl)
-				    if (file == null)
-				      {
-					setThumbnailObjectUrl (undefined)
-					update ('thumbnailFile', undefined)
-					return
-				      }
-				    const objectUrl = URL.createObjectURL (file)
-				    setThumbnailObjectUrl (objectUrl)
 				    update ('thumbnailFile', file)
 				  }}/>)}
 			</>}
@@ -283,7 +281,18 @@ const PostImportRowForm: FC<Props> = (
 			    disabled: saving,
 			    errors: groupedMessages (
 				displayRow.validationErrors.parentPostIds,
-				displayRow.importErrors?.parentPostIds) } }}/>
+				displayRow.importErrors?.parentPostIds) } }}
+		    extraFields={
+			durationVisible
+			? (
+			    <PostDurationField
+				value={draft.duration}
+				onChange={value => update ('duration', value)}
+				disabled={saving}
+				errors={groupedMessages (
+				    displayRow.validationErrors.videoMs,
+				    displayRow.importErrors?.videoMs)}/>)
+			: null}/>
 		<FieldWarning messages={displayRow.baseWarnings}/>
 		<FieldError messages={displayRow.validationErrors.base}/>
 		<FieldError messages={displayRow.importErrors?.base}/>

frontend/src/components/posts/import/PostImportRowSummary.tsx

@@ -3,6 +3,7 @@ import { Button } from '@/components/ui/button'
 import PostImportThumbnailPreview from '@/components/posts/import/PostImportThumbnailPreview'
 import PostImportStatusBadge from '@/components/posts/import/PostImportStatusBadge'
 import { displayPostImportStatus } from '@/components/posts/import/postImportRowStatus'
+import { hasVideoTag } from '@/lib/postImportSession'
 import { canEditReviewRow, canRetryResultRow } from '@/lib/postImportSession'
 import { cn, originalCreatedAtString } from '@/lib/utils'
 
@@ -54,6 +55,8 @@ const PostImportRowSummary: FC<Props> = (
   const retryAllowed = onRetry != null && canRetryResultRow (row)
   const skipChecked = row.skipReason === 'manual'
   const rowNumber = displayNumber ?? row.sourceRow
+  const duration = String (row.attributes.duration ?? '')
+  const showDuration = hasVideoTag (row.attributes.tags) && duration !== ''
   const skipControl = showSkipToggle
       ? (
 	  <label className="flex items-center gap-2 text-sm">
@@ -78,10 +81,11 @@ const PostImportRowSummary: FC<Props> = (
           </div>
           <PostImportThumbnailPreview
               url={String (row.attributes.thumbnailBase ?? '')}
+              file={row.thumbnailFile}
               className="h-16 w-16"/>
           <div className="min-w-0 space-y-1">
             <div className="line-clamp-2 text-sm font-medium">
-              {String (row.attributes.title ?? '') || '（タイトル未取得）'}
+              {String (row.attributes.title ?? '')}
             </div>
             <div className="truncate text-xs text-neutral-600 dark:text-neutral-300">
               {row.url}
@@ -93,6 +97,10 @@ const PostImportRowSummary: FC<Props> = (
             <div className="text-xs text-neutral-500 dark:text-neutral-400">
               {summaryDate (row)}
             </div>
+            {showDuration && (
+                <div className="text-xs text-neutral-500 dark:text-neutral-400">
+                  動画時間 {duration}
+                </div>)}
             {warning && (
                 <div className="text-xs text-amber-700 dark:text-amber-200">
                   {warning}
@@ -133,10 +141,11 @@ const PostImportRowSummary: FC<Props> = (
           <div className="flex items-start gap-3">
             <PostImportThumbnailPreview
                 url={String (row.attributes.thumbnailBase ?? '')}
+                file={row.thumbnailFile}
                 className="h-20 w-20 shrink-0"/>
             <div className="min-w-0 flex-1 space-y-2">
               <div className="line-clamp-2 text-sm font-medium">
-                {String (row.attributes.title ?? '') || '（タイトル未取得）'}
+                {String (row.attributes.title ?? '')}
               </div>
               <div className="truncate text-xs text-neutral-600 dark:text-neutral-300">
                 {row.url}
@@ -151,6 +160,10 @@ const PostImportRowSummary: FC<Props> = (
               <div className="text-xs text-neutral-500 dark:text-neutral-400">
                 {summaryDate (row)}
               </div>
+              {showDuration && (
+                  <div className="text-xs text-neutral-500 dark:text-neutral-400">
+                    動画時間 {duration}
+                  </div>)}
               {warning && (
                   <div className="text-xs text-amber-700 dark:text-amber-200">
                     {warning}

