feat(ai-chat): persistent history as source of truth — step durability + server export (#183)

The chat lived in inconsistent paradigms (in-memory stream + client export vs.
DB-as-context), which made export flaky and lost the assistant answer if the
process died mid-turn. Make the DB the single source of truth.

A. STEP-GRANULAR DURABILITY (server)
- ai_chat_messages gains a nullable `status` column (migration; NULL = legacy =
  completed). The assistant row is now INSERTED UPFRONT as `status:'streaming'`
  and UPDATEd on every onStepFinish with all finished steps (text + tool calls +
  tool RESULTS), then finalized once to completed/error/aborted on the terminal
  callback. So a process death mid-turn keeps every finished step; a startup
  sweep (OnModuleInit → sweepStreaming) flips any dangling 'streaming' row to
  'aborted'. The write path no longer depends on a live socket.
- Pure exported `flushAssistant(steps, inProgressText, status, extra?)` builds
  the persist payload (metadata.parts byte-identical to the old builder), so a
  future background worker can call the same path. AiChatMessageRepo gains
  `update`, `sweepStreaming`, and `findAllByChat`.
- consumeStream drain, external-MCP client close-once, SSE heartbeat preserved.

B. SERVER-SIDE EXPORT
- New pure `chat-markdown.util.ts` renders Markdown from DB rows ONLY (server
  port of the client builder). Because A persists the in-progress row, the
  export now includes an interrupted turn up to its last finished step (flagged
  "still generating"). `POST /ai-chat/export` (owner-gated via assertOwnedChat,
  workspace-scoped) returns it; `lang` accepts a full client locale tag
  ('en-US'/'ru-RU') and is normalized server-side (normalizeLang) — a strict
  @IsIn(['en','ru']) DTO rejected the real client's i18n.language with a 400,
  caught in real-browser testing.
- Client: handleCopy calls the endpoint; `canExport = !!activeChatId`. The whole
  liveThreadRef/liveStateRef/onLiveContentChange/hasLiveContent hybrid (and the
  client chat-markdown util + test) is removed — the server is now authoritative.

Tests: flushAssistant unit (status shapes + parts parity), chat-markdown.util
unit (incl. legacy NULL-status + interrupted note + ru + normalizeLang locale
tags), controller export wiring + owner-gate, integration update/sweepStreaming.
Verified: server build + 318 ai-chat unit + 3 integration; client tsc + 157
ai-chat unit; and END-TO-END in a real browser — a chat turn persists mid-stream
and the Copy button exports the DB-sourced markdown (showing the in-progress
row), HTTP 200 after the locale fix.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
This commit is contained in:
claude code agent 227
2026-06-25 06:05:26 +03:00
parent 27c91e4a69
commit e7b719bbb8
19 changed files with 1500 additions and 1408 deletions

View File

@@ -0,0 +1,92 @@
import { ForbiddenException } from '@nestjs/common';
import { AiChatController } from './ai-chat.controller';
import type { User, Workspace } from '@docmost/db/types/entity.types';
/**
* Wiring spec for the #183 `POST /ai-chat/export` endpoint. It must: own-gate via
* the chat lookup (workspace-scoped + creator-owned), load the FULL transcript
* via findAllByChat, render server-side, and return `{ markdown }`. Exercised by
* instantiating the controller with hand-rolled mocks — no Nest graph, no DB.
*/
describe('AiChatController.export', () => {
const user = { id: 'u1' } as User;
const workspace = { id: 'ws1' } as Workspace;
function makeController(
over: {
chat?: unknown;
rows?: unknown[];
} = {},
) {
const chat =
'chat' in over
? over.chat
: { id: 'c1', creatorId: 'u1', title: 'My chat' };
const aiChatRepo = {
findById: jest.fn().mockResolvedValue(chat),
};
const aiChatMessageRepo = {
findAllByChat: jest.fn().mockResolvedValue(
over.rows ?? [
{
id: 'm1',
role: 'user',
content: 'hi',
metadata: null,
status: null,
},
{
id: 'm2',
role: 'assistant',
content: 'hello',
metadata: null,
status: 'completed',
},
],
),
};
const controller = new AiChatController(
{} as never,
aiChatRepo as never,
aiChatMessageRepo as never,
{} as never,
);
return { controller, aiChatRepo, aiChatMessageRepo };
}
it('renders the full transcript and returns { markdown }', async () => {
const { controller, aiChatMessageRepo } = makeController();
const res = await controller.export({ chatId: 'c1' }, user, workspace);
expect(aiChatMessageRepo.findAllByChat).toHaveBeenCalledWith('c1', 'ws1');
expect(res.markdown).toContain('# My chat');
expect(res.markdown).toContain('## 1. You');
expect(res.markdown).toContain('## 2. AI agent');
});
it('forbids a chat the user does not own', async () => {
const { controller } = makeController({
chat: { id: 'c1', creatorId: 'someone-else', title: 'X' },
});
await expect(
controller.export({ chatId: 'c1' }, user, workspace),
).rejects.toBeInstanceOf(ForbiddenException);
});
it('forbids a missing / foreign-workspace chat', async () => {
const { controller } = makeController({ chat: null });
await expect(
controller.export({ chatId: 'c1' }, user, workspace),
).rejects.toBeInstanceOf(ForbiddenException);
});
it('localizes labels when lang=ru is passed', async () => {
const { controller } = makeController();
const res = await controller.export(
{ chatId: 'c1', lang: 'ru' },
user,
workspace,
);
expect(res.markdown).toContain('## 1. Вы');
expect(res.markdown).toContain('## 2. ИИ-агент');
});
});

