Files
oak-gpui/crates/ai/src/ai.rs
T

314 lines
10 KiB
Rust

use anyhow::{anyhow, Result};
use assets::Assets;
use collections::HashMap;
use editor::Editor;
use futures::AsyncBufReadExt;
use futures::{io::BufReader, AsyncReadExt, Stream, StreamExt};
use gpui::executor::Background;
use gpui::{actions, AppContext, Task, ViewContext};
use isahc::prelude::*;
use isahc::{http::StatusCode, Request};
use serde::{Deserialize, Serialize};
use std::cell::RefCell;
use std::fs;
use std::rc::Rc;
use std::{io, sync::Arc};
use util::channel::{ReleaseChannel, RELEASE_CHANNEL};
use util::{ResultExt, TryFutureExt};
actions!(ai, [Assist]);
// Data types for chat completion requests
#[derive(Serialize)]
struct OpenAIRequest {
model: String,
messages: Vec<RequestMessage>,
stream: bool,
}
#[derive(Serialize, Deserialize, Debug, Eq, PartialEq)]
struct RequestMessage {
role: Role,
content: String,
}
#[derive(Serialize, Deserialize, Debug, Eq, PartialEq)]
struct ResponseMessage {
role: Option<Role>,
content: Option<String>,
}
#[derive(Serialize, Deserialize, Debug, Eq, PartialEq)]
#[serde(rename_all = "lowercase")]
enum Role {
User,
Assistant,
System,
}
#[derive(Deserialize, Debug)]
struct OpenAIResponseStreamEvent {
pub id: Option<String>,
pub object: String,
pub created: u32,
pub model: String,
pub choices: Vec<ChatChoiceDelta>,
pub usage: Option<Usage>,
}
#[derive(Deserialize, Debug)]
struct Usage {
pub prompt_tokens: u32,
pub completion_tokens: u32,
pub total_tokens: u32,
}
#[derive(Deserialize, Debug)]
struct ChatChoiceDelta {
pub index: u32,
pub delta: ResponseMessage,
pub finish_reason: Option<String>,
}
#[derive(Deserialize, Debug)]
struct OpenAIUsage {
prompt_tokens: u64,
completion_tokens: u64,
total_tokens: u64,
}
#[derive(Deserialize, Debug)]
struct OpenAIChoice {
text: String,
index: u32,
logprobs: Option<serde_json::Value>,
finish_reason: Option<String>,
}
pub fn init(cx: &mut AppContext) {
if *RELEASE_CHANNEL == ReleaseChannel::Stable {
return;
}
let assistant = Rc::new(Assistant::default());
cx.add_action({
let assistant = assistant.clone();
move |editor: &mut Editor, _: &Assist, cx: &mut ViewContext<Editor>| {
assistant.assist(editor, cx).log_err();
}
});
cx.capture_action({
let assistant = assistant.clone();
move |_: &mut Editor, _: &editor::Cancel, cx: &mut ViewContext<Editor>| {
if !assistant.cancel_last_assist(cx.view_id()) {
cx.propagate_action();
}
}
});
}
type CompletionId = usize;
#[derive(Default)]
struct Assistant(RefCell<AssistantState>);
#[derive(Default)]
struct AssistantState {
assist_stacks: HashMap<usize, Vec<(CompletionId, Task<Option<()>>)>>,
next_completion_id: CompletionId,
}
impl Assistant {
fn assist(self: &Rc<Self>, editor: &mut Editor, cx: &mut ViewContext<Editor>) -> Result<()> {
let api_key = std::env::var("OPENAI_API_KEY")?;
let selections = editor.selections.all(cx);
let (user_message, insertion_site) = editor.buffer().update(cx, |buffer, cx| {
// Insert markers around selected text as described in the system prompt above.
let snapshot = buffer.snapshot(cx);
let mut user_message = String::new();
let mut user_message_suffix = String::new();
let mut buffer_offset = 0;
for selection in selections {
if !selection.is_empty() {
if user_message_suffix.is_empty() {
user_message_suffix.push_str("\n\n");
}
user_message_suffix.push_str("[Selected excerpt from above]\n");
user_message_suffix
.extend(snapshot.text_for_range(selection.start..selection.end));
user_message_suffix.push_str("\n\n");
}
user_message.extend(snapshot.text_for_range(buffer_offset..selection.start));
user_message.push_str("[SELECTION_START]");
user_message.extend(snapshot.text_for_range(selection.start..selection.end));
buffer_offset = selection.end;
user_message.push_str("[SELECTION_END]");
}
if buffer_offset < snapshot.len() {
user_message.extend(snapshot.text_for_range(buffer_offset..snapshot.len()));
}
user_message.push_str(&user_message_suffix);
// Ensure the document ends with 4 trailing newlines.