frontend/src/components/posts/import/PostImportStatusBadge.tsx

@@ -11,12 +11,16 @@ type Props = {
 const LABELS: Record<PostImportBadgeValue, string> = {
     ready: '登録可能',
     warning: '警告',
-    skipped: 'スキップ' }
+    skipped: 'スキップ',
+    created: '登録済み',
+    failed: '登録失敗' }
 
 const TONES: Record<PostImportBadgeValue, StatusBadgeTone> = {
     ready: 'success',
     warning: 'warning',
-    skipped: 'neutral' }
+    skipped: 'neutral',
+    created: 'success',
+    failed: 'warning' }
 
 
 const PostImportStatusBadge: FC<Props> = ({ value }) => (

frontend/src/components/posts/import/PostImportThumbnailPreview.tsx

@@ -4,17 +4,20 @@ import type { FC } from 'react'
 
 type Props = {
   url:        string
+  file?:      File
   alt?:       string
   className?: string }
 
 
 const PostImportThumbnailPreview: FC<Props> = (
     { url,
+      file,
       alt = 'サムネール',
       className = 'h-16 w-16' },
 ) => (
     <PostThumbnailPreview
         url={url}
+        file={file}
         alt={alt}
         className={className}
         referrerPolicy="no-referrer"/>)

frontend/src/components/posts/import/postImportRowStatus.ts

@@ -1,6 +1,11 @@
 import type { PostImportRow } from '@/lib/postImportSession'
 
-export type PostImportDisplayStatus = 'ready' | 'skipped' | 'warning'
+export type PostImportDisplayStatus =
+    'ready'
+    | 'skipped'
+    | 'warning'
+    | 'created'
+    | 'failed'
 
 export type PostImportBadgeValue = PostImportDisplayStatus
 
@@ -13,10 +18,11 @@ export const displayPostImportStatus = (
 ): PostImportDisplayStatus | null =>
     (row.skipReason != null || row.importStatus === 'skipped')
     ? 'skipped'
-    : ((Object.keys (row.validationErrors ?? { }).length > 0
-	|| row.importStatus === 'failed'
-	|| row.importStatus === 'created')
-       ? null
-       : ((hasWarnings (row) || row.status === 'warning')
-	  ? 'warning'
-	  : 'ready'))
+    : (row.importStatus === 'created')
+      ? 'created'
+      : ((Object.keys (row.validationErrors ?? { }).length > 0
+	  || row.importStatus === 'failed')
+         ? 'failed'
+         : ((hasWarnings (row) || row.status === 'warning')
+	    ? 'warning'
+	    : 'ready'))

frontend/src/lib/postImportRows.ts

@@ -4,6 +4,13 @@ import type { PostImportEditableDraft,
 
 const THUMBNAIL_MISSING_WARNING = 'サムネールなし'
 
+export const hasThumbnailBaseValue = (value: unknown): boolean =>
+    typeof value === 'string' && value.trim () !== ''
+
+export const hasVideoTag = (value: unknown): boolean =>
+    typeof value === 'string'
+    && value.split (/\s+/).includes ('動画')
+
 export const isExistingSkipRow = (row: PostImportRow): boolean =>
     row.skipReason === 'existing'
 
@@ -64,7 +71,7 @@ const deduped = (values: string[]): string[] =>
 const thumbnailWarnings = (row: PostImportRow): string[] => {
     const current = row.fieldWarnings.thumbnailBase ?? []
     const others = current.filter (message => message !== THUMBNAIL_MISSING_WARNING)
-    return row.attributes.thumbnailBase || row.thumbnailFile != null
+    return hasThumbnailBaseValue (row.attributes.thumbnailBase) || row.thumbnailFile != null
         ? others
         : deduped ([...others, THUMBNAIL_MISSING_WARNING])
 }
@@ -168,6 +175,14 @@ export const resultRowWarnings = (row: PostImportRow): string[] =>
         ...Object.values (row.fieldWarnings ?? { }).flat (),
         ...row.baseWarnings])]
 
