activitypub-federation-rust/src/fetch/mod.rs
cetra3 c356265cf4
Remove actix-rt and replace with tokio tasks (#42)
* Remove `actix-rt` and replace with tokio tasks

* Include activity queue test

* Use older `Arc` method

* Refactor to not re-process PEM data on each request

* Add retry queue and spawn tokio tasks directly

* Fix doc error

* Remove semaphore and use join set for backpressure

* Fix debug issue with multiple mailboxes
2023-06-20 11:54:14 +02:00

77 lines
2.4 KiB
Rust

//! Utilities for fetching data from other servers
//!
#![doc = include_str!("../../docs/07_fetching_data.md")]
use crate::{
config::Data,
error::Error,
http_signatures::sign_request,
reqwest_shim::ResponseExt,
FEDERATION_CONTENT_TYPE,
};
use bytes::Bytes;
use http::StatusCode;
use serde::de::DeserializeOwned;
use std::sync::atomic::Ordering;
use tracing::info;
use url::Url;
/// Typed wrapper for collection IDs
pub mod collection_id;
/// Typed wrapper for Activitypub Object ID which helps with dereferencing and caching
pub mod object_id;
/// Resolves identifiers of the form `name@example.com`
pub mod webfinger;
/// Fetch a remote object over HTTP and convert to `Kind`.
///
/// [crate::fetch::object_id::ObjectId::dereference] wraps this function to add caching and
/// conversion to database type. Only use this function directly in exceptional cases where that
/// behaviour is undesired.
///
/// Every time an object is fetched via HTTP, [RequestData.request_counter] is incremented by one.
/// If the value exceeds [FederationSettings.http_fetch_limit], the request is aborted with
/// [Error::RequestLimit]. This prevents denial of service attacks where an attack triggers
/// infinite, recursive fetching of data.
pub async fn fetch_object_http<T: Clone, Kind: DeserializeOwned>(
url: &Url,
data: &Data<T>,
) -> Result<Kind, Error> {
let config = &data.config;
// dont fetch local objects this way
debug_assert!(url.domain() != Some(&config.domain));
config.verify_url_valid(url).await?;
info!("Fetching remote object {}", url.to_string());
let counter = data.request_counter.fetch_add(1, Ordering::SeqCst);
if counter > config.http_fetch_limit {
return Err(Error::RequestLimit);
}
let req = config
.client
.get(url.as_str())
.header("Accept", FEDERATION_CONTENT_TYPE)
.timeout(config.request_timeout);
let res = if let Some((actor_id, private_key_pem)) = config.signed_fetch_actor.as_deref() {
let req = sign_request(
req,
actor_id,
Bytes::new(),
private_key_pem.clone(),
data.config.http_signature_compat,
)
.await?;
config.client.execute(req).await.map_err(Error::other)?
} else {
req.send().await.map_err(Error::other)?
};
if res.status() == StatusCode::GONE {
return Err(Error::ObjectDeleted);
}
res.json_limited().await
}