openai-rs 0.1.1

A Rust implementation of OpenAI
Documentation
use std::borrow::Cow;
use std::collections::HashMap;
use serde::Serialize;
use hyper::{Body, Request};
use crate::endpoints::request::Endpoint;

/// Given a prompt, the response will return one or more predicted completions,
/// and can also return the probabilities of alternative tokens at each position.
#[derive(Debug, Clone, Serialize)]
pub struct Completion<'a> {
    /// The prompt(s) to generate completions for, encoded as a string, array of strings,
    /// array of tokens, or array of token arrays.
    /// Note that `<|endoftext|>` is the document separator that the model sees during training,
    /// so if a prompt is not specified the model will generate as if from the beginning of a new document.
    pub prompt: Option<Cow<'a, str>>,

    /// The suffix that comes after a completion of inserted text.
    pub suffix: Option<Cow<'a, str>>,

    /// The maximum number of tokens to generate in the completion.
    /// The token count of your prompt plus max_tokens cannot exceed the model's context length.
    /// Most models have a context length of 2048 tokens (except for the newest models, which support 4096).
    pub max_tokens: u32,

    /// What sampling temperature to use. Higher values means the model will take more risks.
    /// Try 0.9 for more creative applications, and 0 (argmax sampling) for ones with a well-defined answer.
    /// We generally recommend altering this or top_p but not both.
    pub temperature: f32,

    /// An alternative to sampling with temperature, called nucleus sampling, where the model
    /// considers the results of the tokens with top_p probability mass. So 0.1 means only
    /// the tokens comprising the top 10% probability mass are considered.
    /// We generally recommend altering this or temperature but not both.
    pub top_p: f32,

    /// How many completions to generate for each prompt.
    /// Note: Because this parameter generates many completions,
    /// it can quickly consume your token quota. Use carefully and ensure that
    /// you have reasonable settings for max_tokens and stop.
    pub n: u32,

    /// Whether to stream back partial progress.
    /// If set, tokens will be sent as data-only server-sent events as they become available,
    /// with the stream terminated by a data: `[DONE]` message.
    pub stream: bool,

    /// Include the log probabilities on the logprobs most likely tokens, as well the chosen tokens.
    /// For example, if logprobs is 5, the API will return a list of the 5 most likely tokens.
    /// The API will always return the logprob of the sampled token,
    /// so there may be up to logprobs+1 elements in the response.
    /// The maximum value for logprobs is 5.
    /// If you need more than this, please contact support@openai.com and describe your use case.
    pub logprobs: Option<u32>,

    /// Echo back the prompt in addition to the completion
    pub echo: bool,

    /// Up to 4 sequences where the API will stop generating further tokens.
    /// The returned text will not contain the stop sequence.
    pub stop: Option<Vec<Cow<'a, str>>>,

    /// Number between -2.0 and 2.0. Positive values penalize new tokens based on whether they
    /// appear in the text so far, increasing the model's likelihood to talk about new topics.
    pub presence_penalty: f32,

    /// Number between -2.0 and 2.0.
    /// Positive values penalize new tokens based on their existing frequency in the text so far,
    /// decreasing the model's likelihood to repeat the same line verbatim.
    pub frequency_penalty: f32,

    /// Generates `best_of` completions server-side and returns the
    /// "best" (the one with the lowest log probability per token). Results cannot be streamed.
    /// When used with n, best_of controls the number of candidate completions and n specifies
    /// how many to return – best_of must be greater than n.
    /// Note: Because this parameter generates many completions, it can quickly consume your token
    /// quota. Use carefully and ensure that you have reasonable settings for max_tokens and stop.
    pub best_of: u32,

    /// Modify the likelihood of specified tokens appearing in the completion.
    /// Accepts a json object that maps tokens (specified by their token ID in the GPT tokenizer)
    /// to an associated bias value from -100 to 100. You can use this tokenizer tool (which works
    /// for both GPT-2 and GPT-3) to convert text to token IDs. Mathematically,
    /// the bias is added to the logits generated by the model prior to sampling. The exact effect
    /// will vary per model, but values between -1 and 1 should decrease or increase likelihood
    /// of selection; values like -100 or 100 should result in a ban or exclusive selection
    /// of the relevant token.
    pub logit_bias: Option<HashMap<Cow<'a, str>, i32>>,

    /// A unique identifier representing your end-user, which will help OpenAI to monitor and detect abuse.
    pub user: Option<Cow<'a, str>>
}

impl Default for Completion<'_> {
    fn default() -> Self {
        Self {
            prompt: Some(Cow::Borrowed("<|endoftext|>")),
            suffix: None,
            max_tokens: 16,
            temperature: 1.,
            top_p: 1.,
            n: 1,
            stream: false,
            logprobs: None,
            echo: false,
            stop: None,
            presence_penalty: 0.,
            frequency_penalty: 0.,
            best_of: 1,
            logit_bias: Some(HashMap::new()),
            user: Some(Cow::Borrowed(""))
        }
    }
}

impl Endpoint for Completion<'_> {
    const ENDPOINT: &'static str = "https://api.openai.com/v1/engines/{}/completions";

    fn request(
        &self,
        auth_token: &str,
        engine_id: Option<&str>
    ) -> Request<Body> {
        let endpoint = Self::ENDPOINT.replace("{}", engine_id.unwrap());
        let serialized = serde_json::to_string(&self)
            .expect("Failed to serialize request");
        trace!("endpoint={}, serialized={}", endpoint, serialized);

        super::request::post!(endpoint, auth_token, serialized)
    }
}