+
+const isManualChange = (
+    current: unknown,
+    next:    string,
+): boolean =>
+    next !== String (current ?? '')
+
+
 export const buildNextEditedRow = (
     editingRow:  PostImportRow,
     draft:       PostImportEditableDraft,
@@ -183,16 +198,22 @@ export const buildNextEditedRow = (
 	['thumbnailBase', draft.thumbnailBase],
 	['originalCreatedFrom', draft.originalCreatedFrom],
 	['originalCreatedBefore', draft.originalCreatedBefore],
+	['duration', draft.duration],
 	['parentPostIds', draft.parentPostIds]] as const
     draftFields.forEach (([field, value]) => {
 	nextAttributes[field] = value
 	nextProvenance[field] =
-	    value !== String (editingRow.attributes[field] ?? '')
+	    isManualChange (editingRow.attributes[field], value)
 	    ? 'manual'
 	    : (editingRow.provenance[field] ?? 'automatic')
     })
+    if (nextProvenance.duration === 'manual')
+      {
+	nextAttributes.videoMs = ''
+	nextProvenance.videoMs = 'manual'
+      }
     nextAttributes.tags = draft.tags
-    if (draft.tags !== String (editingRow.attributes.tags ?? ''))
+    if (isManualChange (editingRow.attributes.tags, draft.tags))
       {
 	nextProvenance.tags = 'manual'
 	nextTagSources.manual = draft.tags

frontend/src/lib/postImportStorage.ts

@@ -25,6 +25,31 @@ const ATTRIBUTE_KEYS = [
 const PROVENANCE_KEYS = [...ATTRIBUTE_KEYS, 'url'] as const
 const TAG_SOURCE_KEYS = ['automatic', 'manual'] as const
 const WARNING_KEYS = [...ATTRIBUTE_KEYS, 'url'] as const
+const ROW_KEYS = [
+    'sourceRow',
+    'url',
+    'attributes',
+    'fieldWarnings',
+    'baseWarnings',
+    'validationErrors',
+    'importErrors',
+    'provenance',
+    'tagSources',
+    'status',
+    'skipReason',
+    'existingPostId',
+    'existingPost',
+    'metadataUrl',
+    'resetSnapshot',
+    'createdPostId',
+    'importStatus',
+    'recoverable'] as const
+const SESSION_KEYS = [
+    'version',
+    'expiresAt',
+    'source',
+    'rows',
+    'repairMode'] as const
 
 
 const isPlainObject = (value: unknown): value is Record<string, unknown> =>
@@ -220,10 +245,110 @@ const sanitiseExistingPost = (value: unknown): PostImportExistingPost | undefine
         thumbnailUrl: value.thumbnailUrl as string | undefined }
 }
 
+const recalculateThumbnailWarning = (row: PostImportRow): PostImportRow => {
+    const others = (row.fieldWarnings.thumbnailBase ?? []).filter (
+	key => key !== 'サムネールなし')
+    const thumbnailBasePresent =
+	typeof row.attributes.thumbnailBase === 'string'
+	&& row.attributes.thumbnailBase.trim () !== ''
+
+    return {
+        ...row,
+        fieldWarnings: {
+	    ...row.fieldWarnings,
+	    thumbnailBase:
+		thumbnailBasePresent
+		? others
+		: [...new Set ([...others, 'サムネールなし'])] } }
+}
+
+const serialiseExistingPost = (value: PostImportExistingPost | undefined) =>
+    value == null
+    ? undefined
+    : {
+	 id: value.id,
+	 title: value.title,
+	 url: value.url,
+	 thumbnailUrl: value.thumbnailUrl }
+
+const serialiseResetSnapshot = (value: PostImportResetSnapshot) => ({
+    url: value.url,
+    attributes: Object.fromEntries (
+	Object.entries (value.attributes).map (([key, entry]) => [key, entry])),
+    provenance: Object.fromEntries (
+	Object.entries (value.provenance).map (([key, entry]) => [key, entry])),
+    tagSources: {
+	automatic: value.tagSources.automatic,
+	manual: value.tagSources.manual },
+    fieldWarnings: Object.fromEntries (
+	Object.entries (value.fieldWarnings).map (([key, entry]) => [key, [...entry]])),
+    baseWarnings: [...value.baseWarnings],
+    metadataUrl: value.metadataUrl })
+
+export const serialisePostImportRow = (row: PostImportRow) => {
+    const thumbnailBaseWarnings = (() => {
+      const others = (row.fieldWarnings.thumbnailBase ?? []).filter (
+	  message => message !== 'サムネールなし')
+      const thumbnailBasePresent =
+	  typeof row.attributes.thumbnailBase === 'string'
+	  && row.attributes.thumbnailBase.trim () !== ''
+      return thumbnailBasePresent
+	  ? others
+	  : [...new Set ([...others, 'サムネールなし'])]
+    }) ()
+
+    return {
+	sourceRow: row.sourceRow,
+	url: row.url,
+	attributes: Object.fromEntries (
+	    Object.entries (row.attributes).map (([key, entry]) => [key, entry])),
+	fieldWarnings: Object.fromEntries (
+	    Object.entries ({
+		...row.fieldWarnings,
+		thumbnailBase: thumbnailBaseWarnings }).map (([key, entry]) => [key, [...entry]])),
+	baseWarnings: [...row.baseWarnings],
+	validationErrors: Object.fromEntries (
+	    Object.entries (row.validationErrors).map (([key, entry]) => [key, [...entry]])),
+	importErrors:
+	    row.importErrors == null
+	    ? undefined
+	    : Object.fromEntries (
+		Object.entries (row.importErrors).map (([key, entry]) => [key, [...entry]])),
+	provenance: Object.fromEntries (
+	    Object.entries (row.provenance).map (([key, entry]) => [key, entry])),
+	tagSources:
+	    row.tagSources == null
+	    ? undefined
+	    : {
+		automatic: row.tagSources.automatic,
+		manual: row.tagSources.manual },
+	status: row.status,
+	skipReason: row.skipReason,
+	existingPostId: row.existingPostId,
+	existingPost: serialiseExistingPost (row.existingPost),
+	metadataUrl: row.metadataUrl,
+	resetSnapshot: serialiseResetSnapshot (row.resetSnapshot),
+	createdPostId: row.createdPostId,
+	importStatus: row.importStatus,
+	recoverable: row.recoverable }
+}
+
+export const serialisePostImportRows = (rows: PostImportRow[]) =>
+    rows.map (row => serialisePostImportRow (row))
+
+export const serialisedPostImportRowsEqual = (
+    left:  PostImportRow[],
+    right: PostImportRow[],
+): boolean =>
+    JSON.stringify (serialisePostImportRows (left))
+    === JSON.stringify (serialisePostImportRows (right))
+
 
