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* Linking another GitLab account to a signed-in session, from a chat.
*
* The chat receives a sign-in link. The browser first signs in with the session's own
* account and continues only when GitLab reports that same user: otherwise a link opened by
* another person would attach their GitLab account to this session. Then it signs in with
* the account to link, and the callback stores that account with the session. That second
* step completes only in the browser that passed the first (a cookie it was given there):
* its sign-in URL forwarded to someone else would otherwise link their account. Every step
* is a stored, single-use, expiring flow, so it works when requests land on different
* replicas.
*/
import { createHash, timingSafeEqual } from 'node:crypto';
import type { Response } from 'express';
import { GITLAB_BASE_URL } from '../config';
import type { OAuthConfig } from '../oauth/config';
import { isOAuthEnabled, loadOAuthConfig } from '../oauth/config';
import { sessionStore } from '../oauth/session-store';
import { getTokenContext } from '../oauth/token-context';
import { oauthAppFor, selectableOAuthApps } from '../oauth/instance-app';
import type { GitLabOAuthApp } from '../oauth/oauth-app';
import {
buildGitLabAuthUrl,
getGitLabUser,
revokeGitLabToken,
GitLabOAuthHttpError,
} from '../oauth/gitlab-device-flow';
import { AccountLinkFlowUnavailableError, exchangeFlowCode } from '../oauth/code-exchange';
import { discardAuthCodeFlow } from '../oauth/grant-revocation';
import {
claimSessionLease,
withFreshGitLabToken,
GitLabGrantRevokedError,
} from '../oauth/gitlab-token-refresh';
import { grantedGitlabScopes } from '../oauth/granted-scopes';
import {
calculateTokenExpiry,
generateRandomString,
isTokenExpiringSoon,
} from '../oauth/token-utils';
import type { AccountLinkStep, AuthCodeFlowState, OAuthSession } from '../oauth/types';
import { normalizeInstanceUrl } from '../utils/url';
import { escapeHtml } from '../utils/html';
import { logInfo, logWarn, truncateId } from '../logger';
import { AccountUnavailableError } from './chat-accounts';
/** How long a link stays usable; long enough to sign in, short enough not to linger. */
const LINK_TTL_MS = 10 * 60 * 1000;
/** Passes over the stored account before a link gives up and asks for a reload. */
const STORE_ATTEMPTS = 20;
/** Wait between passes while another link or a token refresh holds the account's lease. */
const STORE_RETRY_MS = 100;
/** How long a replacement holds the account: a lookup and one write. */
const REPLACE_LEASE_MS = 15_000;
/**
* How long a link holds its session while it completes: the check, the store (with the
* account's own lease and its passes) and spending the link.
*/
const LINK_COMPLETION_LEASE_MS = REPLACE_LEASE_MS + STORE_ATTEMPTS * STORE_RETRY_MS + 5_000;
/**
* Storage id of an account linked to a session: one per session, instance and user. The
* session id holds no colon and the user id is numeric, so the parts never run together.
*/
function linkedAccountId(sessionId: string, instance: string, userId: number): string {
return `linked:${sessionId}:${userId}@${instance}`;
}
/** The URL elicitation through which a chat's client opened a link. */
export interface LinkElicitation {
mcpSessionId: string;
elicitationId: string;
}
export interface AccountLinkStart {
/** Where the user signs in; opened in the browser, never shown to anyone else. */
url: string;
instanceUrl: string;
instanceLabel?: string;
expiresAt: number;
}
function callbackUri(config: OAuthConfig): string {
return `${config.issuer}/oauth/callback`;
}
function sha256Hex(value: string): string {
return createHash('sha256').update(value).digest('hex');
}
/** Cookie of one link's connect step, named after its state so parallel links coexist. */
function bindingCookieName(state: string): string {
return `gitlab_mcp_link_${sha256Hex(state).slice(0, 16)}`;
}
/** Hand the browser that passed `verify` the nonce its connect step checks. */
function bindBrowser(res: Response, config: OAuthConfig, state: string, nonce: string): void {
res.cookie(bindingCookieName(state), nonce, {
httpOnly: true,
// Sent on GitLab's top-level redirect back to the callback, never on cross-site requests.