let trailing_newline_count = snapshot
.reversed_chars_at(snapshot.len())
.take_while(|c| *c == '\n')
.take(4);
let buffer_suffix = "\n".repeat(4 - trailing_newline_count.count());
buffer.edit([(snapshot.len()..snapshot.len(), buffer_suffix)], None, cx);
let snapshot = buffer.snapshot(cx); // Take a new snapshot after editing.
let insertion_site = snapshot.anchor_after(snapshot.len() - 2);
(user_message, insertion_site)
});
let this = self.clone();
let buffer = editor.buffer().clone();
let executor = cx.background_executor().clone();
let editor_id = cx.view_id();
let assist_id = util::post_inc(&mut self.0.borrow_mut().next_completion_id);
let assist_task = cx.spawn(|_, mut cx| {
async move {
// TODO: We should have a get_string method on assets. This is repateated elsewhere.
let content = Assets::get("contexts/system.zmd").unwrap();
let mut system_message = std::str::from_utf8(content.data.as_ref())
.unwrap()
.to_string();
if let Ok(custom_system_message_path) =
std::env::var("ZED_ASSISTANT_SYSTEM_PROMPT_PATH")
{
system_message.push_str(
"\n\nAlso consider the following user-defined system prompt:\n\n",
);
// TODO: Replace this with our file system trait object.
system_message.push_str(
&cx.background()
.spawn(async move { fs::read_to_string(custom_system_message_path) })
.await?,
);
}
let stream = stream_completion(
api_key,
executor,
OpenAIRequest {
model: "gpt-4".to_string(),
messages: vec![
RequestMessage {
role: Role::System,
content: system_message.to_string(),
},
RequestMessage {
role: Role::User,
content: user_message,
},
],
stream: false,
},
);
let mut messages = stream.await?;
while let Some(message) = messages.next().await {
let mut message = message?;
if let Some(choice) = message.choices.pop() {
buffer.update(&mut cx, |buffer, cx| {
let text: Arc<str> = choice.delta.content?.into();
buffer.edit([(insertion_site.clone()..insertion_site, text)], None, cx);
Some(())
});
}
}
this.0
.borrow_mut()
.assist_stacks
.get_mut(&editor_id)
.unwrap()
.retain(|(id, _)| *id != assist_id);
anyhow::Ok(())
}
.log_err()
});
self.0
.borrow_mut()
.assist_stacks
.entry(cx.view_id())
.or_default()
.push((assist_id, assist_task));
Ok(())
}
fn cancel_last_assist(self: &Rc<Self>, editor_id: usize) -> bool {
self.0
.borrow_mut()
.assist_stacks
.get_mut(&editor_id)
.and_then(|assists| assists.pop())
.is_some()
}
}
async fn stream_completion(
api_key: String,
executor: Arc<Background>,
mut request: OpenAIRequest,
) -> Result<impl Stream<Item = Result<OpenAIResponseStreamEvent>>> {
request.stream = true;
let (tx, rx) = futures::channel::mpsc::unbounded::<Result<OpenAIResponseStreamEvent>>();
let json_data = serde_json::to_string(&request)?;
let mut response = Request::post("https://api.openai.com/v1/chat/completions")
.header("Content-Type", "application/json")
.header("Authorization", format!("Bearer {}", api_key))
.body(json_data)?
.send_async()
.await?;
let status = response.status();
if status == StatusCode::OK {
executor
.spawn(async move {
let mut lines = BufReader::new(response.body_mut()).lines();
fn parse_line(
line: Result<String, io::Error>,
) -> Result<Option<OpenAIResponseStreamEvent>> {
if let Some(data) = line?.strip_prefix("data: ") {
let event = serde_json::from_str(&data)?;
Ok(Some(event))
} else {
Ok(None)
}
}
while let Some(line) = lines.next().await {
if let Some(event) = parse_line(line).transpose() {
tx.unbounded_send(event).log_err();
}
}
anyhow::Ok(())
})
.detach();
Ok(rx)
} else {
let mut body = String::new();
response.body_mut().read_to_string(&mut body).await?;
Err(anyhow!(
"Failed to connect to OpenAI API: {} {}",
response.status(),
body,
))
}
}