oai-reverse-proxy/src/proxy/middleware/request/count-prompt-tokens.ts

48 lines
1.5 KiB
TypeScript

import { RequestPreprocessor } from "./index";
import { countTokens, OpenAIPromptMessage } from "../../../shared/tokenization";
import { assertNever } from "../../../shared/utils";
/**
* Given a request with an already-transformed body, counts the number of
* tokens and assigns the count to the request.
*/
export const countPromptTokens: RequestPreprocessor = async (req) => {
const service = req.outboundApi;
let result;
switch (service) {
case "openai": {
req.outputTokens = req.body.max_tokens;
const prompt: OpenAIPromptMessage[] = req.body.messages;
result = await countTokens({ req, prompt, service });
break;
}
case "openai-text": {
req.outputTokens = req.body.max_tokens;
const prompt: string = req.body.prompt;
result = await countTokens({ req, prompt, service });
break;
}
case "anthropic": {
req.outputTokens = req.body.max_tokens_to_sample;
const prompt: string = req.body.prompt;
result = await countTokens({ req, prompt, service });
break;
}
case "google-palm": {
req.outputTokens = req.body.maxOutputTokens;
const prompt: string = req.body.prompt.text;
result = await countTokens({ req, prompt, service });
break;
}
default:
assertNever(service);
}
req.promptTokens = result.token_count;
// TODO: Remove once token counting is stable
req.log.debug({ result: result }, "Counted prompt tokens.");
req.debug = req.debug ?? {};
req.debug = { ...req.debug, ...result };
};