openpencil/apps/web/server/api/ai/provider-models.ts
Kayshen-X f61ca2072b fix(ai): unwrap fetch error.cause for actionable network failures
Custom OpenAI-compatible providers surfaced Node's opaque
`TypeError: fetch failed` whenever the upstream HTTP call failed
(#121) — DNS, TLS handshake, connection refused, timeout — all
collapsed to the same useless string. The actual reason was already
on `error.cause` as a SystemError but never reached the user.

Add `formatFetchError()` that walks the cause chain (including
AggregateError emitted when undici tries multiple A records and each
attempt fails) and prefixes the SystemError code so users see
`ENOTFOUND: getaddrinfo ENOTFOUND api.foo.com` or
`ECONNREFUSED: connect ECONNREFUSED 127.0.0.1:443` instead of
`fetch failed`. Wire it into the model-list proxy (most common
trigger from the AI Settings dialog) and the builtin chat stream.

Closes #121
2026-04-26 19:20:32 +08:00

68 lines
2.1 KiB
TypeScript

import { defineEventHandler, readBody } from 'h3';
import { buildProviderModelsURL, formatFetchError, normalizeOptionalBaseURL } from './provider-url';
interface ProviderModelsBody {
baseURL: string;
apiKey?: string;
}
interface ModelEntry {
id: string;
name: string;
}
/**
* POST /api/ai/provider-models
* Proxies model list requests to external providers to avoid CORS issues.
* Body: { baseURL: string, apiKey?: string }
* Returns: { models: Array<{ id: string, name: string }> }
*/
export default defineEventHandler(async (event) => {
const body = await readBody<ProviderModelsBody>(event);
const normalizedBaseURL = normalizeOptionalBaseURL(body?.baseURL);
const apiKey = body?.apiKey;
if (!normalizedBaseURL) {
return { models: [], error: 'baseURL is required' };
}
const url = buildProviderModelsURL(normalizedBaseURL);
const headers: Record<string, string> = {
Accept: 'application/json',
};
if (apiKey) {
headers.Authorization = `Bearer ${apiKey}`;
}
try {
const res = await fetch(url, { headers, signal: AbortSignal.timeout(10_000) });
if (!res.ok) {
const text = await res.text().catch(() => '');
return { models: [], error: `Provider returned ${res.status}: ${text.slice(0, 200)}` };
}
const json = (await res.json()) as Record<string, unknown>;
// Handle different response formats: { data: [...] } (OpenAI), { models: [...] }, or [...]
const rawModels = Array.isArray(json.data)
? json.data
: Array.isArray(json.models)
? json.models
: Array.isArray(json)
? json
: null;
if (!rawModels) {
return { models: [], error: 'Unexpected response format (no model array found)' };
}
const models: ModelEntry[] = (rawModels as Array<Record<string, unknown>>)
.filter((m) => m.id)
.map((m) => ({
id: String(m.id),
name: (typeof m.name === 'string' ? m.name : '') || String(m.id),
}))
.sort((a, b) => a.name.localeCompare(b.name));
return { models };
} catch (err) {
return { models: [], error: formatFetchError(err) };
}
});