sameSite: 'lax',
secure: new URL(config.issuer).protocol === 'https:',
path: new URL(callbackUri(config)).pathname,
maxAge: LINK_TTL_MS,
});
}
/** Whether the request completing a connect step comes from the browser bound to it. */
function fromBoundBrowser(res: Response, state: string, link: AccountLinkStep): boolean {
const name = bindingCookieName(state);
const nonce = (res.req?.headers.cookie ?? '')
.split(';')
.map((pair) => pair.trim().split('='))
.find(([key]) => key === name)?.[1];
if (!nonce || !link.browserBinding) return false;
const expected = Buffer.from(link.browserBinding, 'hex');
const actual = Buffer.from(sha256Hex(nonce), 'hex');
return expected.length === actual.length && timingSafeEqual(expected, actual);
}
function requestedScopes(app: GitLabOAuthApp): string[] {
return app.scopes.split(/[,\s]+/).filter(Boolean);
}
/** A stored step of a link: its state and the GitLab sign-in URL that continues it. */
interface StoredLinkStep {
state: string;
url: string;
}
/** Store one step of a link. */
async function storeLinkStep(
config: OAuthConfig,
session: OAuthSession,
app: GitLabOAuthApp,
link: AccountLinkStep,
): Promise<StoredLinkStep> {
const state = generateRandomString(32);
const flow: AuthCodeFlowState = {
requestedGitlabScopes: requestedScopes(app),
selectedInstance: app.baseUrl,
selectedInstanceLabel: app.label,
clientId: session.clientId,
// A link signs no MCP client in: no client PKCE, state or redirect.
codeChallenge: '',
codeChallengeMethod: 'S256',
clientState: '',
internalState: state,
clientRedirectUri: '',
callbackUri: callbackUri(config),
expiresAt: Date.now() + LINK_TTL_MS,
scopes: [],
link,
};
await sessionStore.storeAuthCodeFlow(state, flow);
return { state, url: buildGitLabAuthUrl(config, callbackUri(config), state, app) };
}
/**
* Start linking an account on `instance` (default: the session's own instance) to the
* connection's session; returns the sign-in link for the user. With `elicitation`, the chat
* whose client opens the link is told when the account is linked.
*/
export async function startAccountLink(
instance: string | undefined,
elicitation?: LinkElicitation,
): Promise<AccountLinkStart> {
const config = loadOAuthConfig();
if (!isOAuthEnabled() || !config) {
throw new AccountUnavailableError(
'Linking accounts needs a server that signs users in with GitLab; with a static token, configure the instance with a token instead.',
);
}
if (!sessionStore.linksAccounts()) {
throw new AccountUnavailableError(
'The session storage of this server cannot keep linked accounts; update the database package.',
);
}
const context = getTokenContext();
const session = context ? await sessionStore.getSession(context.sessionId) : undefined;
if (!session) {
throw new AccountUnavailableError('This connection is not signed in to GitLab.');
}
const own = await oauthAppFor(config, session.gitlabApiUrl);
if (!own) {
throw new AccountUnavailableError(
'The instance this connection signed in with is no longer configured; sign in again.',
);
}
const target = instance ? await oauthAppFor(config, normalizeInstanceUrl(instance)) : own;
if (!target) {
const known = (await selectableOAuthApps(config)).map((app) => app.baseUrl).join(', ');
throw new AccountUnavailableError(
`No GitLab instance ${instance} is configured for sign-in; configured: ${known}.`,
);
}
const { url } = await storeLinkStep(config, session, own, {
sessionId: session.id,
stage: 'verify',
instance: target.baseUrl,
instanceLabel: target.label,
...elicitation,
});
logInfo('Account link started', {
sessionId: truncateId(session.id),
instance: target.baseUrl,
});
return {
url,
instanceUrl: target.baseUrl,
instanceLabel: target.label,
expiresAt: Date.now() + LINK_TTL_MS,
};
}
/** A button on a link page that continues to `href`. */
interface LinkPageAction {
href: string;
label: string;
}
/** Page the browser ends on; `message` is plain text. */
function linkPage(
res: Response,
status: number,
title: string,
message: string,