 const sanitiseRow = (value: unknown): PostImportRow | null => {
     if (!(isPlainObject (value)))
       return null
+    if (!(hasOnlyKeys (value, ROW_KEYS)))
+      return null
     if (!(Number.isInteger (value.sourceRow)) || Number (value.sourceRow) <= 0)
       return null
     if (typeof value.url !== 'string')
@@ -321,6 +446,8 @@ const sanitiseRow = (value: unknown): PostImportRow | null => {
 const sanitiseSession = (value: unknown): PostImportSession | null => {
     if (!(isPlainObject (value)))
       return null
+    if (!(hasOnlyKeys (value, SESSION_KEYS)))
+      return null
     if (value.version !== SESSION_VERSION || !(Array.isArray (value.rows)))
       return null
     if (typeof value.expiresAt !== 'string' || isExpiredSession (value.expiresAt))
@@ -334,7 +461,7 @@ const sanitiseSession = (value: unknown): PostImportSession | null => {
         version: SESSION_VERSION,
         expiresAt: value.expiresAt,
         source: typeof value.source === 'string' ? value.source : '',
-        rows: rows as PostImportRow[],
+        rows: (rows as PostImportRow[]).map (row => recalculateThumbnailWarning (row)),
         repairMode: value.repairMode === 'failed' ? 'failed' : 'all' }
 }
 
@@ -438,7 +565,9 @@ export const savePostImportSession = (
     return writeStorage (
         sessionKey (validatedId),
         JSON.stringify ({
-            ...session,
+            source: session.source,
+            rows: serialisePostImportRows (session.rows),
+            repairMode: session.repairMode,
             version: SESSION_VERSION,
             expiresAt: new Date (Date.now () + SESSION_MAX_AGE_MS).toISOString () }),
         onError)

frontend/src/lib/postImportTypes.ts

@@ -43,8 +43,7 @@ export type PostImportRow = {
     createdPostId?:    number
     importStatus?:     PostImportStatus
     recoverable?:      boolean
-    thumbnailFile?:    File
-    thumbnailObjectUrl?: string }
+    thumbnailFile?:    File }
 
 export type PostImportResultRow =
     | {
@@ -88,6 +87,7 @@ export type PostImportEditableDraft = {
     thumbnailBase:         string
     originalCreatedFrom:   string
     originalCreatedBefore: string
+    duration:              string
     tags:                  string
     parentPostIds:         string
     thumbnailFile?:        File }