View File

@@ -20,7 +20,7 @@ import { JwtAuthGuard } from '../../common/guards/jwt-auth.guard';
import { AuthUser } from '../../common/decorators/auth-user.decorator';
import { AuthWorkspace } from '../../common/decorators/auth-workspace.decorator';
import { SkipTransform } from '../../common/decorators/skip-transform.decorator';
import { User, Workspace } from '@docmost/db/types/entity.types';
import { AiChat, User, Workspace } from '@docmost/db/types/entity.types';
import { PaginationOptions } from '@docmost/db/pagination/pagination-options';
import { AiChatRepo } from '@docmost/db/repos/ai-chat/ai-chat.repo';
import { AiChatMessageRepo } from '@docmost/db/repos/ai-chat/ai-chat-message.repo';
@@ -31,10 +31,12 @@ import { AiChatService, AiChatStreamBody } from './ai-chat.service';
import { AiTranscriptionService } from './ai-transcription.service';
import {
ChatIdDto,
ExportChatDto,
GetChatMessagesDto,
RenameChatDto,
} from './dto/ai-chat.dto';
import { describeProviderError } from '../../integrations/ai/ai-error.util';
import { buildChatMarkdown } from './chat-markdown.util';
/**
* Per-user AI chat API (§6.1). Routes are POST to match this codebase's
@@ -81,6 +83,35 @@ export class AiChatController {
);
}
/**
* Export a chat to Markdown (#183). The DB is the single source of truth: the
* whole transcript is loaded (oldest -> newest) and rendered server-side. Now
* that the assistant row is persisted upfront and per step, an interrupted
* turn is included up to its last finished step. Workspace-scoped and owner-
* gated via assertOwnedChat (same as the other read endpoints). Returns
* `{ markdown }`. `lang` localizes the few fixed labels (default English).
*/
@HttpCode(HttpStatus.OK)
@Post('export')
async export(
@Body() dto: ExportChatDto,
@AuthUser() user: User,
@AuthWorkspace() workspace: Workspace,
): Promise<{ markdown: string }> {
const chat = await this.assertOwnedChat(dto.chatId, user, workspace);
const rows = await this.aiChatMessageRepo.findAllByChat(
dto.chatId,
workspace.id,
);
const markdown = buildChatMarkdown({
title: chat.title ?? null,
chatId: dto.chatId,
rows,
lang: dto.lang ?? 'en',
});
return { markdown };
}
/** Rename a chat. */
@HttpCode(HttpStatus.OK)
@Post('rename')
@@ -90,7 +121,11 @@ export class AiChatController {
@AuthWorkspace() workspace: Workspace,
) {
await this.assertOwnedChat(dto.chatId, user, workspace);
await this.aiChatRepo.update(dto.chatId, { title: dto.title }, workspace.id);
await this.aiChatRepo.update(
dto.chatId,
{ title: dto.title },
workspace.id,
);
return { success: true };
}
@@ -145,7 +180,10 @@ export class AiChatController {
// Resolve the agent role for this turn BEFORE hijack: existing chats read it
// from ai_chats.role_id (authoritative), a new chat from body.roleId. The
// role drives both the persona and the optional model override below.
const role = await this.aiChatService.resolveRoleForRequest(workspace, body);
const role = await this.aiChatService.resolveRoleForRequest(
workspace,
body,
);
// Resolve the model (applying the role's optional override) BEFORE hijack so
// an unconfigured provider — including a role pointing at an unconfigured
@@ -232,7 +270,9 @@ export class AiChatController {
let file = null;
try {
// Whisper hard-caps uploads at 25MB; allow a single file.
file = await req.file({ limits: { fileSize: 25 * 1024 * 1024, files: 1 } });
file = await req.file({
limits: { fileSize: 25 * 1024 * 1024, files: 1 },
});
} catch (err: any) {
if (err?.statusCode === 413) {
throw new BadRequestException('Audio file too large (max 25MB)');
@@ -283,11 +323,12 @@ export class AiChatController {
chatId: string,
user: User,
workspace: Workspace,
): Promise<void> {
): Promise<AiChat> {
const chat = await this.aiChatRepo.findById(chatId, workspace.id);
if (!chat || chat.creatorId !== user.id) {
throw new ForbiddenException();
}
return chat;
}
}

View File

@@ -5,6 +5,7 @@ import {
rowToUiMessage,
prepareAgentStep,
buildPartialAssistantRecord,
flushAssistant,
chatStreamMetadata,
accumulateStepUsage,
MAX_AGENT_STEPS,
@@ -94,8 +95,12 @@ describe('assistantParts', () => {
const steps = [
{
text: '',
toolCalls: [{ toolCallId: 'c1', toolName: 'getPage', input: { id: 'p1' } }],
toolResults: [{ toolCallId: 'c1', toolName: 'getPage', output: { title: 'T' } }],
toolCalls: [
{ toolCallId: 'c1', toolName: 'getPage', input: { id: 'p1' } },
],
toolResults: [
{ toolCallId: 'c1', toolName: 'getPage', output: { title: 'T' } },
],
},
];
const parts = assistantParts(steps, '') as AnyPart[];
@@ -109,7 +114,9 @@ describe('assistantParts', () => {
const steps = [
{
text: '',
toolCalls: [{ toolCallId: 'c9', toolName: 'insertNode', input: { node: {} } }],
toolCalls: [
{ toolCallId: 'c9', toolName: 'insertNode', input: { node: {} } },
],
toolResults: [],
},
];
@@ -136,7 +143,8 @@ describe('assistantParts', () => {
];
const parts = assistantParts(steps, '') as AnyPart[];
const toolParts = parts.filter(
(p) => typeof p.type === 'string' && (p.type as string).startsWith('tool-'),
(p) =>
typeof p.type === 'string' && (p.type as string).startsWith('tool-'),
);
expect(toolParts).toHaveLength(0);
});
@@ -246,16 +254,30 @@ describe('buildPartialAssistantRecord', () => {
type AnyPart = Record<string, unknown>;
it('records an empty turn with the error text (preserves old behavior)', () => {
const rec = buildPartialAssistantRecord([], '', 'error', '401: Unauthorized');
const rec = buildPartialAssistantRecord(
[],
'',
'error',
'401: Unauthorized',
);
expect(rec).toEqual({
text: '',
toolCalls: null,
metadata: { finishReason: 'error', parts: [], error: '401: Unauthorized' },
metadata: {
finishReason: 'error',
parts: [],
error: '401: Unauthorized',
},
});
});
it('persists in-progress text (no finished steps) as the partial answer', () => {
const rec = buildPartialAssistantRecord([], 'partial answer', 'error', 'boom');
const rec = buildPartialAssistantRecord(