action?: LinkPageAction,
): void {
const button = action
? `\n <p><a class="button" href="${escapeHtml(action.href)}">${escapeHtml(action.label)}</a></p>`
: '';
res.status(status).type('html').send(`<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>GitLab MCP - ${escapeHtml(title)}</title>
<style>
body { font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif; max-width: 600px; margin: 0 auto; padding: 40px 20px; background: #f5f5f5; }
.container { background: white; padding: 40px; border-radius: 12px; box-shadow: 0 2px 10px rgba(0,0,0,0.1); }
h1 { color: #333; font-size: 24px; margin: 0 0 16px; }
p { color: #555; line-height: 1.5; }
.button { display: inline-block; padding: 10px 20px; background: #6b4fbb; color: white; border-radius: 6px; text-decoration: none; }
</style>
</head>
<body>
<div class="container">
<h1>${escapeHtml(title)}</h1>
<p>${escapeHtml(message)}</p>${button}
</div>
</body>
</html>`);
}
/** End a link the browser cannot complete. */
export function failAccountLink(res: Response, message: string): void {
linkPage(res, 400, 'Account not linked', message);
}
async function revokeQuietly(
token: string,
config: OAuthConfig,
app: GitLabOAuthApp,
): Promise<void> {
try {
await revokeGitLabToken(token, config, app);
} catch (error: unknown) {
logWarn('Failed to revoke a GitLab token of an account link', { err: error as Error });
}
}
/** First step: the browser proves it belongs to the session's own user, then goes on. */
async function verifyOwnAccount(
res: Response,
state: string,
flow: AuthCodeFlowState,
link: AccountLinkStep,
code: string,
config: OAuthConfig,
session: OAuthSession,
): Promise<void> {
const own = await oauthAppFor(config, flow.selectedInstance);
const target = await oauthAppFor(config, link.instance);
if (!own || !target) {
failAccountLink(res, 'A GitLab instance of this link is no longer configured.');
return;
}
const tokens = flow.gitlabTokens ?? (await exchangeFlowCode(state, flow, code, config, own));
const user = await getGitLabUser(tokens.access_token, own.baseUrl);
if (user.id !== session.gitlabUserId) {
const consumed = await sessionStore.consumeAuthCodeFlow(state);
await revokeQuietly(tokens.access_token, config, own);
if (!consumed) {
failAccountLink(res, 'This link was already used. Ask for a new one in the chat.');
return;
}
logWarn('Account link refused: the browser signed in as another user', {
sessionId: truncateId(session.id),
});
failAccountLink(
res,
`This link belongs to ${session.gitlabUsername}, but GitLab signed you in as ${user.username}. ` +
'Only the person who asked for the link can complete it.',
);
return;
}
// The next step is stored before this one is spent: a failed write leaves this step and
// its tokens in place, so reloading the page retries it. It keeps only a digest of the
// nonce this browser receives below.
const nonce = generateRandomString(32);
const next = await storeLinkStep(config, session, target, {
...link,
stage: 'connect',
browserBinding: sha256Hex(nonce),
});
const consumed = await sessionStore.consumeAuthCodeFlow(state);
// Only the identity was needed; this grant must not outlive the check. It is a grant of its
// own, never the session's: GitLab leaves Doorkeeper's reuse_access_token off (and hashes
// token secrets, which rules it out), so every code exchange issues a new token.
await revokeQuietly(tokens.access_token, config, own);
if (!consumed) {
await sessionStore.deleteAuthCodeFlow(next.state);
failAccountLink(res, 'This link was already used. Ask for a new one in the chat.');
return;
}
bindBrowser(res, config, next.state, nonce);
if (normalizeInstanceUrl(target.baseUrl) !== normalizeInstanceUrl(own.baseUrl)) {
res.redirect(next.url);
return;
}
// On its own instance the browser is still signed in to GitLab as the account just
// verified, which GitLab would authorize again; the user signs in with the other one first,
// in this browser (another one, a private window included, lacks the cookie of this step).