frontend/src/lib/postNewQueryState.ts

@@ -237,6 +237,7 @@ const manualFields = (row: PostImportRow): string[] =>
      'thumbnailBase',
      'originalCreatedFrom',
      'originalCreatedBefore',
+     'duration',
      'tags',
      'parentPostIds']
     .filter (field => row.provenance[field] === 'manual')
@@ -268,8 +269,8 @@ const buildRow = (state: FullRowState): PostImportRow => {
       thumbnailBase: manual.has ('thumbnailBase') ? 'manual' : 'automatic',
       originalCreatedFrom: manual.has ('originalCreatedFrom') ? 'manual' : 'automatic',
       originalCreatedBefore: manual.has ('originalCreatedBefore') ? 'manual' : 'automatic',
-      videoMs: 'automatic',
-      duration: 'automatic',
+      videoMs: manual.has ('duration') ? 'manual' : 'automatic',
+      duration: manual.has ('duration') ? 'manual' : 'automatic',
       tags: manual.has ('tags') ? 'manual' : 'automatic',
       parentPostIds: manual.has ('parentPostIds') ? 'manual' : 'automatic' }
   const tagSources = provenance.tags === 'manual'
@@ -280,7 +281,7 @@ const buildRow = (state: FullRowState): PostImportRow => {
       thumbnailBase: state.thumbnail_base,
       originalCreatedFrom: state.original_created_from,
       originalCreatedBefore: state.original_created_before,
-      videoMs: state.video_ms,
+      videoMs: manual.has ('duration') ? '' : state.video_ms,
       duration: state.duration,
       tags: state.tags,
       parentPostIds: state.parent_post_ids }
@@ -651,6 +652,7 @@ export const hasPostNewReviewState = (search: string): boolean => {
       || params.has ('urls')
       || params.has ('meta')
       || params.has ('url')
+      || parsePostNewSessionId (search) != null
 }
 
 

frontend/src/pages/posts/PostImportReviewPage.tsx

@@ -29,6 +29,7 @@ import {
     clearPostImportSession,
     clearPostImportSourceDraft,
     generatePostImportSessionId,
+    hasThumbnailBaseValue,
     initialisePreviewRows,
     isCompletedReviewRow,
     isExistingSkipRow,
@@ -41,6 +42,7 @@ import {
     reviewSummaryCounts,
     retryImportRow,
     loadPostImportSession,
+    serialisedPostImportRowsEqual,
     savePostImportSession,
 } from '@/lib/postImportSession'
 import { useClientBehaviourSettings } from '@/lib/useClientBehaviourSettings'
@@ -125,7 +127,7 @@ const buildDryRunFormData = (row: PostImportRow): FormData => {
       String (row.attributes.originalCreatedBefore ?? ''))
   formData.append ('video_ms', String (row.attributes.videoMs ?? ''))
   formData.append ('duration', String (row.attributes.duration ?? ''))
-  if (!(row.attributes.thumbnailBase) && row.thumbnailFile != null)
+  if (!(hasThumbnailBaseValue (row.attributes.thumbnailBase)) && row.thumbnailFile != null)
     formData.append ('thumbnail', row.thumbnailFile)
   return formData
 }
@@ -174,6 +176,12 @@ const indexedBulkResults = (
 ): PostImportResultRow[] =>
     rows.map ((row, index) => {
       const result = results[index]
+      const errors =
+	  result?.baseErrors?.length
+	  ? {
+	      ...(result.errors ?? { }),
+	      base: [...new Set ([...(result.errors?.base ?? []), ...result.baseErrors])] }
+	  : result?.errors
       if (result?.status === 'created' && result.post != null)
         {
           return {
@@ -182,7 +190,7 @@ const indexedBulkResults = (
               post: result.post,
               fieldWarnings: result.fieldWarnings,
               baseWarnings: result.baseWarnings,
-              errors: result.errors }
+              errors }
         }
       if (result?.status === 'skipped' && result.existingPost != null)
         {
@@ -193,52 +201,28 @@ const indexedBulkResults = (
               existingPost: result.existingPost,
               fieldWarnings: result.fieldWarnings,
               baseWarnings: result.baseWarnings,
-              errors: result.errors }
+              errors }
         }
       return {
           sourceRow: row.sourceRow,
           status: 'failed',
           fieldWarnings: result?.fieldWarnings,
           baseWarnings: result?.baseWarnings,
-          errors: result?.errors,
+          errors,
           recoverable: result?.recoverable }
     })
 
