| import { request } from "undici"; |
|
|
| const API_BASE = process.env.LLM_API_BASE ?? "https://api.openai.com"; |
| const API_KEY = process.env.LLM_API_KEY ?? ""; |
| const MODEL = process.env.LLM_MODEL ?? "gpt-4o-mini"; |
|
|
| export async function streamChatCompletion( |
| messages: Array<{ role: string; content: string }>, |
| onToken: (token: string) => void |
| ) { |
| if (!API_KEY) { |
| throw new Error("Missing LLM_API_KEY environment variable."); |
| } |
|
|
| const payload = { |
| model: MODEL, |
| messages, |
| stream: true, |
| temperature: 0.3 |
| }; |
|
|
| const { body, statusCode } = await request(`${API_BASE}/v1/chat/completions`, { |
| method: "POST", |
| headers: { |
| "Authorization": `Bearer ${API_KEY}`, |
| "Content-Type": "application/json" |
| }, |
| body: JSON.stringify(payload) |
| }); |
|
|
| if (statusCode < 200 || statusCode >= 300) { |
| const errorText = await body.text(); |
| throw new Error(`LLM request failed (${statusCode}): ${errorText.slice(0, 200)}`); |
| } |
|
|
| const reader = body.getReader(); |
| const decoder = new TextDecoder(); |
| let buffer = ""; |
|
|
| while (true) { |
| const { value, done } = await reader.read(); |
| if (done) break; |
| buffer += decoder.decode(value, { stream: true }); |
|
|
| let boundary = buffer.indexOf("\n\n"); |
| while (boundary !== -1) { |
| const chunk = buffer.slice(0, boundary).trim(); |
| buffer = buffer.slice(boundary + 2); |
| if (chunk.startsWith("data:")) { |
| const data = chunk.replace(/^data:\s*/, "").trim(); |
| if (data === "[DONE]") return; |
| try { |
| const parsed = JSON.parse(data); |
| const delta = parsed.choices?.[0]?.delta?.content; |
| if (delta) onToken(delta); |
| } catch { |
| |
| } |
| } |
| boundary = buffer.indexOf("\n\n"); |
| } |
| } |
| }
|
|
|