[],
'partial answer',
'error',
'boom',
);
expect(rec.text).toBe('partial answer');
expect(rec.metadata.parts).toEqual([
{ type: 'text', text: 'partial answer' },
@@ -275,7 +297,12 @@ describe('buildPartialAssistantRecord', () => {
],
},
];
const rec = buildPartialAssistantRecord(steps, ' and then', 'error', 'boom');
const rec = buildPartialAssistantRecord(
steps,
' and then',
'error',
'boom',
);
const parts = rec.metadata.parts as AnyPart[];
// The finished step's text part is present.
expect(parts).toContainEqual({ type: 'text', text: 'looked it up' });
@@ -284,7 +311,10 @@ describe('buildPartialAssistantRecord', () => {
expect(toolPart).toBeDefined();
expect(toolPart!.state).toBe('output-available');
// The in-progress text is appended LAST so the parts match the stream order.
expect(parts[parts.length - 1]).toEqual({ type: 'text', text: ' and then' });
expect(parts[parts.length - 1]).toEqual({
type: 'text',
text: ' and then',
});
expect(rec.text).toBe('looked it up and then');
expect(rec.toolCalls).not.toBeNull();
expect(rec.metadata.error).toBe('boom');
@@ -298,6 +328,107 @@ describe('buildPartialAssistantRecord', () => {
});
});
/**
* flushAssistant (#183): the PURE row builder behind the step-granular durable
* write path. It runs identically for the upfront insert (empty steps,
* 'streaming'), every per-step update, and the terminal finalize — so a future
* background worker can call the same function. These tests pin the four status
* shapes and, critically, that `metadata.parts` stays IDENTICAL to the old
* buildPartialAssistantRecord / assistantParts output (rowToUiMessage/findRecent
* depend on it).
*/
describe('flushAssistant', () => {
type AnyPart = Record<string, unknown>;
const toolStep = {
text: 'looked it up',
toolCalls: [{ toolCallId: 'c1', toolName: 'getPage', input: { id: 'p1' } }],
toolResults: [
{ toolCallId: 'c1', toolName: 'getPage', output: { title: 'T' } },
],
};
it('upfront seed: empty streaming row (no content, no toolCalls, empty parts)', () => {
const f = flushAssistant([], '', 'streaming');
expect(f.status).toBe('streaming');
expect(f.content).toBe('');
expect(f.toolCalls).toBeNull();
expect(f.metadata.parts).toEqual([]);
// No finishReason while streaming (it is not a terminal state).
expect('finishReason' in f.metadata).toBe(false);
});
it('streaming update folds in finished steps but keeps status streaming', () => {
const f = flushAssistant([toolStep], '', 'streaming');
expect(f.status).toBe('streaming');
expect(f.content).toBe('looked it up');
const parts = f.metadata.parts as AnyPart[];
expect(parts).toContainEqual({ type: 'text', text: 'looked it up' });
const toolPart = parts.find((p) => p.type === 'tool-getPage');
expect(toolPart!.state).toBe('output-available');
expect(f.toolCalls).not.toBeNull();
});
it('completed: attaches finishReason + normalized usage + contextTokens', () => {
const f = flushAssistant([toolStep], '', 'completed', {
finishReason: 'stop',
usage: { inputTokens: 10, outputTokens: 5, totalTokens: 15 },
contextTokens: 15,
});
expect(f.status).toBe('completed');
expect(f.metadata.finishReason).toBe('stop');
expect(f.metadata.usage).toEqual({
inputTokens: 10,
outputTokens: 5,
totalTokens: 15,
reasoningTokens: undefined,
});
expect(f.metadata.contextTokens).toBe(15);
});
it('error: records the error and a derived finishReason', () => {
const f = flushAssistant([], 'partial answer', 'error', { error: 'boom' });
expect(f.status).toBe('error');
expect(f.content).toBe('partial answer');
expect(f.metadata.error).toBe('boom');
// Derives finishReason from the terminal status when none is supplied.
expect(f.metadata.finishReason).toBe('error');
expect(f.metadata.parts).toEqual([
{ type: 'text', text: 'partial answer' },
]);
});
it('aborted: in-progress text appended last, no error key', () => {
const f = flushAssistant([toolStep], ' and then', 'aborted');
expect(f.status).toBe('aborted');
expect(f.metadata.finishReason).toBe('aborted');
expect('error' in f.metadata).toBe(false);
expect(f.content).toBe('looked it up and then');
const parts = f.metadata.parts as AnyPart[];
expect(parts[parts.length - 1]).toEqual({
type: 'text',
text: ' and then',
});
});
it('metadata.parts parity with buildPartialAssistantRecord (error path)', () => {
const flushed = flushAssistant([toolStep], ' and then', 'error', {
error: 'boom',
});
const legacy = buildPartialAssistantRecord(
[toolStep],
' and then',
'error',
'boom',
);
// The whole metadata block (parts + finishReason + error) must match the
// legacy partial-record shape so rebuilt history is unchanged.
expect(flushed.metadata).toEqual(legacy.metadata);
expect(flushed.content).toBe(legacy.text);
expect(flushed.toolCalls).toEqual(legacy.toolCalls);
});
});
/**
* chatStreamMetadata: attach metadata to the streamed assistant UI message per
* part type — `chatId` on `start` (so the client adopts the real created chat id
@@ -319,10 +450,20 @@ describe('chatStreamMetadata', () => {
chatStreamMetadata(
{ type: 'finish-step', usage: { outputTokens: 100 } },
'chat-1',
{ inputTokens: 500, outputTokens: 220, totalTokens: 720, reasoningTokens: 30 },
{
inputTokens: 500,
outputTokens: 220,
totalTokens: 720,
reasoningTokens: 30,
},
),
).toEqual({
usage: { inputTokens: 500, outputTokens: 220, totalTokens: 720, reasoningTokens: 30 },
usage: {
inputTokens: 500,
outputTokens: 220,
totalTokens: 720,
reasoningTokens: 30,
},
});
});
@@ -394,8 +535,18 @@ describe('accumulateStepUsage', () => {
it('sums every field across two steps', () => {
expect(
accumulateStepUsage(
{ inputTokens: 500, outputTokens: 100, totalTokens: 600, reasoningTokens: 30 },
{ inputTokens: 520, outputTokens: 80, totalTokens: 600, reasoningTokens: 10 },
{
inputTokens: 500,
outputTokens: 100,
totalTokens: 600,
reasoningTokens: 30,
},
{
inputTokens: 520,
outputTokens: 80,
totalTokens: 600,
reasoningTokens: 10,
},
),
).toEqual({
inputTokens: 1020,