-const serialisableRowJson = (row: PostImportRow): string =>
-    JSON.stringify ({
-	url: row.url,
-	sourceRow: row.sourceRow,
-	attributes: row.attributes,
-	fieldWarnings: row.fieldWarnings,
-	baseWarnings: row.baseWarnings,
-	validationErrors: row.validationErrors,
-	importErrors: row.importErrors,
-	provenance: row.provenance,
-	tagSources: row.tagSources,
-	status: row.status,
-	skipReason: row.skipReason,
-	existingPostId: row.existingPostId,
-	existingPost: row.existingPost,
-	metadataUrl: row.metadataUrl,
-	resetSnapshot: row.resetSnapshot,
-	createdPostId: row.createdPostId,
-	importStatus: row.importStatus,
-	recoverable: row.recoverable })
-
-const serialisableRowsEqual = (
-    left:  PostImportRow[],
-    right: PostImportRow[],
-): boolean =>
-    left.length === right.length
-    && left.every ((row, index) =>
-	serialisableRowJson (row) === serialisableRowJson (right[index]))
-
 const mergePreviewRow = (
     currentRow: PostImportRow,
     preview:    PreviewResponse,
 ): PostImportRow => {
   const nextRow: PostImportRow = {
       ...currentRow,
+      attributes: { ...currentRow.attributes },
+      provenance: { ...currentRow.provenance },
+      tagSources: {
+	  automatic: currentRow.tagSources?.automatic ?? '',
+	  manual: currentRow.tagSources?.manual ?? '' },
       url: preview.url,
       fieldWarnings: preview.fieldWarnings ?? { },
       baseWarnings: preview.baseWarnings ?? [],
@@ -267,9 +251,7 @@ const mergePreviewRow = (
   if (currentRow.provenance.tags !== 'manual')
     {
       nextRow.attributes.tags = preview.tags ?? ''
-      nextRow.tagSources = {
-	  automatic: preview.tags ?? '',
-	  manual: currentRow.tagSources?.manual ?? '' }
+      nextRow.tagSources.automatic = preview.tags ?? ''
     }
   if (currentRow.provenance.videoMs !== 'manual')
     nextRow.attributes.videoMs = preview.videoMs ?? ''
@@ -296,7 +278,7 @@ const buildBulkFormData = (rows: PostImportRow[]): FormData => {
 	      video_ms: row.attributes.videoMs ?? '',
 	      duration: row.attributes.duration ?? '' }))))
   rows.forEach ((row, index) => {
-    if (!(row.attributes.thumbnailBase) && row.thumbnailFile != null)
+    if (!(hasThumbnailBaseValue (row.attributes.thumbnailBase)) && row.thumbnailFile != null)
       formData.append (`thumbnails[${ index }]`, row.thumbnailFile)
   })
   return formData
@@ -380,10 +362,10 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
     const canRecoverFromUrlOnly = serialised.complete
     if (!(canRecoverFromUrlOnly)
         && (!(saved))
-        && !(serialisableRowsEqual (loadedSession?.rows ?? [], nextSession.rows)))
+        && !(serialisedPostImportRowsEqual (loadedSession?.rows ?? [], nextSession.rows)))
       return null
     if (saved
-        && !(serialisableRowsEqual (loadedSession?.rows ?? [], nextSession.rows)))
+        && !(serialisedPostImportRowsEqual (loadedSession?.rows ?? [], nextSession.rows)))
       return null
 
     const persistedSession = buildSession (nextSession.rows)
@@ -425,6 +407,11 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
             return
 
           const baseRow = baseSession.rows[index]
+          if (baseRow.skipReason === 'manual'
+              || baseRow.importStatus === 'created'
+              || baseRow.importStatus === 'skipped'
+              || isNonRecoverableFailedRow (baseRow))
+            continue
           const controller = new AbortController ()
           controllers.add (controller)
           try
@@ -441,10 +428,8 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
             if (currentRow == null)
               continue
             const mergedRow = mergePreviewRow (currentRow, preview)
-            const nextRows = replaceImportRow (latestSession.rows, mergedRow)
-            const nextSession = buildSession (nextRows)
-            sessionRef.current = nextSession
-            setSession (nextSession)
+            await persistSession (buildSession (
+                replaceImportRow (latestSession.rows, mergedRow)))
           }
           catch (requestError)
           {
@@ -457,15 +442,6 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
                 row => row.sourceRow === baseRow.sourceRow)
             if (currentRow == null)
               continue
-            const nextRows = replaceImportRow (
-                latestSession.rows,
-                applyThumbnailWarning ({
-                    ...currentRow,
-                    existingPostId: undefined,
-                    existingPost: undefined }))
-            const nextSession = buildSession (nextRows)
-            sessionRef.current = nextSession
-            setSession (nextSession)
             if (!(isApiError (requestError)))
               continue
           }
@@ -481,24 +457,25 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
     }
 
     const hydrate = async () => {
+      const parsedSessionId = parsePostNewSessionId (location.search)
+      const sessionId = parsedSessionId ?? generatePostImportSessionId ()
+      const loadedSession = loadPostImportSession (sessionId)
       const parsed = await parsePostNewState (location.search)
       if (!(active))
 	return
-      if (parsed == null)
+      if (parsed == null && loadedSession == null)
 	{
 	  navigate ('/posts/new', { replace: true })
 	  return
 	}
 
