src/lib/server/endpoints/openai/endpointOai.ts

import { z } from "zod";
import { openAICompletionToTextGenerationStream } from "./openAICompletionToTextGenerationStream";
import { openAIChatToTextGenerationStream } from "./openAIChatToTextGenerationStream";
import { buildPrompt } from "$lib/buildPrompt";
import { OPENAI_API_KEY } from "$env/static/private";
import type { Endpoint } from "../endpoints";

export const endpointOAIParametersSchema = z.object({
	weight: z.number().int().positive().default(1),
	model: z.any(),
	type: z.literal("openai"),
	baseURL: z.string().url().default("https://api.openai.com/v1"),
	apiKey: z.string().default(OPENAI_API_KEY ?? "sk-"),
	completion: z
		.union([z.literal("completions"), z.literal("chat_completions")])
		.default("chat_completions"),
	defaultHeaders: z.record(z.string()).optional(),
	defaultQuery: z.record(z.string()).optional(),
});

export async function endpointOai(
	input: z.input<typeof endpointOAIParametersSchema>
): Promise<Endpoint> {
	const { baseURL, apiKey, completion, model, defaultHeaders, defaultQuery } =
		endpointOAIParametersSchema.parse(input);
	let OpenAI;
	try {
		OpenAI = (await import("openai")).OpenAI;
	} catch (e) {
		throw new Error("Failed to import OpenAI", { cause: e });
	}

	const openai = new OpenAI({
		apiKey: apiKey ?? "sk-",
		baseURL,
		defaultHeaders,
		defaultQuery,
	});

	if (completion === "completions") {
		return async ({ messages, preprompt, continueMessage }) => {
			const prompt = await buildPrompt({
				messages,
				continueMessage,
				preprompt,
				model,
			});

			return openAICompletionToTextGenerationStream(
				await openai.completions.create({
					model: model.id ?? model.name,
					prompt,
					stream: true,
					max_tokens: model.parameters?.max_new_tokens,
					stop: model.parameters?.stop,
					temperature: model.parameters?.temperature,
					top_p: model.parameters?.top_p,
					frequency_penalty: model.parameters?.repetition_penalty,
				})
			);
		};
	} else if (completion === "chat_completions") {
		return async ({ messages, preprompt }) => {
			let messagesOpenAI = messages.map((message) => ({
				role: message.from,
				content: message.content,
			}));

			if (messagesOpenAI?.[0]?.role !== "system") {
				messagesOpenAI = [{ role: "system", content: preprompt ?? "" }, ...messagesOpenAI];
			}

			return openAIChatToTextGenerationStream(
				await openai.chat.completions.create({
					model: model.id ?? model.name,
					messages: messagesOpenAI,
					stream: true,
					max_tokens: model.parameters?.max_new_tokens,
					stop: model.parameters?.stop,
					temperature: model.parameters?.temperature,
					top_p: model.parameters?.top_p,
					frequency_penalty: model.parameters?.repetition_penalty,
				})
			);
		};
	} else {
		throw new Error("Invalid completion type");
	}
}