View File

@@ -1,4 +1,9 @@
import { ForbiddenException, Injectable, Logger } from '@nestjs/common';
import {
ForbiddenException,
Injectable,
Logger,
OnModuleInit,
} from '@nestjs/common';
import { FastifyReply } from 'fastify';
import {
streamText,
@@ -60,7 +65,10 @@ export function prepareAgentStep(
system: string,
): { toolChoice: 'none'; system: string } | undefined {
if (stepNumber >= MAX_AGENT_STEPS - 1) {
return { toolChoice: 'none', system: `${system}\n\n${FINAL_STEP_INSTRUCTION}` };
return {
toolChoice: 'none',
system: `${system}\n\n${FINAL_STEP_INSTRUCTION}`,
};
}
return undefined;
}
@@ -121,7 +129,7 @@ export interface AiChatStreamArgs {
* can be rebuilt for `convertToModelMessages`.
*/
@Injectable()
export class AiChatService {
export class AiChatService implements OnModuleInit {
private readonly logger = new Logger(AiChatService.name);
constructor(
@@ -136,6 +144,32 @@ export class AiChatService {
private readonly pageAccess: PageAccessService,
) {}
/**
* Crash-recovery sweep on server start (#183): any assistant row left in the
* 'streaming' state is the relic of a turn whose process died before it
* reached a terminal status. Flip those to 'aborted' so history/export show
* them settled (with whatever finished steps were already persisted) instead
* of perpetually "streaming". Best-effort: a sweep failure is logged but must
* never block server startup.
*/
async onModuleInit(): Promise<void> {
try {
const swept = await this.aiChatMessageRepo.sweepStreaming();
if (swept > 0) {
this.logger.log(
`Startup sweep: marked ${swept} dangling 'streaming' assistant ` +
`message(s) as 'aborted'.`,
);
}
} catch (err) {
this.logger.warn(
`Startup sweep of dangling 'streaming' messages failed: ${
err instanceof Error ? err.message : 'unknown error'
}`,
);
}
}
/**
* Resolve the agent role that applies to this stream request, scoped to the
* workspace and soft-delete aware. For an EXISTING chat the role is read from
@@ -259,9 +293,7 @@ export class AiChatService {
content: incomingText,
// jsonb column: UIMessage parts are JSON-serializable at runtime but not
// structurally `JsonValue`, so cast through unknown.
metadata: (incoming?.parts
? { parts: incoming.parts }
: null) as never,
metadata: (incoming?.parts ? { parts: incoming.parts } : null) as never,
});
// Rebuild the conversation from persisted history (not the client payload),
@@ -347,31 +379,6 @@ export class AiChatService {
);
};
// Persist the assistant message. Used by onFinish (full result) and the
// abort/error paths (partial result). Guarded so we persist at most once.
let persisted = false;
const persistAssistant = async (data: {
text: string;
toolCalls: unknown;
metadata: Record<string, unknown>;
}): Promise<void> => {
if (persisted) return;
persisted = true;
try {
await this.aiChatMessageRepo.insert({
chatId,
workspaceId: workspace.id,
userId: user.id,
role: 'assistant',
content: data.text ?? '',
toolCalls: (data.toolCalls ?? null) as never,
metadata: data.metadata as never,
});
} catch (err) {
this.logger.error('Failed to persist assistant message', err as Error);
}
};
// Accumulate the turn's streamed output so a provider error / disconnect can
// persist the PARTIAL answer the user already saw — the SDK's onError/onAbort
// callbacks don't hand us the in-progress text. `capturedSteps` holds finished
@@ -380,6 +387,94 @@ export class AiChatService {
const capturedSteps: StepLike[] = [];
let inProgressText = '';
// Step-granular durability (#183): create the assistant row UPFRONT in the
// 'streaming' state (before any token), then UPDATE it as each step finishes
// and finalize it once on the terminal callback. If the process dies
// mid-turn the row survives with every finished step already persisted; the
// startup sweep (sweepStreaming) later flips a dangling 'streaming' row to
// 'aborted'. The DB is now the single source of truth for the turn — the
// socket is never required for the write path. A failed upfront insert is
// logged and leaves assistantId undefined; the per-step/terminal updates then
// no-op (guarded below) so the turn still streams to the user.
let assistantId: string | undefined;
try {
const seed = flushAssistant([], '', 'streaming');
const seeded = await this.aiChatMessageRepo.insert({
chatId,
workspaceId: workspace.id,
userId: user.id,
role: 'assistant',
content: seed.content,
// jsonb columns: cast through never (same as the user insert above).
toolCalls: (seed.toolCalls ?? null) as never,
metadata: seed.metadata as never,
status: seed.status,
});
assistantId = seeded?.id;
} catch (err) {
this.logger.error('Failed to insert upfront assistant row', err as Error);
}
// Per-step (non-terminal) update: persist the finished steps the moment a
// step ends. Tolerant — a failed update is logged and swallowed so it never
// throws into the stream. Keeps status 'streaming'.
const updateStreaming = async (): Promise<void> => {
if (!assistantId) return;
try {
await this.aiChatMessageRepo.update(
assistantId,
workspace.id,
flushAssistant(capturedSteps, '', 'streaming'),
);
} catch (err) {
this.logger.warn(
`Failed to update streaming assistant row: ${
err instanceof Error ? err.message : 'unknown error'
}`,
);
}
};
// Terminal finalize: write the completed/error/aborted row exactly once
// across the (mutually-exclusive, at-most-once) onFinish/onError/onAbort
// callbacks — mirroring the pre-#183 persist-at-most-once guard for the
// TERMINAL status (the row may be updated many times with 'streaming' before
// this fires once).
let finalized = false;
const finalizeAssistant = async (
flushed: AssistantFlush,
): Promise<void> => {
if (finalized) return;
finalized = true;
if (!assistantId) {
// The upfront insert failed: fall back to inserting the terminal row so
// the turn is not lost entirely.
try {
await this.aiChatMessageRepo.insert({
chatId,
workspaceId: workspace.id,
userId: user.id,
role: 'assistant',
content: flushed.content,
toolCalls: (flushed.toolCalls ?? null) as never,
metadata: flushed.metadata as never,
status: flushed.status,
});
} catch (err) {
this.logger.error(
'Failed to persist terminal assistant message',
err as Error,
);
}
return;
}
try {
await this.aiChatMessageRepo.update(assistantId, workspace.id, flushed);
} catch (err) {
this.logger.error('Failed to finalize assistant message', err as Error);
}
};
// DIAGNOSTIC (Safari stream-drop investigation) — temporary. Measure
// first-chunk latency, the model-silent gap right before a disconnect, and
// how many SSE heartbeats were written, so a Safari drop can be classified
@@ -395,144 +490,141 @@ export class AiChatService {
let result: ReturnType<typeof streamText>;
try {
result = streamText({
model,
system,
messages,
tools,
// No maxOutputTokens cap on the agent: tool-call arguments (e.g. a full
// page body for the write tools) are emitted as OUTPUT tokens, so a fixed
// cap would truncate complex tool calls mid-argument. Let the model use its
// natural per-step budget. (Cost/credit limits are an account concern, not
// something to enforce by silently breaking the agent.)
stopWhen: stepCountIs(MAX_AGENT_STEPS),
// Forced finalization: reserve the LAST allowed step for a text-only
// answer. Without this, a turn that spends all its steps on tool calls
// ends with no assistant text (an empty turn). prepareAgentStep forbids
// further tool calls and appends a synthesis instruction on that step,
// concatenated onto the original `system` so the persona is preserved.
prepareStep: ({ stepNumber }) => prepareAgentStep(stepNumber, system),
abortSignal: signal,
onChunk: ({ chunk }) => {
// DIAGNOSTIC (Safari stream-drop investigation) — temporary. Any model
// output chunk means the stream is actively emitting bytes; track first
// + most-recent activity timestamps.
const now = Date.now();
firstModelChunkAt ??= now;
lastModelChunkAt = now;
// 'text-delta' is the assistant's prose; tool-call args are separate chunk
// types — so this mirrors exactly what streams to the client.
if (chunk.type === 'text-delta') inProgressText += chunk.text;
},
onStepFinish: (step) => {
