feat: export currently open temporary chats (#375)

Temporary chats are served by the regular conversation API but are hidden
from the history list and never put their id in the URL. Capture the id from
the /backend-api/f/conversation stream, then export through the existing API
path. Export is blocked with a clear alert until the id has been observed.

---------

Co-authored-by: Pascal Perle <17356275+pperle@users.noreply.github.com>
Co-authored-by: Pionxzh <hi@pionxzh.com>

src/api.ts

@@ -1,6 +1,7 @@
 import urlcat from 'urlcat'
 import { apiUrl, baseUrl } from './constants'
-import { getChatIdFromUrl, getConversationFromSharePage, isSharePage } from './page'
+import { getChatIdFromUrl, getConversationFromSharePage, isSharePage, isTemporaryChat } from './page'
+import { getTemporaryChatId } from './temporaryChat'
 import { blobToDataURL } from './utils/dom'
 import { memorize } from './utils/memorize'
 
@@ -443,6 +444,16 @@ export async function getCurrentChatId(): Promise<string> {
         return `__share__${getChatIdFromUrl()}`
     }
 
+    // A temporary chat is absent from the history list and never puts its id in
+    // the URL, so without this the lookup below would fall through to the most
+    // recent conversation and export the wrong chat. Guarded by
+    // `checkIfTemporaryChatIsExportable` at every export entry point.
+    if (isTemporaryChat()) {
+        const temporaryChatId = getTemporaryChatId()
+        if (!temporaryChatId) throw new Error('No temporary chat id found.')
+        return temporaryChatId
+    }
+
     const chatId = getChatIdFromUrl()
     if (chatId) return chatId
 

src/exporter/html.ts

@@ -4,6 +4,7 @@ import { KEY_SOURCES_ENABLED, KEY_THINKING_ENABLED, KEY_TIMESTAMP_24H, KEY_TIMES
 import i18n from '../i18n'
 import { checkIfConversationStarted, getUserAvatar } from '../page'
 import templateHtml from '../template.html?raw'
+import { checkIfTemporaryChatIsExportable } from '../temporaryChat'
 import { transformContentReferences } from '../utils/citations'
 import { buildZipFileName, downloadFile, getFileNameWithFormat } from '../utils/download'
 import { fromMarkdown, toHtml } from '../utils/markdown'
@@ -20,6 +21,11 @@ export async function exportToHtml(fileNameFormat: string, metaList: ExportMeta[
         return false
     }
 
+    if (!checkIfTemporaryChatIsExportable()) {
+        alert(i18n.t('Temporary chat could not be captured'))
+        return false
+    }
+
     const userAvatar = await getUserAvatar()
 
     const chatId = await getCurrentChatId()

src/exporter/json.ts

@@ -2,6 +2,7 @@ import JSZip from 'jszip'
 import { fetchConversation, getCurrentChatId, processConversation } from '../api'
 import i18n from '../i18n'
 import { checkIfConversationStarted } from '../page'
+import { checkIfTemporaryChatIsExportable } from '../temporaryChat'
 import { convertToOoba, convertToTavern } from '../utils/conversion'
 import { buildJsonBatchFileName, buildZipFileName, downloadFile, getFileNameWithFormat } from '../utils/download'
 import type { ApiConversationWithId } from '../api'
@@ -14,6 +15,11 @@ export async function exportToJson(fileNameFormat: string) {
         return false
     }
 
+    if (!checkIfTemporaryChatIsExportable()) {
+        alert(i18n.t('Temporary chat could not be captured'))
+        return false
+    }
+
     const chatId = await getCurrentChatId()
     const rawConversation = await fetchConversation(chatId, false)
     const conversation = processConversation(rawConversation)
@@ -34,6 +40,11 @@ export async function exportToTavern(fileNameFormat: string) {
         return false
     }
 
+    if (!checkIfTemporaryChatIsExportable()) {
+        alert(i18n.t('Temporary chat could not be captured'))
+        return false
+    }
+
     const chatId = await getCurrentChatId()
     const rawConversation = await fetchConversation(chatId, false)
     const conversation = processConversation(rawConversation)
@@ -51,6 +62,11 @@ export async function exportToOoba(fileNameFormat: string) {
         return false
     }
 