-      const parsedSessionId = parsePostNewSessionId (location.search)
-      const sessionId = parsedSessionId ?? generatePostImportSessionId ()
       sessionIdRef.current = sessionId
-      const loaded = loadPostImportSession (sessionId) ?? buildSession (parsed.rows)
+      const loaded = loadedSession ?? buildSession (parsed?.rows ?? [])
       persistedSearchRef.current = location.search
       sessionRef.current = loaded
       setSession (loaded)
 
-      if (parsed.shortcut)
+      if (loadedSession == null && parsed?.shortcut)
 	{
 	  try
 	  {
@@ -580,7 +557,7 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
 	  return
 	}
 
-      if (parsedSessionId == null)
+      if (loadedSession == null)
 	{
 	  await persistSession (loaded)
 	}
@@ -672,21 +649,28 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
 		    .map (([key, values]) => [key, [...values]])),
 	    baseWarnings: [...row.resetSnapshot.baseWarnings],
 	    metadataUrl: row.resetSnapshot.metadataUrl,
-	    thumbnailFile: undefined,
-	    thumbnailObjectUrl: undefined }
+	    thumbnailFile: undefined }
 	: row
     const urlChanged = draft.url !== baseRow.url
     const nextRow = buildNextEditedRow (baseRow, draft, urlChanged)
+    let candidateRow = nextRow
     try
     {
+      candidateRow =
+	  urlChanged
+	  ? mergePreviewRow (
+	      nextRow,
+	      await apiGet<PreviewResponse> ('/posts/preview', {
+		  params: { url: nextRow.url } }))
+	  : nextRow
       const dryRun = await apiPost<PreviewResponse> (
 	  '/posts?dry=1',
-	  buildDryRunFormData (nextRow))
+	  buildDryRunFormData (candidateRow))
       const latestSession = sessionRef.current
       if (latestSession == null)
 	return { saved: false, row: null }
 
-      const mergedRow = mergeDryRunRow (nextRow, dryRun)
+      const mergedRow = mergeDryRunRow (candidateRow, dryRun)
       const mergedRows = replaceImportRow (latestSession.rows, mergedRow)
       const nextSession = await persistSession (buildSession (mergedRows))
       if (nextSession == null)
@@ -708,7 +692,7 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
 	  && requestError.response?.status === 422)
 	{
 	  const errorRow = {
-	      ...nextRow,
+	      ...candidateRow,
 	      validationErrors: requestError.response.data.errors ?? { },
 	      baseWarnings: [],
 	      fieldWarnings: { },
@@ -731,7 +715,6 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
 
     await dialogue.form ({
 	title: '投稿を編輯',
-	description: `投稿 ${ row.sourceRow } の内容を確認し、必要な項目を編輯してください．`,
 	cancelText: '取消',
 	size: 'large',
 	body: controls => (

frontend/src/pages/posts/PostImportSourcePage.tsx

@@ -24,6 +24,7 @@ import { countImportSourceLines,
 	 loadPostImportSession,
 	 loadPostImportSourceDraft,
 	 resultRepairMode,
+	 serialisedPostImportRowsEqual,
 	 savePostImportSession,
 	 savePostImportSourceDraft,
 	 validateImportSource } from '@/lib/postImportSession'
@@ -143,8 +144,16 @@ const fetchPreviewRows = async (
     rows:        Array<{ sourceRow: number
 			 url:       string }>,
     signal:      AbortSignal,
-): Promise<PostImportRow[]> => {
-  const results: PostImportRow[] = new Array (rows.length)
+): Promise<{
+    rows:    PostImportRow[]
+    issues:  Array<{ sourceRow: number
+		     message:   string
+		     url:       string }>
+}> => {
+  const results: Array<PostImportRow | null> = new Array (rows.length).fill (null)
+  const issues: Array<{ sourceRow: number
+			message:   string
+			url:       string }> = []
   let nextIndex = 0
   const worker = async () => {
     while (nextIndex < rows.length)
@@ -152,44 +161,43 @@ const fetchPreviewRows = async (
       const index = nextIndex
       ++nextIndex
       const row = rows[index]
-      const result = await apiGet<PreviewResponse> ('/posts/preview', {
-	  params: { url: row.url },
-	  signal })
-      results[index] = previewRowFromResult (row.sourceRow, result)
+      try
+      {
+        const result = await apiGet<PreviewResponse> ('/posts/preview', {
+	    params: { url: row.url },
+	    signal })
+        results[index] = previewRowFromResult (row.sourceRow, result)
+      }
+      catch (requestError)
+      {
+        if (signal.aborted)
+          return
+
+        const apiMessage =
+            isApiError<{
+                message?:    string
+                errors?:     Record<string, string[]>
+                baseErrors?: string[]
+            }> (requestError)
+            ? (requestError.response?.data?.errors?.url?.[0]
+               ?? requestError.response?.data?.message
+               ?? requestError.response?.data?.baseErrors?.[0])
+            : undefined
+        issues.push ({
+	    sourceRow: row.sourceRow,
+	    message: apiMessage ?? '入力を確認してください．',
+	    url: row.url })
+      }
     }
   }
 