// The finished step's full text is now in `step.text`; fold it in and reset
// the in-progress accumulator for the next step.
capturedSteps.push(step as StepLike);
inProgressText = '';
},
onFinish: async ({ text, finishReason, totalUsage, usage, steps }) => {
// DIAGNOSTIC (Safari stream-drop investigation) — temporary: success
// baseline for Safari comparison.
const diagNow = Date.now();
this.logger.log(
`AI chat stream DIAGNOSTIC (finish): elapsed=${diagNow - streamStartedAt}ms ` +
`firstChunkLatency=${firstModelChunkAt ? firstModelChunkAt - streamStartedAt : 'none'}ms ` +
`heartbeatsSent=${heartbeatsSent} steps=${steps.length}`,
);
await persistAssistant({
text,
toolCalls: serializeSteps(steps),
metadata: {
finishReason,
// Persist the turn's cumulative usage WITH reasoning tokens resolved
// from either the new `outputTokenDetails` or the deprecated top-level
// field, so reopened history / the Markdown export show the thinking
// token cost too.
usage: normalizeStreamUsage(totalUsage as StreamUsage) ?? totalUsage,
// Final-step usage = the context actually fed to the model on the last LLM
// call (full history + tool results) plus the answer it just generated.
// input+output of the FINAL step ≈ the conversation's CURRENT context size,
// distinct from totalUsage which sums every step (cumulative tokens spent).
contextTokens:
(usage?.inputTokens ?? 0) + (usage?.outputTokens ?? 0) || undefined,
// Persist the FULL set of UIMessage parts for the turn (text +
// tool-call/result), so the rebuilt history replays prior tool
// context to the model on later turns.
parts: assistantParts(steps, text),
},
});
// Lifecycle: release the external MCP clients leased for this turn.
await closeExternalClients();
// Generate the chat title for a freshly created chat AFTER the stream's
// provider call has completed — NOT concurrently with it. The z.ai coding
// endpoint stalls one of two concurrent requests to the same plan, which
// black-holed the chat stream (~300s headers timeout) when title
// generation raced it. Running it here (solo, fire-and-forget) avoids the
// race; never block the turn on it, swallow any error.
if (isNewChat && incomingText) {
void this.generateTitle(chatId, workspace.id, incomingText).catch(
(err) => {
this.logger.warn(
`Title generation failed: ${(err as Error)?.message ?? err}`,
);
},
model,
system,
messages,
tools,
// No maxOutputTokens cap on the agent: tool-call arguments (e.g. a full
// page body for the write tools) are emitted as OUTPUT tokens, so a fixed
// cap would truncate complex tool calls mid-argument. Let the model use its
// natural per-step budget. (Cost/credit limits are an account concern, not
// something to enforce by silently breaking the agent.)
stopWhen: stepCountIs(MAX_AGENT_STEPS),
// Forced finalization: reserve the LAST allowed step for a text-only
// answer. Without this, a turn that spends all its steps on tool calls
// ends with no assistant text (an empty turn). prepareAgentStep forbids
// further tool calls and appends a synthesis instruction on that step,
// concatenated onto the original `system` so the persona is preserved.
prepareStep: ({ stepNumber }) => prepareAgentStep(stepNumber, system),
abortSignal: signal,
onChunk: ({ chunk }) => {
// DIAGNOSTIC (Safari stream-drop investigation) — temporary. Any model
// output chunk means the stream is actively emitting bytes; track first
// + most-recent activity timestamps.
const now = Date.now();
firstModelChunkAt ??= now;
lastModelChunkAt = now;
// 'text-delta' is the assistant's prose; tool-call args are separate chunk
// types — so this mirrors exactly what streams to the client.
if (chunk.type === 'text-delta') inProgressText += chunk.text;
},
onStepFinish: (step) => {
// The finished step's full text is now in `step.text`; fold it in and reset
// the in-progress accumulator for the next step.
capturedSteps.push(step as StepLike);
inProgressText = '';
// Step-granular durability (#183): persist this finished step (its text +
// tool calls + tool RESULTS) the moment it ends, so a process death after
// this point still recovers the step. Fire-and-forget but error-tolerant
// (updateStreaming logs + swallows) — never throw into the stream.
void updateStreaming();
},
onFinish: async ({ text, finishReason, totalUsage, usage, steps }) => {
// DIAGNOSTIC (Safari stream-drop investigation) — temporary: success
// baseline for Safari comparison.
const diagNow = Date.now();
this.logger.log(
`AI chat stream DIAGNOSTIC (finish): elapsed=${diagNow - streamStartedAt}ms ` +
`firstChunkLatency=${firstModelChunkAt ? firstModelChunkAt - streamStartedAt : 'none'}ms ` +
`heartbeatsSent=${heartbeatsSent} steps=${steps.length}`,
);
}
},
onError: async ({ error }) => {
// NestJS Logger.error(message, stack?, context?): pass the real message
// (with statusCode when present) + the stack string, not the Error
// object, so the actual provider cause is clearly logged. Reuse the
// shared formatter so provider error formatting stays unified.
const e = error as { stack?: string };
const errorText = describeProviderError(error, String(error));
this.logger.error(`AI chat stream error: ${errorText}`, e?.stack);
// DIAGNOSTIC (Safari stream-drop investigation) — temporary: timing of
// an error-terminated stream.
const diagNow = Date.now();
this.logger.warn(
`AI chat stream DIAGNOSTIC (error): elapsed=${diagNow - streamStartedAt}ms ` +
`firstChunkLatency=${firstModelChunkAt ? firstModelChunkAt - streamStartedAt : 'none'}ms ` +
`silentGapBeforeDrop=${diagNow - lastModelChunkAt}ms heartbeatsSent=${heartbeatsSent}`,
);
// Persist the PARTIAL answer streamed before the failure (text + any
// finished tool steps) WITH the error in metadata, so the turn shows what
// the user already saw plus the cause — not just a bare error.
await persistAssistant(
buildPartialAssistantRecord(
capturedSteps,
inProgressText,
'error',
errorText,
),
);
await closeExternalClients();
},
onAbort: async ({ steps }) => {
const partialChars =
capturedSteps.reduce((n, s) => n + (s.text?.length ?? 0), 0) +
inProgressText.length;
// Unlike onError/onFinish, this terminal path otherwise writes nothing, so
// an aborted turn (client disconnect / proxy drop / stop()) would be
// invisible in the logs. Log it (warn) so the abort is traceable.
this.logger.warn(
`AI chat stream aborted (chat ${chatId}) after ${steps.length} ` +
`step(s), ${partialChars} chars partial text; persisting partial turn.`,
);
// DIAGNOSTIC (Safari stream-drop investigation) — temporary: THE key
// line — classifies the Safari drop.
const diagNow = Date.now();
this.logger.warn(
`AI chat stream DIAGNOSTIC (abort/disconnect): elapsed=${diagNow - streamStartedAt}ms ` +
`firstChunkLatency=${firstModelChunkAt ? firstModelChunkAt - streamStartedAt : 'none'}ms ` +
`silentGapBeforeDrop=${diagNow - lastModelChunkAt}ms heartbeatsSent=${heartbeatsSent} ` +
`steps=${steps.length}`,
);
await persistAssistant(
buildPartialAssistantRecord(capturedSteps, inProgressText, 'aborted'),
);
await closeExternalClients();
},
// Finalize the assistant row (#183): the upfront 'streaming' row is
// UPDATEd to 'completed' with the turn's final text, cumulative usage and
// full UIMessage parts. We pass the SDK `steps` (which carry the final
// step's text) as the captured steps so metadata.parts matches the
// pre-#183 onFinish record exactly; `inProgressText` is '' here (the last
// step already finished). Final-step usage (usage.input+output) ≈ the
// conversation's CURRENT context size, distinct from totalUsage.
await finalizeAssistant(
flushAssistant(steps as StepLike[], '', 'completed', {
finishReason: finishReason as string,
usage: totalUsage as StreamUsage,
contextTokens:
(usage?.inputTokens ?? 0) + (usage?.outputTokens ?? 0) ||
undefined,
}),
);
// Lifecycle: release the external MCP clients leased for this turn.
await closeExternalClients();
// Generate the chat title for a freshly created chat AFTER the stream's
// provider call has completed — NOT concurrently with it. The z.ai coding