+    if (!checkIfTemporaryChatIsExportable()) {
+        alert(i18n.t('Temporary chat could not be captured'))
+        return false
+    }
+
     const chatId = await getCurrentChatId()
     const rawConversation = await fetchConversation(chatId, false)
     const conversation = processConversation(rawConversation)

src/exporter/markdown.ts

@@ -3,6 +3,7 @@ import { fetchConversation, getCurrentChatId, processConversation, shouldSkipMes
 import { KEY_SOURCES_ENABLED, KEY_THINKING_ENABLED, KEY_TIMESTAMP_24H, KEY_TIMESTAMP_ENABLED, KEY_TIMESTAMP_MARKDOWN, baseUrl } from '../constants'
 import i18n from '../i18n'
 import { checkIfConversationStarted } from '../page'
+import { checkIfTemporaryChatIsExportable } from '../temporaryChat'
 import { transformContentReferences } from '../utils/citations'
 import { buildZipFileName, downloadFile, getFileNameWithFormat } from '../utils/download'
 import { fromMarkdown, toMarkdown } from '../utils/markdown'
@@ -19,6 +20,11 @@ export async function exportToMarkdown(fileNameFormat: string, metaList: ExportM
         return false
     }
 
+    if (!checkIfTemporaryChatIsExportable()) {
+        alert(i18n.t('Temporary chat could not be captured'))
+        return false
+    }
+
     const chatId = await getCurrentChatId()
     const rawConversation = await fetchConversation(chatId, true)
     const enableThinking = ScriptStorage.get<boolean>(KEY_THINKING_ENABLED) ?? false

src/exporter/text.ts

@@ -1,6 +1,7 @@
 import { fetchConversation, getCurrentChatId, processConversation, shouldSkipMessageInExport } from '../api'
 import i18n from '../i18n'
 import { checkIfConversationStarted } from '../page'
+import { checkIfTemporaryChatIsExportable } from '../temporaryChat'
 import { transformContentReferences } from '../utils/citations'
 import { copyToClipboard } from '../utils/clipboard'
 import { flatMap, fromMarkdown, toMarkdown } from '../utils/markdown'
@@ -14,6 +15,11 @@ export async function exportToText() {
         return false
     }
 
+    if (!checkIfTemporaryChatIsExportable()) {
+        alert(i18n.t('Temporary chat could not be captured'))
+        return false
+    }
+
     const chatId = await getCurrentChatId()
     // All image in text output will be replaced with `[image]`
     // So we don't need to waste time to download them

src/locales/en.json

@@ -44,6 +44,7 @@
   "Conversation Delete Alert": "Are you sure you want to delete all selected conversations?",
   "Conversation Deleted Message": "All selected conversations have been deleted. Please refresh the page to see the changes.",
   "Please start a conversation first": "Please start a conversation first.",
+  "Temporary chat could not be captured": "This temporary chat could not be read. It may have started before the exporter was loaded. You can still export it as a PNG screenshot.",
   "Select Project": "Select Project",
   "(no project)": "(no project)",
   "Export All Limit": "Export All Limit",

src/locales/es.json

@@ -44,6 +44,7 @@
   "Conversation Delete Alert": "¿Estás seguro que quieres borrar todas las conversaciones seleccionadas?",
   "Conversation Deleted Message": "Todos las conversaciones seleccionadas se han borrado. Por favor refresca la página para ver los cambios.",
   "Please start a conversation first": "Por favor empieza una conversación antes.",
+  "Temporary chat could not be captured": "No se pudo leer este chat temporal. Es posible que haya comenzado antes de que se cargara el exportador. Aún puedes exportarlo como una captura de pantalla PNG.",
   "Select Project": "Seleccionar proyecto",
   "(no project)": "(sin proyecto)",
   "Export All Limit": "Límite de Exportar Todos",

src/locales/fr.json

@@ -44,6 +44,7 @@
   "Conversation Delete Alert": "Êtes-vous sûr de vouloir supprimer toutes les conversations sélectionnées ?",
   "Conversation Deleted Message": "Toutes les conversations sélectionnées ont été supprimées. Veuillez actualiser la page pour voir les changements.",
   "Please start a conversation first": "Veuillez commencer une conversation d'abord.",
+  "Temporary chat could not be captured": "Ce chat éphémère n'a pas pu être lu. Il a peut-être commencé avant le chargement de l'exportateur. Vous pouvez toujours l'exporter en capture d'écran PNG.",
   "Select Project": "Sélectionner un projet",
   "(no project)": "(aucun projet)",
   "Export All Limit": "Limite d'Exportation Multiple",