linkPage(
res,
200,
'Sign in with the account to link',
`GitLab confirmed you as ${user.username}. To link another account on ${target.label ?? new URL(target.baseUrl).host}, ` +
'sign out of GitLab in this browser (or switch to that account there), then continue here.',
{ href: next.url, label: 'Continue to GitLab sign-in' },
);
}
type LinkedGrant = Pick<
OAuthSession,
'gitlabAccessToken' | 'gitlabRefreshToken' | 'gitlabTokenExpiry' | 'gitlabScopes'
>;
/** The account a link stores with a session, and the grant it stores. */
interface LinkedAccountWrite {
session: OAuthSession;
link: AccountLinkStep;
user: { id: number; username: string };
instance: string;
grant: LinkedGrant;
}
/** Ownership evidence checked by storage in the same commit that spends the flow. */
interface LinkFence {
internalState: string;
primaryLeaseUntil: number;
}
/** What one pass over the stored account achieved; `wait` asks for a pause before the next. */
type StorePass =
| { done: true; displaced: string | undefined }
| { done: false; wait: boolean; refresh?: OAuthSession; retry?: true };
type StoreResult =
| { done: true; displaced: string | undefined }
| { done: false; refresh: OAuthSession }
| { done: false; retry: true };
/** The exact refresh credential prepared by this completion's preceding refresh attempt. */
interface PreparedGrant {
refreshToken: string;
unusable: boolean;
}
async function findLinkedAccount(write: LinkedAccountWrite): Promise<OAuthSession | undefined> {
return (await sessionStore.getLinkedSessions(write.session.id)).find(
(row) =>
normalizeInstanceUrl(row.gitlabApiUrl ?? GITLAB_BASE_URL) === write.instance &&
row.gitlabUserId === write.user.id,
);
}
/** Store the account's row; another pass is needed when another link stored it meanwhile. */
async function createLinkedAccount(
write: LinkedAccountWrite,
fence: LinkFence,
): Promise<StorePass> {
const { session, link, user, instance, grant } = write;
const now = Date.now();
// The id follows from the session and the account, so a concurrent link of the same
// account collides on it in storage instead of storing the account twice.
const committed = await sessionStore.commitLinkedAccount({
...fence,
account: {
id: linkedAccountId(session.id, instance, user.id),
mcpAccessToken: '',
mcpRefreshToken: '',
mcpTokenExpiry: 0,
...grant,
gitlabUserId: user.id,
gitlabUsername: user.username,
gitlabApiUrl: instance,
instanceLabel: link.instanceLabel,
clientId: session.clientId,
scopes: [],
linkedToSessionId: session.id,
createdAt: now,
updatedAt: now,
},
});
return committed
? { done: true, displaced: undefined }
: { done: false, wait: false, retry: true };
}
/** Give the stored account the new grant while holding its lease. */
async function replaceLinkedGrant(
write: LinkedAccountWrite,
stored: OAuthSession,
preparedGrant: PreparedGrant | undefined,
fence: LinkFence,
): Promise<StorePass> {
const now = Date.now();
const leaseUntil = now + REPLACE_LEASE_MS;
const claimed = await sessionStore.claimGitLabRefresh(
stored.id,
stored.gitlabRefreshToken,
now,
leaseUntil,
);
if (!claimed) {
// Another link or a token refresh is changing the row: wait for its turn to end.
return { done: false, wait: true };
}
try {
if (
stored.gitlabRefreshToken !== write.grant.gitlabRefreshToken &&
isTokenExpiringSoon(stored.gitlabTokenExpiry) &&
(preparedGrant?.refreshToken !== stored.gitlabRefreshToken ||
(!preparedGrant.unusable && stored.gitlabTokenExpiry <= Date.now()))
) {
// Doorkeeper 5.6.6 skips expired access tokens on revoke. Keep both credentials
// until refreshed. A just-refreshed short-lived grant need not refresh again,
// but recheck its actual expiry under the lease after waiting for the primary.
return { done: false, wait: false, refresh: stored };
}
// Read before the update: a backend may hand out the stored record, which it changes.
// A refused refresh does not prove this access token is unusable; still revoke it.
const displaced = stored.gitlabAccessToken;
const committed = await sessionStore.commitLinkedAccount({
...fence,
account: {
...stored,
...write.grant,
gitlabUsername: write.user.username,
linkedToSessionId: write.session.id,
},
existing: { refreshToken: stored.gitlabRefreshToken, leaseUntil },
});
return committed ? { done: true, displaced } : { done: false, wait: false, retry: true };
} finally {
await sessionStore.releaseGitLabRefresh(stored.id, leaseUntil).catch(() => undefined);
}
}
/**
* Store the account with the session, or give an account linked before the new grant;
* returns the access token of the grant it displaced, if any. Replacements of one account
* take turns under the lease a GitLab token refresh holds (claimed only while the row still
* holds the refresh token read), so each knows exactly which grant it displaced.