// endpoint stalls one of two concurrent requests to the same plan, which
// black-holed the chat stream (~300s headers timeout) when title
// generation raced it. Running it here (solo, fire-and-forget) avoids the
// race; never block the turn on it, swallow any error.
if (isNewChat && incomingText) {
void this.generateTitle(chatId, workspace.id, incomingText).catch(
(err) => {
this.logger.warn(
`Title generation failed: ${(err as Error)?.message ?? err}`,
);
},
);
}
},
onError: async ({ error }) => {
// NestJS Logger.error(message, stack?, context?): pass the real message
// (with statusCode when present) + the stack string, not the Error
// object, so the actual provider cause is clearly logged. Reuse the
// shared formatter so provider error formatting stays unified.
const e = error as { stack?: string };
const errorText = describeProviderError(error, String(error));
this.logger.error(`AI chat stream error: ${errorText}`, e?.stack);
// DIAGNOSTIC (Safari stream-drop investigation) — temporary: timing of
// an error-terminated stream.
const diagNow = Date.now();
this.logger.warn(
`AI chat stream DIAGNOSTIC (error): elapsed=${diagNow - streamStartedAt}ms ` +
`firstChunkLatency=${firstModelChunkAt ? firstModelChunkAt - streamStartedAt : 'none'}ms ` +
`silentGapBeforeDrop=${diagNow - lastModelChunkAt}ms heartbeatsSent=${heartbeatsSent}`,
);
// Finalize the PARTIAL answer streamed before the failure (text + any
// finished tool steps) WITH the error in metadata, so the turn shows what
// the user already saw plus the cause — not just a bare error. Status
// 'error' (#183).
await finalizeAssistant(
flushAssistant(capturedSteps, inProgressText, 'error', {
error: errorText,
}),
);
await closeExternalClients();
},
onAbort: async ({ steps }) => {
const partialChars =
capturedSteps.reduce((n, s) => n + (s.text?.length ?? 0), 0) +
inProgressText.length;
// Unlike onError/onFinish, this terminal path otherwise writes nothing, so
// an aborted turn (client disconnect / proxy drop / stop()) would be
// invisible in the logs. Log it (warn) so the abort is traceable.
this.logger.warn(
`AI chat stream aborted (chat ${chatId}) after ${steps.length} ` +
`step(s), ${partialChars} chars partial text; persisting partial turn.`,
);
// DIAGNOSTIC (Safari stream-drop investigation) — temporary: THE key
// line — classifies the Safari drop.
const diagNow = Date.now();
this.logger.warn(
`AI chat stream DIAGNOSTIC (abort/disconnect): elapsed=${diagNow - streamStartedAt}ms ` +
`firstChunkLatency=${firstModelChunkAt ? firstModelChunkAt - streamStartedAt : 'none'}ms ` +
`silentGapBeforeDrop=${diagNow - lastModelChunkAt}ms heartbeatsSent=${heartbeatsSent} ` +
`steps=${steps.length}`,
);
await finalizeAssistant(
flushAssistant(capturedSteps, inProgressText, 'aborted'),
);
await closeExternalClients();
},
});
// Drain the stream independently of the client socket so the turn always
@@ -652,7 +744,10 @@ export class AiChatService {
'punctuation at the end.',
prompt: firstMessage.slice(0, 2000),
});
const title = text.trim().replace(/^["']|["']$/g, '').slice(0, 120);
const title = text
.trim()
.replace(/^["']|["']$/g, '')
.slice(0, 120);
if (title) {
await this.aiChatRepo.update(chatId, { title }, workspaceId);
}
@@ -974,6 +1069,82 @@ export function rowToUiMessage(row: AiChatMessage): Omit<UIMessage, 'id'> & {
return { id: row.id, role, parts: parts as UIMessage['parts'] };
}
/**
* The persisted-row patch shape produced by {@link flushAssistant}. It is the
* SAME shape the assistant repo insert/update consume (content + toolCalls +
* metadata) plus the lifecycle `status` column added in #183.
*/
export interface AssistantFlush {
content: string;
toolCalls: unknown;
metadata: Record<string, unknown>;
status: 'streaming' | 'completed' | 'error' | 'aborted';
}
/**
* PURE assistant-row builder (#183 step-granular durability). Given the turn's
* accumulated steps + the in-progress (not-yet-finished) text + the lifecycle
* status, it returns the row patch to persist. The SAME path runs for the
* upfront insert (empty steps, status 'streaming'), every per-step update, and
* the terminal finalize (completed/error/aborted) — and a future background
* worker can call it identically, so it must stay a pure function of its inputs
* (NO `this`, no IO).
*
* `metadata.parts` is built by the EXACT same logic the old
* buildPartialAssistantRecord used (assistantParts over finished steps, then the
* in-progress text appended as a trailing text part), so rowToUiMessage /
* findRecent keep replaying the turn unchanged. `metadata.finishReason`,
* `metadata.error`, `metadata.usage` and `metadata.contextTokens` are attached
* only when provided/relevant, matching the pre-#183 onFinish/onError records.
*/
export function flushAssistant(
capturedSteps: ReadonlyArray<StepLike> | undefined,
inProgressText: string,
status: 'streaming' | 'completed' | 'error' | 'aborted',
extra?: {
finishReason?: string;
usage?: ChatStreamUsage | StreamUsage | undefined;
contextTokens?: number;
error?: string;
},
): AssistantFlush {
const finished = capturedSteps ?? [];
const stepsText = finished.map((s) => s.text ?? '').join('');
const trailing = inProgressText ?? '';
// assistantParts emits text parts only for FINISHED steps; append the
// in-progress step's text (the partial answer cut off by an error/abort, or
// simply not yet flushed mid-stream) as the last text part so the persisted
// parts match what streamed to the client.
const parts = assistantParts(finished, '') as unknown as Array<
Record<string, unknown>
>;
if (trailing) parts.push({ type: 'text', text: trailing });
const metadata: Record<string, unknown> = {
parts: parts as unknown as UIMessage['parts'],
};
// finishReason: prefer an explicit one; else derive a sensible value from the
// terminal status (so onError/onAbort records keep their historical reason).
if (extra?.finishReason) {
metadata.finishReason = extra.finishReason;
} else if (status === 'error' || status === 'aborted') {
metadata.finishReason = status;
}
if (extra?.usage !== undefined) {
metadata.usage =
normalizeStreamUsage(extra.usage as StreamUsage) ?? extra.usage;
}
if (extra?.contextTokens) metadata.contextTokens = extra.contextTokens;
if (extra?.error) metadata.error = extra.error;
return {
content: stepsText + trailing,
toolCalls: serializeSteps(finished),
metadata,
status,
};
}
/**
* Build the assistant-message record persisted on a partial/failed turn (the
* streamText onError / onAbort paths). Captures the partial answer the user
@@ -982,6 +1153,9 @@ export function rowToUiMessage(row: AiChatMessage): Omit<UIMessage, 'id'> & {
* it is recorded in metadata.error so the cause shows in history; an aborted
* turn passes none. Pure, so the partial-recording shape is unit-testable
* without seaming streamText.
*
* Thin wrapper over {@link flushAssistant} (retained for the existing unit
* tests and its historical `{ text, toolCalls, metadata }` shape).
*/
export function buildPartialAssistantRecord(
steps: ReadonlyArray<StepLike> | undefined,
@@ -989,24 +1163,13 @@ export function buildPartialAssistantRecord(
finishReason: 'error' | 'aborted',
errorText?: string,
): { text: string; toolCalls: unknown; metadata: Record<string, unknown> } {
const finished = steps ?? [];
const stepsText = finished.map((s) => s.text ?? '').join('');
const trailing = inProgressText ?? '';
// assistantParts emits text parts only for FINISHED steps; append the
// in-progress step's text (the answer cut off by the error) as the last text
// part so the persisted parts match what streamed to the client.
const parts = assistantParts(finished, '') as unknown as Array<
Record<string, unknown>
>;
if (trailing) parts.push({ type: 'text', text: trailing });
const flushed = flushAssistant(steps, inProgressText, finishReason, {
error: errorText,
});
return {
text: stepsText + trailing,
toolCalls: serializeSteps(finished),
metadata: {
finishReason,
parts: parts as unknown as UIMessage['parts'],
...(errorText ? { error: errorText } : {}),
},
text: flushed.content,
toolCalls: flushed.toolCalls,
metadata: flushed.metadata,
};
}