src/locales/id.json

@@ -44,6 +44,7 @@
   "Conversation Delete Alert": "Apakah Anda yakin ingin menghapus semua percakapan yang dipilih?",
   "Conversation Deleted Message": "Semua percakapan yang dipilih telah dihapus. Harap segarkan halaman untuk melihat perubahan.",
   "Please start a conversation first": "Harap mulai percakapan terlebih dahulu.",
+  "Temporary chat could not be captured": "Obrolan sementara ini tidak dapat dibaca. Mungkin obrolan dimulai sebelum pengekspor dimuat. Anda masih dapat mengekspornya sebagai tangkapan layar PNG.",
   "Select Project": "Pilih Proyek",
   "(no project)": "(tidak ada proyek)",
   "Export All Limit": "Batas Ekspor Semua",

src/locales/jp.json

@@ -44,6 +44,7 @@
   "Conversation Delete Alert": "選択したすべての会話を削除してもよろしいですか？",
   "Conversation Deleted Message": "選択したすべての会話が削除されました。変更を表示するには、ページを更新してください。",
   "Please start a conversation first": "まず会話を開始してください。",
+  "Temporary chat could not be captured": "この一時チャットを読み取れませんでした。エクスポーターが読み込まれる前に開始された可能性があります。PNG スクリーンショットとしてエクスポートすることは可能です。",
   "Select Project": "プロジェクトを選択",
   "(no project)": "（プロジェクトなし）",
   "Export All Limit": "すべてエクスポートの上限",

src/locales/ru.json

@@ -44,6 +44,7 @@
   "Conversation Delete Alert": "Вы уверены, что хотите удалить все выбранные разговоры?",
   "Conversation Deleted Message": "Все выбранные разговоры были удалены. Пожалуйста, обновите страницу, чтобы увидеть изменения.",
   "Please start a conversation first": "Пожалуйста, начните разговор первым.",
+  "Temporary chat could not be captured": "Не удалось прочитать этот временный чат. Возможно, он был начат до загрузки экспортёра. Вы всё ещё можете экспортировать его как PNG-скриншот.",
   "Select Project": "Выберите проект",
   "(no project)": "(нет проекта)",
   "Export All Limit": "Лимит экспорта всех",

src/locales/tr.json

@@ -44,6 +44,7 @@
   "Conversation Delete Alert": "Seçilen tüm konuşmaları silmek istediğinizden emin misiniz?",
   "Conversation Deleted Message": "Seçilen tüm konuşmalar silindi. Değişiklikleri görmek için sayfayı yenileyin.",
   "Please start a conversation first": "Lütfen önce bir konuşma başlatın.",
+  "Temporary chat could not be captured": "Bu geçici sohbet okunamadı. Dışa aktarıcı yüklenmeden önce başlamış olabilir. Yine de PNG ekran görüntüsü olarak dışa aktarabilirsiniz.",
   "Select Project": "Proje Seç",
   "(no project)": "(proje yok)",
   "Export All Limit": "Tümünü Dışa Aktarma Limiti",

src/locales/zh-Hans.json

@@ -44,6 +44,7 @@
   "Conversation Delete Alert": "确定要删除所有选取的对话？",
   "Conversation Deleted Message": "所有所选的对话已删除。请刷新页面。",
   "Please start a conversation first": "请先开始对话。",
+  "Temporary chat could not be captured": "无法读取此临时聊天，它可能在导出工具加载前就已开始。你仍可以将其导出为 PNG 截图。",
   "Select Project": "选择项目",
   "(no project)": "（无项目）",
   "Export All Limit": "批量导出上限",

src/locales/zh-Hant.json

@@ -44,6 +44,7 @@
   "Conversation Delete Alert": "確定要刪除所有選取的對話？",
   "Conversation Deleted Message": "所有選取的對話已刪除。請重新整理頁面。",
   "Please start a conversation first": "請先開始對話。",
+  "Temporary chat could not be captured": "無法讀取此暫存對話，它可能在匯出工具載入前就已開始。你仍可以將其匯出為 PNG 截圖。",
   "Select Project": "選擇專案",
   "(no project)": "（無專案）",
   "Export All Limit": "批量匯出上限",

src/main.tsx

@@ -2,6 +2,7 @@ import { render } from 'preact'
 import sentinel from 'sentinel-js'
 import { fetchConversation, processConversation } from './api'
 import { getChatIdFromUrl, isSharePage } from './page'
+import { watchTemporaryChatId } from './temporaryChat'
 import { Menu } from './ui/Menu'
 import { onloadSafe } from './utils/utils'
 