*/
async function storeLinkedAccount(
write: LinkedAccountWrite,
preparedGrant: PreparedGrant | undefined,
fence: LinkFence,
attempt = 1,
): Promise<StoreResult> {
const stored = await findLinkedAccount(write);
const pass = stored
? await replaceLinkedGrant(write, stored, preparedGrant, fence)
: await createLinkedAccount(write, fence);
if (pass.done) return pass;
if (pass.retry) return { done: false, retry: true };
if (pass.refresh) return { done: false, refresh: pass.refresh };
if (attempt >= STORE_ATTEMPTS) {
throw new Error('The linked account is being changed elsewhere');
}
Eif (pass.wait) await new Promise((resolve) => setTimeout(resolve, STORE_RETRY_MS));
return storeLinkedAccount(write, preparedGrant, fence, attempt + 1);
}
/** How a link's completion ended, and the grant its store displaced, if any. */
interface LinkCompletion {
outcome: 'completed' | 'spent' | 'signed-out';
replacedToken?: string;
}
/**
* Store the account and spend the link. The completions of the session's links take turns
* under its lease, from the check that this link is still unspent until it is spent: a
* delivery that lost to another delivery of the same callback stores nothing, so it cannot
* put back a grant a later link replaced and ended, and a discard of the expired flow
* decides whether its grant is the account's under the same lease. A revocation of the
* session holds the lease from before it reads the linked accounts until it deletes them,
* so it either sees this account or this link sees the session gone.
*/
async function completeUnderSessionLease(
state: string,
write: LinkedAccountWrite,
preparedGrant: PreparedGrant | undefined,
): Promise<LinkCompletion | { outcome: 'refresh'; account: OAuthSession } | { outcome: 'retry' }> {
const { session, instance, user } = write;
const turn = await claimSessionLease(session.id, LINK_COMPLETION_LEASE_MS);
if (turn === undefined) {
await sessionStore.consumeAuthCodeFlow(state);
return { outcome: 'signed-out' };
}
try {
const flow = await sessionStore.getAuthCodeFlow(state);
if (!flow || flow.expiresAt <= Date.now()) return { outcome: 'spent' };
const result = await storeLinkedAccount(write, preparedGrant, {
internalState: state,
primaryLeaseUntil: turn,
});
if (!result.done) {
if ('retry' in result) return { outcome: 'retry' };
return { outcome: 'refresh', account: result.refresh };
}
const replacedToken = result.displaced;
// A session removed without its lease (storage cleanup) leaves the row behind.
if (!(await sessionStore.getSession(session.id))) {
await sessionStore.deleteSession(linkedAccountId(session.id, instance, user.id));
return { outcome: 'signed-out', replacedToken };
}
return { outcome: 'completed', replacedToken };
} finally {
await sessionStore.releaseGitLabRefresh(session.id, turn).catch(() => undefined);
}
}
/** Refresh a displaced grant outside the primary lease, then retry the serialized store. */
async function completeWithLiveDisplacedGrant(
state: string,
write: LinkedAccountWrite,
config: OAuthConfig,
): Promise<LinkCompletion> {
let preparedGrant: PreparedGrant | undefined;
for (let attempt = 0; attempt < STORE_ATTEMPTS; attempt++) {
const result = await completeUnderSessionLease(state, write, preparedGrant);
if (result.outcome === 'retry') continue;
if (result.outcome !== 'refresh') return result;
const spent = result.account.gitlabRefreshToken;
try {
const refreshed = await withFreshGitLabToken(result.account, config);
Eif (refreshed) {
preparedGrant = { refreshToken: refreshed.gitlabRefreshToken, unusable: false };
}
} catch (error: unknown) {
// Only invalid_grant proves this particular credential is already unusable.
// A missing application or a temporary failure must leave the old pair stored.
if (
!(error instanceof GitLabGrantRevokedError) ||
!(error.cause instanceof GitLabOAuthHttpError) ||
error.cause.oauthError !== 'invalid_grant'
) {
throw error;
}
preparedGrant = { refreshToken: spent, unusable: true };
}
}
throw new Error('The linked account is being changed elsewhere');
}
/** Second step: store the signed-in account with the session, or refresh it when linked. */
async function connectAccount(
res: Response,
state: string,
flow: AuthCodeFlowState,
link: AccountLinkStep,
code: string,
config: OAuthConfig,
session: OAuthSession,
): Promise<void> {
// Checked before the code is exchanged: a browser this step was forwarded to gets no
// grant at all, and the step is spent so the forwarded link cannot be retried.