   await Promise.all (
       Array.from ({ length: Math.min (4, rows.length) }, () => worker ()))
-  return results
+  return {
+      rows: results.filter ((row): row is PostImportRow => row != null),
+      issues }
 }
 
-const serialisableRowJson = (row: PostImportRow): string =>
-    JSON.stringify ({
-	sourceRow: row.sourceRow,
-	url: row.url,
-	attributes: row.attributes,
-	fieldWarnings: row.fieldWarnings,
-	baseWarnings: row.baseWarnings,
-	validationErrors: row.validationErrors,
-	provenance: row.provenance,
-	tagSources: row.tagSources,
-	status: row.status,
-	skipReason: row.skipReason,
-	existingPostId: row.existingPostId,
-	existingPost: row.existingPost,
-	resetSnapshot: row.resetSnapshot,
-	importStatus: row.importStatus,
-	recoverable: row.recoverable })
-
-const sameRows = (
-    left:  PostImportRow[],
-    right: PostImportRow[],
-): boolean =>
-    left.length === right.length
-    && left.every ((row, index) =>
-	serialisableRowJson (row) === serialisableRowJson (right[index]))
-
 
 const PostImportSourcePage: FC<Props> = ({ user }) => {
   const editable = canEditContent (user)
@@ -269,7 +277,7 @@ const PostImportSourcePage: FC<Props> = ({ user }) => {
       previewController.current?.abort ()
       const controller = new AbortController ()
       previewController.current = controller
-      const rows = await fetchPreviewRows (
+      const previewed = await fetchPreviewRows (
 	  source
 	  .split (/\r\n|\n|\r/)
 	  .map ((line, index) => ({
@@ -277,13 +285,31 @@ const PostImportSourcePage: FC<Props> = ({ user }) => {
 	      url: line.trim () }))
 	  .filter (row => row.url !== ''),
 	  controller.signal)
-      const urlIssues = urlIssuesFromRows (rows, source)
-      if (urlIssues.length > 0)
+      if (previewed.issues.length > 0)
 	{
-	  setSourceIssues (urlIssues)
+	  setSourceIssues (previewed.issues)
 	  return
 	}
-      const nextRows = initialisePreviewRows (rows)
+      const urlIssues = urlIssuesFromRows (previewed.rows, source)
+      const duplicateIssues = Object.entries (
+	  previewed.rows.reduce<Record<string, PostImportRow[]>> ((acc, row) => {
+	    acc[row.url] ||= []
+	    acc[row.url].push (row)
+	    return acc
+	  }, { }))
+	  .flatMap (([, rows]) =>
+	      rows.length < 2
+	      ? []
+	      : rows.map (row => ({
+		  sourceRow: row.sourceRow,
+		  message: 'URL が重複しています．',
+		  url: row.url })))
+      if (urlIssues.length > 0 || duplicateIssues.length > 0)
+	{
+	  setSourceIssues ([...urlIssues, ...duplicateIssues])
+	  return
+	}
+      const nextRows = initialisePreviewRows (previewed.rows)
       const serialised = await serialisePostNewState (nextRows)
       if (serialised == null)
 	return
@@ -297,9 +323,9 @@ const PostImportSourcePage: FC<Props> = ({ user }) => {
       const sessionLoaded = loadPostImportSession (sessionId)
       if (!(serialised.complete)
           && (!(saved))
-          && !(sameRows (sessionLoaded?.rows ?? [], nextRows)))
+          && !(serialisedPostImportRowsEqual (sessionLoaded?.rows ?? [], nextRows)))
 	return
-      if (saved && !(sameRows (sessionLoaded?.rows ?? [], nextRows)))
+      if (saved && !(serialisedPostImportRowsEqual (sessionLoaded?.rows ?? [], nextRows)))
 	return
 
       navigate (appendPostNewSessionId (serialised.path, sessionId))