View File

@@ -0,0 +1,221 @@
import { buildChatMarkdown, normalizeLang } from './chat-markdown.util';
import type { AiChatMessage } from '@docmost/db/types/entity.types';
/**
* normalizeLang: the client sends `i18n.language` — a FULL locale tag like
* 'en-US' / 'ru-RU', NOT a bare 'en'/'ru'. A `@IsIn(['en','ru'])` DTO rejected
* that with a 400 (caught in real-browser testing); the export now accepts any
* string and normalizes here. Guards that regression.
*/
describe('normalizeLang', () => {
it("maps any 'ru…' locale tag to ru", () => {
expect(normalizeLang('ru')).toBe('ru');
expect(normalizeLang('ru-RU')).toBe('ru');
expect(normalizeLang('RU-ru')).toBe('ru');
});
it('maps everything else (incl. region-qualified English) to en', () => {
expect(normalizeLang('en')).toBe('en');
expect(normalizeLang('en-US')).toBe('en');
expect(normalizeLang('fr-FR')).toBe('en');
expect(normalizeLang(undefined)).toBe('en');
expect(normalizeLang('')).toBe('en');
});
});
/**
* Unit tests for the SERVER Markdown export (#183). Mirrors the coverage of the
* (now-removed) client chat-markdown tests: heading/metadata, role labels, text
* + tool blocks, token footers, the interrupted-turn note, and NULL-status
* (legacy) rows. The export embeds a live `new Date().toISOString()` timestamp;
* we never assert it, only the deterministic structure.
*/
function row(partial: Partial<AiChatMessage>): AiChatMessage {
return {
id: partial.id ?? 'id',
chatId: partial.chatId ?? 'chat-1',
workspaceId: partial.workspaceId ?? 'ws-1',
userId: partial.userId ?? null,
role: partial.role ?? 'user',
content: partial.content ?? null,
toolCalls: partial.toolCalls ?? null,
metadata: partial.metadata ?? null,
status: partial.status ?? null,
createdAt: partial.createdAt ?? ('2026-06-21T00:00:00.000Z' as never),
updatedAt: partial.updatedAt ?? ('2026-06-21T00:00:00.000Z' as never),
deletedAt: partial.deletedAt ?? null,
} as AiChatMessage;
}
describe('buildChatMarkdown (server) — structure', () => {
it('emits the title heading, chat id and message count', () => {
const md = buildChatMarkdown({
title: 'My chat',
chatId: 'chat-123',
rows: [],
});
expect(md).toContain('# My chat');
expect(md).toContain('- Chat ID: `chat-123`');
expect(md).toContain('- Messages: 0');
});
it('falls back to "Untitled chat" with no title (en)', () => {
const md = buildChatMarkdown({ title: null, chatId: 'c', rows: [] });
expect(md).toContain('# Untitled chat');
});
it('localizes fixed labels with lang=ru (structure stays English)', () => {
const md = buildChatMarkdown({
title: null,
chatId: 'c',
lang: 'ru',
rows: [row({ role: 'assistant', content: 'hi' })],
});
expect(md).toContain('# Без названия');
expect(md).toContain('## 1. ИИ-агент');
// Structural words remain English.
expect(md).toContain('- Chat ID:');
});
it('numbers messages and labels roles (You / AI agent)', () => {
const md = buildChatMarkdown({
title: 'T',
chatId: 'c',
rows: [
row({ role: 'user', content: 'question' }),
row({ role: 'assistant', content: 'answer' }),
],
});
expect(md).toContain('## 1. You');
expect(md).toContain('question');
expect(md).toContain('## 2. AI agent');
expect(md).toContain('answer');
});
it('renders a tool part with fenced input/output and the friendly label', () => {
const md = buildChatMarkdown({
title: 'T',
chatId: 'c',
rows: [
row({
role: 'assistant',
content: 'done',
metadata: {
parts: [
{
type: 'tool-getPage',
state: 'output-available',
input: { id: 'p1' },
output: { title: 'Hello' },
},
{ type: 'text', text: 'done' },
],
} as never,
}),
],
});
expect(md).toContain('**Tool: Read page** (`getPage`) — done');
expect(md).toContain('Input:');
expect(md).toContain('"id": "p1"');
expect(md).toContain('Output:');
expect(md).toContain('"title": "Hello"');
});
it('emits a token footer + total when usage is present', () => {
const md = buildChatMarkdown({
title: 'T',
chatId: 'c',
rows: [
row({
role: 'assistant',
content: 'a',
metadata: {
usage: {
inputTokens: 100,
outputTokens: 20,
totalTokens: 120,
reasoningTokens: 8,
},
} as never,
}),
],
});
expect(md).toContain('- Total tokens: 120');
expect(md).toContain(
'_Tokens — in: 100, out: 20, reasoning: 8, total: 120_',
);
});
it('flags a still-streaming (interrupted) row', () => {
const md = buildChatMarkdown({
title: 'T',
chatId: 'c',
rows: [
row({ role: 'assistant', content: 'partial', status: 'streaming' }),
],
});
expect(md).toContain('still being generated');
});
it('does NOT flag a completed row', () => {
const md = buildChatMarkdown({
title: 'T',
chatId: 'c',
rows: [row({ role: 'assistant', content: 'final', status: 'completed' })],
});
expect(md).not.toContain('still being generated');
});
it('renders a legacy NULL-status row (no parts) from plain content', () => {
const md = buildChatMarkdown({
title: 'T',
chatId: 'c',
rows: [
row({ role: 'assistant', content: 'legacy answer', status: null }),
],
});
expect(md).toContain('legacy answer');
expect(md).not.toContain('still being generated');
});
it('renders a persisted error', () => {
const md = buildChatMarkdown({
title: 'T',
chatId: 'c',
rows: [
row({
role: 'assistant',
content: '',
status: 'error',
metadata: { error: '401: Unauthorized' } as never,
}),
],
});
expect(md).toContain('**⚠️ Error:** 401: Unauthorized');
});
it('escapes embedded triple-backtick fences with a longer delimiter', () => {
const md = buildChatMarkdown({
title: 'T',
chatId: 'c',
rows: [
row({
role: 'assistant',
content: 'x',
metadata: {
parts: [
{
type: 'tool-getPage',
state: 'output-available',
output: '```inner```',
},
],
} as never,
}),
],
});
// A 4-backtick fence wraps content that itself contains a 3-backtick run.
expect(md).toContain('````');
});
});

