lemmy/crates/routes/src/images.rs

240 lines
6.4 KiB
Rust

use actix_http::header::{HeaderName, ACCEPT_ENCODING, HOST};
use actix_web::{body::BodyStream, http::StatusCode, web::Data, *};
use anyhow::anyhow;
use futures::stream::{Stream, StreamExt};
use lemmy_utils::{claims::Claims, rate_limit::RateLimit, LemmyError};
use lemmy_websocket::LemmyContext;
use reqwest::Body;
use reqwest_middleware::{ClientWithMiddleware, RequestBuilder};
use serde::{Deserialize, Serialize};
use std::time::Duration;
pub fn config(cfg: &mut web::ServiceConfig, client: ClientWithMiddleware, rate_limit: &RateLimit) {
cfg
.app_data(Data::new(client))
.service(
web::resource("/pictrs/image")
.wrap(rate_limit.image())
.route(web::post().to(upload)),
)
// This has optional query params: /image/{filename}?format=jpg&thumbnail=256
.service(web::resource("/pictrs/image/{filename}").route(web::get().to(full_res)))
.service(web::resource("/pictrs/image/delete/{token}/{filename}").route(web::get().to(delete)));
}
#[derive(Debug, Serialize, Deserialize)]
struct Image {
file: String,
delete_token: String,
}
#[derive(Debug, Serialize, Deserialize)]
struct Images {
msg: String,
files: Option<Vec<Image>>,
}
#[derive(Deserialize)]
struct PictrsParams {
format: Option<String>,
thumbnail: Option<String>,
}
fn adapt_request(
request: &HttpRequest,
client: &ClientWithMiddleware,
url: String,
) -> RequestBuilder {
// remove accept-encoding header so that pictrs doesnt compress the response
const INVALID_HEADERS: &[HeaderName] = &[ACCEPT_ENCODING, HOST];
let client_request = client
.request(request.method().clone(), url)
.timeout(Duration::from_secs(30));
request
.headers()
.iter()
.fold(client_request, |client_req, (key, value)| {
if INVALID_HEADERS.contains(key) {
client_req
} else {
client_req.header(key, value)
}
})
}
async fn upload(
req: HttpRequest,
body: web::Payload,
client: web::Data<ClientWithMiddleware>,
context: web::Data<LemmyContext>,
) -> Result<HttpResponse, Error> {
// TODO: check rate limit here
let jwt = req
.cookie("jwt")
.expect("No auth header for picture upload");
if Claims::decode(jwt.value(), &context.secret().jwt_secret).is_err() {
return Ok(HttpResponse::Unauthorized().finish());
};
let image_url = format!("{}/image", pictrs_url(context.settings().pictrs_url)?);
let mut client_req = adapt_request(&req, &client, image_url);
if let Some(addr) = req.head().peer_addr {
client_req = client_req.header("X-Forwarded-For", addr.to_string())
};
let res = client_req
.body(Body::wrap_stream(make_send(body)))
.send()
.await
.map_err(error::ErrorBadRequest)?;
let status = res.status();
let images = res.json::<Images>().await.map_err(error::ErrorBadRequest)?;
Ok(HttpResponse::build(status).json(images))
}
async fn full_res(
filename: web::Path<String>,
web::Query(params): web::Query<PictrsParams>,
req: HttpRequest,
client: web::Data<ClientWithMiddleware>,
context: web::Data<LemmyContext>,
) -> Result<HttpResponse, Error> {
let name = &filename.into_inner();
// If there are no query params, the URL is original
let pictrs_url_settings = context.settings().pictrs_url;
let url = if params.format.is_none() && params.thumbnail.is_none() {
format!(
"{}/image/original/{}",
pictrs_url(pictrs_url_settings)?,
name,
)
} else {
// Use jpg as a default when none is given
let format = params.format.unwrap_or_else(|| "jpg".to_string());
let mut url = format!(
"{}/image/process.{}?src={}",
pictrs_url(pictrs_url_settings)?,
format,
name,
);
if let Some(size) = params.thumbnail {
url = format!("{}&thumbnail={}", url, size,);
}
url
};
image(url, req, client).await
}
async fn image(
url: String,
req: HttpRequest,
client: web::Data<ClientWithMiddleware>,
) -> Result<HttpResponse, Error> {
let mut client_req = adapt_request(&req, &client, url);
if let Some(addr) = req.head().peer_addr {
client_req = client_req.header("X-Forwarded-For", addr.to_string());
}
if let Some(addr) = req.head().peer_addr {
client_req = client_req.header("X-Forwarded-For", addr.to_string());
}
let res = client_req.send().await.map_err(error::ErrorBadRequest)?;
if res.status() == StatusCode::NOT_FOUND {
return Ok(HttpResponse::NotFound().finish());
}
let mut client_res = HttpResponse::build(res.status());
for (name, value) in res.headers().iter().filter(|(h, _)| *h != "connection") {
client_res.insert_header((name.clone(), value.clone()));
}
Ok(client_res.body(BodyStream::new(res.bytes_stream())))
}
async fn delete(
components: web::Path<(String, String)>,
req: HttpRequest,
client: web::Data<ClientWithMiddleware>,
context: web::Data<LemmyContext>,
) -> Result<HttpResponse, Error> {
let (token, file) = components.into_inner();
let url = format!(
"{}/image/delete/{}/{}",
pictrs_url(context.settings().pictrs_url)?,
&token,
&file
);
let mut client_req = adapt_request(&req, &client, url);
if let Some(addr) = req.head().peer_addr {
client_req = client_req.header("X-Forwarded-For", addr.to_string());
}
let res = client_req.send().await.map_err(error::ErrorBadRequest)?;
Ok(HttpResponse::build(res.status()).body(BodyStream::new(res.bytes_stream())))
}
fn pictrs_url(pictrs_url: Option<String>) -> Result<String, LemmyError> {
pictrs_url.ok_or_else(|| anyhow!("images_disabled").into())
}
fn make_send<S>(mut stream: S) -> impl Stream<Item = S::Item> + Send + Unpin + 'static
where
S: Stream + Unpin + 'static,
S::Item: Send,
{
// NOTE: the 8 here is arbitrary
let (tx, rx) = tokio::sync::mpsc::channel(8);
// NOTE: spawning stream into a new task can potentially hit this bug:
// - https://github.com/actix/actix-web/issues/1679
//
// Since 4.0.0-beta.2 this issue is incredibly less frequent. I have not personally reproduced it.
// That said, it is still technically possible to encounter.
actix_web::rt::spawn(async move {
while let Some(res) = stream.next().await {
if tx.send(res).await.is_err() {
break;
}
}
});
SendStream { rx }
}
struct SendStream<T> {
rx: tokio::sync::mpsc::Receiver<T>,
}
impl<T> Stream for SendStream<T>
where
T: Send,
{
type Item = T;
fn poll_next(
mut self: std::pin::Pin<&mut Self>,
cx: &mut std::task::Context<'_>,
) -> std::task::Poll<Option<Self::Item>> {
std::pin::Pin::new(&mut self.rx).poll_recv(cx)
}
}