@@ -11,6 +12,10 @@ import './styles/missing-tailwind.css'
 main()
 
 function main() {
+    // Installed before the page is ready so it is in place by the time the
+    // user can send the first message of a temporary chat.
+    watchTemporaryChatId()
+
     onloadSafe(() => {
         // eslint-disable-next-line no-console
         console.log('[Exporter] Loaded')

src/page.ts

@@ -49,6 +49,17 @@ export function getChatIdFromUrl() {
     return null
 }
 
+/**
+ * Temporary chats are hidden from the history list and their id never reaches
+ * the URL, although the conversation API still serves them once the id is
+ * known (see temporaryChat.ts). Without this check the exporter falls through
+ * to the most recent conversation in the history and silently exports the
+ * wrong chat.
+ */
+export function isTemporaryChat() {
+    return new URLSearchParams(location.search).get('temporary-chat') === 'true'
+}
+
 export function isSharePage() {
     return location.pathname.startsWith('/share')
         && !location.pathname.endsWith('/continue')

src/temporaryChat.ts

@@ -0,0 +1,110 @@
+import { unsafeWindow } from 'vite-plugin-monkey/dist/client'
+import { isTemporaryChat } from './page'
+
+/** The endpoint that streams a message exchange back to the page. */
+const CONVERSATION_STREAM_PATH = '/backend-api/f/conversation'
+const DATA_PREFIX = 'data:'
+/** Give up if the id has not shown up in the first chunks of the stream. */
+const MAX_SCAN_LENGTH = 200_000
+
+let temporaryChatId: string | null = null
+
+export function getTemporaryChatId() {
+    return temporaryChatId
+}
+
+/**
+ * Mirrors `checkIfConversationStarted`: a temporary chat can only be exported
+ * once its id has been observed.
+ */
+export function checkIfTemporaryChatIsExportable() {
+    return !isTemporaryChat() || temporaryChatId !== null
+}
+
+/**
+ * Temporary chats are hidden from the conversation list and their id never
+ * reaches the URL, so there is no way to ask for one by name. They are served
+ * by the regular conversation endpoint once the id is known, and the server
+ * announces that id in the response that streams the reply back to the page,
+ * so record it as it goes past.
+ */
+export function watchTemporaryChatId() {
+    const originalFetch = unsafeWindow.fetch
+
+    unsafeWindow.fetch = async (input, init) => {
+        // `fetch` needs its original receiver, or Chrome throws on invocation.
+        const response = await originalFetch.call(unsafeWindow, input, init)
+        if (!isTemporaryChat() || !response.body) return response
+
+        const url = typeof input === 'string'
+            ? input
+            : input instanceof URL ? input.href : input.url
+        if (!url.includes(CONVERSATION_STREAM_PATH)) return response
+
+        // Read a copy so the page still receives the untouched stream.
+        readConversationId(response.clone())
+
+        return response
+    }
+}
+
+async function readConversationId(response: Response) {
+    const reader = response.body?.getReader()
+    if (!reader) return
+
+    const decoder = new TextDecoder()
+    let buffer = ''
+    let scanned = 0
+
+    try {
+        while (scanned < MAX_SCAN_LENGTH) {
+            const { done, value } = await reader.read()
+            if (done) break
+
+            const chunk = decoder.decode(value, { stream: true })
+            scanned += chunk.length
+            buffer += chunk
+
+            // Hold back the trailing partial line until the next chunk.
+            const lines = buffer.split('\n')
+            buffer = lines.pop() ?? ''
+
+            const conversationId = findConversationId(lines)
+            if (conversationId) {
+                temporaryChatId = conversationId
+                break
+            }
+        }
+    }
+    catch (error) {
+        console.error('[Exporter] Failed to read the temporary chat id', error)
+    }
+    finally {
+        // Release the copy. Cancelling one branch of a teed stream leaves the
+        // branch the page is reading alone.
+        reader.cancel().catch(() => {})
+    }
+}
+
+/**
+ * Read the id off the stream's own events. Only the `conversation_id` field is
+ * taken; the message content the events carry is never inspected or kept.
+ */
+function findConversationId(lines: string[]): string | null {
+    for (const line of lines) {
+        if (!line.startsWith(DATA_PREFIX)) continue
+
+        const payload = line.slice(DATA_PREFIX.length).trim()
+        if (!payload || payload === '[DONE]') continue
+
+        try {
+            const { conversation_id: conversationId } = JSON.parse(payload)
+            if (typeof conversationId === 'string') return conversationId
+        }
+        catch {
+            // Not every event in the stream carries a JSON payload.
+        }
+    }
+
+    return null
+}