View File

@@ -0,0 +1,296 @@
/**
* Server-side Markdown export for an AI agent chat (#183). The DB is the single
* source of truth: this renders a chat purely from its persisted message rows
* (`AiChatMessage[]` — role / content / metadata.parts / toolCalls / usage).
* Because the assistant row is now persisted UPFRONT and updated per step, an
* interrupted turn is included up to its last finished step.
*
* Ported from the client `utils/chat-markdown.ts`. It is a PURE function (apart
* from `new Date()` for the export timestamp), so it is straightforward to
* unit-test and a future background worker can reuse it.
*
* Only a few fixed role/tool labels are localized via the `lang` param; the
* structural document words (Input/Output/Error/Tokens/...) stay English because
* the output is a technical artifact.
*/
import type { AiChatMessage } from '@docmost/db/types/entity.types';
/** Supported export label languages. Defaults to English. */
export type ExportLang = 'en' | 'ru';
/**
* Normalize an arbitrary client locale code to a supported export language. The
* client sends `i18n.language`, which is a FULL locale tag (e.g. `en-US`,
* `ru-RU`), not a bare `en`/`ru` — so match on the language subtag and fall back
* to English for anything non-Russian.
*/
export function normalizeLang(lang?: string): ExportLang {
return lang?.toLowerCase().startsWith('ru') ? 'ru' : 'en';
}
/** A single AI SDK UIMessage part (text part or a tool part). */
interface ExportPart {
type: string;
text?: string;
state?: string;
toolName?: string;
input?: unknown;
output?: unknown;
errorText?: string;
}
/** Authoritative per-turn usage the server attaches to a message row. */
interface UsageLike {
inputTokens?: number;
outputTokens?: number;
totalTokens?: number;
reasoningTokens?: number;
}
/** Localized label table. Keep the keys identical to the client's i18n keys so
* the two exports read the same. Only role + tool-action labels are localized;
* everything structural is an English constant in the renderer. */
const LABELS: Record<
ExportLang,
{
untitled: string;
aiAgent: string;
you: string;
tools: Record<string, string>;
ranTool: (name: string) => string;
stillGenerating: string;
}
> = {
en: {
untitled: 'Untitled chat',
aiAgent: 'AI agent',
you: 'You',
tools: {
searchPages: 'Searched pages',
getPage: 'Read page',
createPage: 'Created page',
updatePageContent: 'Updated page',
renamePage: 'Renamed page',
movePage: 'Moved page',
deletePage: 'Deleted page (to trash)',
createComment: 'Commented',
resolveComment: 'Resolved comment',
},
ranTool: (name) => `Ran tool ${name}`,
stillGenerating:
'This message is still being generated — the export captured a partial, in-progress response.',
},
ru: {
untitled: 'Без названия',
aiAgent: 'ИИ-агент',
you: 'Вы',
tools: {
searchPages: 'Искал по страницам',
getPage: 'Прочитал страницу',
createPage: 'Создал страницу',
updatePageContent: 'Обновил страницу',
renamePage: 'Переименовал страницу',
movePage: 'Переместил страницу',
deletePage: 'Удалил страницу (в корзину)',
createComment: 'Прокомментировал',
resolveComment: 'Закрыл комментарий',
},
ranTool: (name) => `Выполнил инструмент ${name}`,
stillGenerating:
'Это сообщение всё ещё генерируется — экспорт захватил частичный, незавершённый ответ.',
},
};
/** True for AI SDK tool parts (static `tool-*` or `dynamic-tool`). */
function isToolPart(type: string): boolean {
return type.startsWith('tool-') || type === 'dynamic-tool';
}
/** Extract the tool name from a part `type` of `tool-${name}` (or dynamic). */
function getToolName(part: ExportPart): string {
if (part.type === 'dynamic-tool') return part.toolName ?? '';
return part.type.startsWith('tool-')
? part.type.slice('tool-'.length)
: part.type;
}
/** Map an AI SDK tool-part state to the 3 states the action-log renders. */
function toolRunState(state: string | undefined): 'running' | 'done' | 'error' {
if (state === 'output-error' || state === 'output-denied') return 'error';
if (state === 'output-available') return 'done';
return 'running';
}
/** Resolve a tool's friendly action-log label (localized) from its name. */
function toolLabel(name: string, lang: ExportLang): string {
return LABELS[lang].tools[name] ?? LABELS[lang].ranTool(name);
}
/**
* Stringify an arbitrary tool input/output value for a fenced block. Strings
* pass through as-is; everything else is pretty-printed JSON, falling back to
* `String(value)` if serialization throws (e.g. a circular structure).
*/
function stringify(value: unknown): string {
if (typeof value === 'string') return value;
try {
return JSON.stringify(value, null, 2);
} catch {
return String(value);
}
}
/**
* Wrap `code` in a fenced code block whose backtick delimiter is LONGER than the
* longest backtick run inside the content, so embedded backticks (or a literal
* ``` fence) never break out of the block. Minimum 3 backticks.
*/
function fence(code: string, lang = ''): string {
const runs: string[] = code.match(/`+/g) ?? [];
const longest = runs.reduce((m, s) => Math.max(m, s.length), 0);
const delim = '`'.repeat(Math.max(3, longest + 1));
return `${delim}${lang}\n${code}\n${delim}`;
}
/** Per-row token count, mirroring the header sum in the client window. */
function rowTokens(usage: UsageLike): number {
return (
usage.totalTokens ?? (usage.inputTokens ?? 0) + (usage.outputTokens ?? 0)
);
}
/** Render one message's UIMessage parts into an array of Markdown blocks
* (text blocks + tool blocks). Mirrors the client renderer / MessageItem. */
function renderMessageParts(parts: ExportPart[], lang: ExportLang): string[] {
const out: string[] = [];
for (const part of parts) {
if (part.type === 'text') {
const text = (part.text ?? '').trim();
if (text.length > 0) out.push(text);
continue;
}
if (!isToolPart(part.type)) continue;
const name = getToolName(part);
const label = toolLabel(name, lang);
const state = toolRunState(part.state);
const toolLines: string[] = [`**Tool: ${label}** (\`${name}\`) — ${state}`];
if (part.input !== undefined) {
toolLines.push('Input:');
toolLines.push(fence(stringify(part.input), 'json'));
}
if (part.output !== undefined) {
toolLines.push('Output:');
toolLines.push(fence(stringify(part.output), 'json'));
}
if (part.errorText) {
toolLines.push(`**Error:** ${part.errorText}`);
}
out.push(toolLines.join('\n\n'));
}
return out;
}
/** Resolve a persisted row's parts: prefer the rich persisted parts, else a
* single text part built from the plain-text content (mirrors rowToUiMessage). */
function rowParts(row: AiChatMessage): ExportPart[] {
const meta = (row.metadata ?? {}) as { parts?: ExportPart[] };
return Array.isArray(meta.parts) && meta.parts.length > 0
? meta.parts
: [{ type: 'text', text: row.content ?? '' }];
}
/**
* Serialize a chat to a Markdown string from its persisted rows. Source = DB
* ONLY (no live client state). A row whose `status` is still 'streaming' is an
* interrupted turn that the export captured mid-flight; it is rendered up to its
* last finished step and flagged "still generating".
*/
export function buildChatMarkdown(args: {
title: string | null;
chatId: string;
rows: AiChatMessage[];
// Accepts a full client locale tag (e.g. 'en-US'/'ru-RU'); normalized below.
lang?: string;
}): string {
const { title, chatId, rows } = args;
const lang: ExportLang = normalizeLang(args.lang);
const L = LABELS[lang];
const blocks: string[] = [];
const heading = (title ?? '').trim() || L.untitled;
blocks.push(`# ${heading}`);
const usageOf = (row: AiChatMessage): UsageLike | undefined => {
const meta = (row.metadata ?? {}) as { usage?: UsageLike };
return meta.usage;
};
const errorOf = (row: AiChatMessage): string | undefined => {
const meta = (row.metadata ?? {}) as { error?: string };
return meta.error ?? undefined;
};
// Metadata bullet list. Total tokens is only shown when there is a sum.
const totalTokens = rows.reduce((sum, row) => {
const usage = usageOf(row);
return usage ? sum + rowTokens(usage) : sum;
}, 0);
const meta = [
`- Chat ID: \`${chatId}\``,
`- Exported: ${new Date().toISOString()}`,
`- Messages: ${rows.length}`,
];
if (totalTokens > 0) meta.push(`- Total tokens: ${totalTokens}`);
blocks.push(meta.join('\n'));
rows.forEach((row, index) => {
blocks.push('---');
const roleLabel = row.role === 'assistant' ? L.aiAgent : L.you;
blocks.push(`## ${index + 1}. ${roleLabel}`);
// Created-at kept in source as an HTML comment (out of the rendered prose).
if (row.createdAt) {
const iso =
row.createdAt instanceof Date
? row.createdAt.toISOString()
: String(row.createdAt);
blocks.push(`<!-- ${iso} -->`);
}
blocks.push(...renderMessageParts(rowParts(row), lang));
// A still-'streaming' row is an interrupted/in-progress turn captured by the
// export; record that so the partial answer is not mistaken for complete.
if (row.status === 'streaming') {
blocks.push(`_⏳ ${L.stillGenerating}_`);
}
const error = errorOf(row);
if (error) {
blocks.push(`**⚠️ Error:** ${error}`);
}
const usage = usageOf(row);
if (usage) {
const total = usage.totalTokens ?? rowTokens(usage);
const reasoning =
usage.reasoningTokens && usage.reasoningTokens > 0
? `, reasoning: ${usage.reasoningTokens}`
: '';
blocks.push(
`_Tokens — in: ${usage.inputTokens ?? '?'}, out: ${
usage.outputTokens ?? '?'
}${reasoning}, total: ${total}_`,
);
}
});
// Blank line between blocks so the Markdown renders cleanly.
return blocks.join('\n\n');
}

View File

@@ -26,3 +26,17 @@ export class GetChatMessagesDto {
@IsString()
cursor?: string;
}
/** Export a chat to Markdown (#183). `lang` localizes the few fixed
* role/tool-action labels; defaults to English server-side. */
export class ExportChatDto {
@IsString()
chatId: string;
// A full client locale tag (e.g. 'en-US', 'ru-RU') — normalized server-side to
// a supported export language (see normalizeLang). Accept any string so a
// region-qualified locale is not rejected (the 400 that broke the real client).
@IsOptional()
@IsString()
lang?: string;
}