if (!fromBoundBrowser(res, state, link)) {
logWarn('Account link refused: continued in another browser', {
sessionId: truncateId(session.id),
});
await discardAuthCodeFlow(state, flow, config);
failAccountLink(
res,
'Continue the link in the browser where you confirmed your own account; a link cannot be passed on. Ask for a new one in the chat.',
);
return;
}
const app = await oauthAppFor(config, flow.selectedInstance);
if (!app) {
failAccountLink(res, 'The GitLab instance of this link is no longer configured.');
return;
}
const tokens = flow.gitlabTokens ?? (await exchangeFlowCode(state, flow, code, config, app));
const user = await getGitLabUser(tokens.access_token, app.baseUrl);
const instance = normalizeInstanceUrl(app.baseUrl);
const ownInstance = normalizeInstanceUrl(session.gitlabApiUrl ?? GITLAB_BASE_URL);
if (instance === ownInstance && user.id === session.gitlabUserId) {
await sessionStore.consumeAuthCodeFlow(state);
await revokeQuietly(tokens.access_token, config, app);
failAccountLink(
res,
`GitLab signed you in as ${user.username} again, the account this connection already uses. ` +
'To link another account, sign out of GitLab or sign in with the other account first.',
);
return;
}
const { outcome, replacedToken } = await completeWithLiveDisplacedGrant(
state,
{
session,
link,
user,
instance,
grant: {
gitlabAccessToken: tokens.access_token,
gitlabRefreshToken: tokens.refresh_token,
gitlabTokenExpiry: calculateTokenExpiry(tokens.expires_in),
gitlabScopes: grantedGitlabScopes(tokens.scope, flow.requestedGitlabScopes),
},
},
config,
);
// The displaced grant is no longer stored. A grant this link already stored is not one.
if (replacedToken && replacedToken !== tokens.access_token) {
await revokeQuietly(replacedToken, config, app);
}
if (outcome === 'signed-out') {
await revokeQuietly(tokens.access_token, config, app);
failAccountLink(res, 'The connection that asked for this link has signed out.');
return;
}
if (outcome === 'spent') {
failAccountLink(res, 'This link was already completed or has expired.');
return;
}
res.clearCookie(bindingCookieName(state), { path: new URL(callbackUri(config)).pathname });
const label = `${user.username} @ ${link.instanceLabel ?? new URL(instance).host}`;
logInfo('Account linked', { sessionId: truncateId(session.id), instance });
linkPage(
res,
200,
'Account linked',
`${label} is linked to your GitLab MCP connection. Return to the chat and switch to it with manage_context switch_account.`,
);
await announceLinked(link);
}
/**
* Tell the chat whose client opened the link (MCP URL elicitation) that it completed. The
* client's answer to the elicitation only meant consent to open it; this is how it learns
* the outcome. Best effort: the callback may reach a replica that does not hold the chat.
*/
async function announceLinked(link: AccountLinkStep): Promise<void> {
if (!link.mcpSessionId || !link.elicitationId) return;
try {
const { getSessionManager } = await import('../session-manager');
await getSessionManager().notifyElicitationComplete(link.mcpSessionId, link.elicitationId);
} catch (error: unknown) {
// The page is already sent: a failed announcement must not reach the error page.
logWarn('Could not announce a completed account link', { err: error as Error });
}
}
/** Complete a step of an account link from GitLab's callback. */
export async function completeAccountLink(
res: Response,
state: string,
flow: AuthCodeFlowState,
code: string,
config: OAuthConfig,
): Promise<void> {
const link = flow.link as AccountLinkStep;
if (Date.now() > flow.expiresAt) {
await discardAuthCodeFlow(state, flow, config);
failAccountLink(res, 'This link expired. Ask for a new one in the chat.');
return;
}
try {
const session = await sessionStore.getSession(link.sessionId);
if (!session) {
await discardAuthCodeFlow(state, flow, config);
failAccountLink(res, 'The connection that asked for this link has signed out.');
return;
}
if (link.stage === 'verify') {
await verifyOwnAccount(res, state, flow, link, code, config, session);
} else {
await connectAccount(res, state, flow, link, code, config, session);
}
} catch (error: unknown) {
logWarn('Account link failed', { err: error as Error });
if (error instanceof AccountLinkFlowUnavailableError) {
failAccountLink(
res,
'This link was already used or has expired. Ask for a new one in the chat.',
);
return;
}
// The flow is kept unless it was completed, so reloading the page retries it.
linkPage(
res,
500,
'Account not linked',
'Linking failed for a temporary reason; reload this page to try again.',
);
}
}
|