3 files changed, 66 insertions, 6 deletions

diff --git a/server/Cargo.toml b/server/Cargo.toml
index 6118240..6648b80 100644
--- a/server/Cargo.toml
+++ b/server/Cargo.toml
@@ -22,6 +22,7 @@ base64 = "0.21.2"
 chrono = { version = "0.4.26", features = ["serde"] }
 
 argon2 = "0.5.1"
+sha2 = "0.10.7"
 aes-gcm-siv = "0.11.1"
 
 async-std = "1.12.0"
diff --git a/server/src/import.rs b/server/src/import.rs
index 2cd1998..a059694 100644
--- a/server/src/import.rs
+++ b/server/src/import.rs
@@ -6,10 +6,13 @@
 use crate::{database::Database, federation::Federation, CONF};
 use anyhow::{anyhow, bail, Context, Ok};
 use async_recursion::async_recursion;
+use base64::Engine;
 use jellyclient::Session;
-use jellycommon::{MediaSource, Node, NodePrivate, RemoteImportOptions};
+use jellycommon::{AssetLocation, MediaSource, Node, NodePrivate, RemoteImportOptions};
 use log::{error, info};
-use std::{ffi::OsStr, fs::File, os::unix::prelude::OsStrExt, path::PathBuf, sync::LazyLock};
+use std::{
+    ffi::OsStr, fs::File, os::unix::prelude::OsStrExt, path::PathBuf, str::FromStr, sync::LazyLock,
+};
 use tokio::sync::Semaphore;
 
 static IMPORT_SEM: LazyLock<Semaphore> = LazyLock::new(|| Semaphore::new(1));
@@ -125,11 +128,15 @@ async fn import_remote(
         .node(&opts.id)
         .await
         .context("fetching remote node")?;
+
+    let poster = cache_federation_asset(session, &opts.id, "poster").await?;
+    let backdrop = cache_federation_asset(session, &opts.id, "backdrop").await?;
+
     let mut node = Node {
         public: node,
         private: NodePrivate {
-            backdrop: None,
-            poster: None,
+            backdrop: Some(AssetLocation::Cache(backdrop)),
+            poster: Some(AssetLocation::Cache(poster)),
             import: None,
             source: Some(MediaSource::Remote {
                 host: opts.host.clone(),
@@ -160,3 +167,36 @@ async fn import_remote(
 
     Ok(())
 }
+
+async fn cache_federation_asset(
+    session: &Session,
+    identifier: &String,
+    role: &str,
+) -> anyhow::Result<PathBuf> {
+    let (poster, download) = cache_file(&["federation-asset", role, identifier]);
+    if let Some(d) = download {
+        session.node_asset(&identifier, role, d).await?;
+    }
+    Ok(poster)
+}
+
+fn cache_file(seed: &[&str]) -> (PathBuf, Option<File>) {
+    use sha2::Digest;
+    let mut d = sha2::Sha512::new();
+    for s in seed {
+        d.update(s.as_bytes());
+        d.update(b"\0");
+    }
+    let d = d.finalize();
+    let fname = base64::engine::general_purpose::URL_SAFE.encode(d);
+    let fname = &fname[..22]; // about 128 bits
+    let fullpath = CONF.cache_path.join(fname);
+    let cachepath = PathBuf::from_str(fname).unwrap();
+
+    let f = if !fullpath.exists() {
+        Some(File::create(&fullpath).unwrap())
+    } else {
+        None
+    };
+    (cachepath, f)
+}
diff --git a/server/src/routes/ui/assets.rs b/server/src/routes/ui/assets.rs
index 7fa083c..4b5c64a 100644
--- a/server/src/routes/ui/assets.rs
+++ b/server/src/routes/ui/assets.rs
@@ -9,6 +9,7 @@ use crate::{
     CONF,
 };
 use anyhow::anyhow;
+use jellycommon::AssetLocation;
 use log::info;
 use rocket::{get, http::ContentType, FromFormField, State, UriDisplayQuery};
 use std::{path::PathBuf, str::FromStr};
@@ -16,7 +17,9 @@ use tokio::fs::File;
 
 #[derive(FromFormField, UriDisplayQuery)]
 pub enum AssetRole {
+    #[field(value = "poster")]
     Poster,
+    #[field(value = "backdrop")]
     Backdrop,
 }
 
@@ -32,15 +35,31 @@ pub async fn r_item_assets(
         AssetRole::Backdrop => node.private.backdrop,
         AssetRole::Poster => node.private.poster,
     }
-    .map(|e| CONF.library_path.join(e))
+    .map(|e| e.path())
     .unwrap_or_else(|| {
         CONF.asset_path
             .join(PathBuf::from_str("fallback.jpeg").unwrap())
     });
     info!("loading asset from {path:?}");
-    let ext = path.extension().unwrap().to_str().unwrap();
+    let ext = path
+        .extension()
+        .map(|e| e.to_str().unwrap())
+        .unwrap_or("jpeg");
     Ok((
         ContentType::from_extension(ext).unwrap(),
         CacheControlFile::new(File::open(path).await?).await,
     ))
 }
+
+pub trait AssetLocationExt {
+    fn path(&self) -> PathBuf;
+}
+impl AssetLocationExt for AssetLocation {
+    fn path(&self) -> PathBuf {
+        match self {
+            AssetLocation::Assets(p) => CONF.asset_path.join(p),
+            AssetLocation::Cache(p) => CONF.cache_path.join(p),
+            AssetLocation::Library(p) => CONF.library_path.join(p),
+        }
+    }
+}