Merge pull request #58 from LemmyNet/forward-backend-requests

Forward backend requests

docker/nginx.conf

@@ -57,16 +57,7 @@ server {
 
     # lemmybb frontend
     location / {
-        set $proxpass "http://0.0.0.0:8701";
-        # federation requests go to backend
-        if ($http_accept ~ "^application/.*$") {
-            set $proxpass "http://0.0.0.0:8703";
-        }
-        # fonts have similar accept header but need to be handled by frontend
-        if ($http_accept ~ "^application/font.*$") {
-            set $proxpass "http://0.0.0.0:8701";
-        }
-        proxy_pass $proxpass;
+        proxy_pass "http://0.0.0.0:8701";
         rewrite ^(.+)/+$ $1 permanent;
     }
 

src/main.rs

@@ -20,9 +20,9 @@ use crate::{
     routes::{
         comment::*,
         community::*,
+        federation::*,
         post::*,
         private_message::*,
-        redirects::*,
         site::*,
         user::*,
     },
@@ -106,15 +106,16 @@ fn init_rocket() -> Result<Rocket<Build>, Error> {
                 private_message_editor,
                 do_send_private_message,
                 image,
-                redirect_apub_community,
-                redirect_apub_user,
-                redirect_apub_post,
-                redirect_apub_comment,
+                apub_community,
+                apub_user,
+                apub_post,
+                apub_comment,
                 report,
                 do_report,
                 edit_profile,
                 do_edit_profile,
-                community_list
+                community_list,
+                inboxes
             ],
         )
         .mount("/assets", FileServer::from(relative!("assets"))))

src/routes/federation.rs

@@ -0,0 +1,138 @@
+use crate::{
+    api::{comment::get_comment, community::get_community, user::get_person, NameOrId, CLIENT},
+    env::lemmy_backend,
+    error::ErrorPage,
+    rocket_uri_macro_view_forum,
+    rocket_uri_macro_view_profile,
+    rocket_uri_macro_view_topic,
+    routes::auth,
+};
+use anyhow::Error;
+use reqwest::header::{HeaderMap, HeaderName, HeaderValue};
+use rocket::{
+    http::CookieJar,
+    request::{FromRequest, Outcome},
+    response::Redirect,
+    Either,
+};
+use std::{path::PathBuf, str::FromStr};
+
+type ReturnType = Result<Either<Redirect, String>, ErrorPage>;
+
+#[get("/c/<name>")]
+pub async fn apub_community(
+    name: String,
+    accept: AcceptHeader,
+    cookies: &CookieJar<'_>,
+) -> ReturnType {
+    if accept.0.starts_with("application/") {
+        return foward_apub_fetch(format!("{}/c/{}", lemmy_backend(), name), accept).await;
+    }
+    let community = get_community(NameOrId::Name(name), auth(cookies)).await?;
+    let f = community.community_view.community.id.0;
+    Ok(Either::Left(Redirect::to(uri!(view_forum(
+        f,
+        Some(1),
+        Option::<String>::None
+    )))))
+}
+
+#[get("/u/<name>")]
+pub async fn apub_user(name: String, accept: AcceptHeader, cookies: &CookieJar<'_>) -> ReturnType {
+    if accept.0.starts_with("application/") {
+        return foward_apub_fetch(format!("{}/u/{}", lemmy_backend(), name), accept).await;
+    }
+    let user = get_person(NameOrId::Name(name), auth(cookies)).await?;
+    let u = user.person_view.person.id.0;
+    Ok(Either::Left(Redirect::to(uri!(view_profile(u)))))
+}
+
+#[get("/post/<id>")]
+pub async fn apub_post(id: i32, accept: AcceptHeader) -> ReturnType {
+    if accept.0.starts_with("application/") {
+        return foward_apub_fetch(format!("{}/post/{}", lemmy_backend(), id), accept).await;
+    }
+    Ok(Either::Left(Redirect::to(uri!(view_topic(id, Some(1))))))
+}
+
+#[get("/comment/<t>")]
+pub async fn apub_comment(t: i32, accept: AcceptHeader, cookies: &CookieJar<'_>) -> ReturnType {
+    if accept.0.starts_with("application/") {
+        return foward_apub_fetch(format!("{}/comment/{}", lemmy_backend(), t), accept).await;
+    }
+    let comment = get_comment(t, auth(cookies)).await?;
+    // TODO: figure out actual page
+    Ok(Either::Left(Redirect::to(format!(
+        "/view_topic?t={}&page=1#p{}",
+        t, comment.comment_view.comment.id
+    ))))
+}
+
+/// In case an activitypub object is being fetched, forward request to Lemmy backend
+async fn foward_apub_fetch(url: String, accept: AcceptHeader) -> ReturnType {
+    let res = CLIENT
+        .get(url)
+        .header("accept", accept.0)
+        .send()
+        .await?
+        .text()
+        .await?;
+    Ok(Either::Right(res))
+}
+
+#[post("/<path..>", data = "<body>")]
+pub async fn inboxes(
+    path: PathBuf,
+    body: String,
+    headers: Headers<'_>,
+) -> Result<String, ErrorPage> {
+    let url = format!("{}/{}", lemmy_backend(), path.to_str().unwrap());
+    let headers = headers
+        .0
+        .iter()
+        .map(|h| {
+            Ok((
+                HeaderName::from_str(h.name.as_str())?,
+                HeaderValue::from_str(&h.value)?,
+            ))
+        })
+        .collect::<Result<HeaderMap, Error>>()?;
+
+    Ok(CLIENT
+        .post(url)
+        .headers(headers)
+        .body(body)
+        .send()
+        .await?
+        .text()
+        .await?)
+}
+
+// Retrieve request headers
+// https://github.com/SergioBenitez/Rocket/issues/178#issuecomment-953370904
+pub struct Headers<'r>(&'r rocket::http::HeaderMap<'r>);
+
+#[rocket::async_trait]
+impl<'r> FromRequest<'r> for Headers<'r> {
+    type Error = std::convert::Infallible;
+
+    async fn from_request(req: &'r rocket::Request<'_>) -> Outcome<Self, Self::Error> {
+        Outcome::Success(Headers(req.headers()))
+    }
+}
+
+pub struct AcceptHeader(String);
+
+#[rocket::async_trait]
+impl<'r> FromRequest<'r> for AcceptHeader {
+    type Error = std::convert::Infallible;
+
+    async fn from_request(req: &'r rocket::Request<'_>) -> Outcome<Self, Self::Error> {
+        Outcome::Success(AcceptHeader(
+            req.headers()
+                .get_one("accept")
+                .unwrap_or_default()
+                .to_string(),
+        ))
+    }
+}

src/routes/mod.rs

@@ -1,8 +1,8 @@
 pub mod comment;
 pub mod community;
+pub mod federation;
 pub mod post;
 pub mod private_message;
-pub mod redirects;
 pub mod site;
 pub mod user;