From 9fa09de8dff547f37c5526acdd84af32bde3260a Mon Sep 17 00:00:00 2001
From: Matteo Settenvini <matteo.settenvini@montecristosoftware.eu>
Date: Sun, 2 Jul 2023 02:06:27 +0200
Subject: [PATCH] Serve both files and directories

---
 README.md                 | 24 ++++++++++++-
 src/main.rs               | 71 ++++++++++++++++++++-------------------
 templates/index.html.tera |  2 +-
 3 files changed, 61 insertions(+), 36 deletions(-)

diff --git a/README.md b/README.md
index 45b6c87..6383b10 100644
--- a/README.md
+++ b/README.md
@@ -29,9 +29,31 @@ Then just configure Apache or NGINX to proxy to the given port. For example:
 
     # ... other options ...
 </VirtualHost>
-
 ```
 
+You probably also want a systemd unit file, for instance `/etc/systemd/system/serves3@.service`:
+
+```ini
+[Unit]
+Description=ServeS3, a S3 proxy
+StartLimitInterval=100
+StartLimitBurst=10
+
+[Service]
+Type=simple
+ExecStart=/usr/local/bin/serves3
+WorkingDirectory=/etc/serves3/%i/
+Environment=ROCKET_PORT=%i
+
+Restart=always
+RestartSec=5s
+
+[Install]
+WantedBy=multi-user.target
+```
+
+Then, e.g. for running on port 8000, you would put the corresponding configuration file in `/etc/serves3/8000/` and install the unit with `systemctl enable --now servers3@8000.service`.
+
 ## Build and install
 
 ```bash
diff --git a/src/main.rs b/src/main.rs
index b6bad3a..f3e74ea 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,8 +1,6 @@
 // SPDX-FileCopyrightText: © Matteo Settenvini <matteo.settenvini@montecristosoftware.eu>
 // SPDX-License-Identifier: EUPL-1.2
 
-use s3::serde_types::ListBucketResult;
-
 use {
     lazy_static::lazy_static,
     rocket::response::Responder,
@@ -80,61 +78,61 @@ enum Error {
 
 #[rocket::get("/<path..>")]
 async fn index(path: PathBuf) -> Result<FileView, Error> {
-    let parent = path.parent();
-
-    let s3_path = format!(
-        "{}{}",
-        path.display(),
-        match parent {
-            Some(_) => "/",
-            None => "",
-        }
-    );
-
     /*
        The way things work in S3, the following holds for us:
        - we need to use a slash as separator
        - folders need to be queried ending with a slash
+       - getting the bucket address will return an XML file
+         with all properties; we don't want that.
 
-       We try first to retrieve list an object as a folder. If we fail,
-       we fallback to retrieving the object itself.
+       We try first to retrieve list an object as a file. If we fail,
+       we fallback to retrieving the equivalent folder.
     */
-    let s3_objects = BUCKET.list(s3_path, Some("/".into())).await;
 
-    let s3_objects = match s3_objects {
-        Ok(s3_objects) => s3_objects,
-        Err(_) => {
-            // TODO: this can be big, we should use streaming,
-            // not loading in memory.
-            let data = BUCKET
-                .get_object(format!("{}", path.display()))
-                .await
-                .map_err(|_| Error::NotFound("Object not found".into()))?
-                .bytes()
-                .to_vec();
-            return Ok(FileView::File(data));
+    // FIXME: this can be big, we should use streaming,
+    // not loading in memory!
+    if !path.as_os_str().is_empty() {
+        let data = BUCKET
+            .get_object(format!("{}", path.display()))
+            .await
+            .map_err(|_| Error::NotFound("Object not found".into()));
+
+        if let Ok(contents) = data {
+            let bytes = contents.bytes().to_vec();
+            return Ok(FileView::File(bytes));
         }
-    };
+    }
 
-    let objects = s3_fileview(&s3_objects);
+    let objects = s3_fileview(&path).await?;
     let rendered = Template::render(
         "index",
         context! {
             path: format!("{}/", path.display()),
-            has_parent: !path.as_os_str().is_empty(),
             objects
         },
     );
     Ok(FileView::Folder(rendered))
 }
 
-fn s3_fileview(s3_objects: &Vec<ListBucketResult>) -> Vec<&str> {
+async fn s3_fileview(path: &PathBuf) -> Result<Vec<String>, Error> {
     /*
         if listing a folder:
         - folders will be under 'common_prefixes'
         - files will be under the 'contents' property
     */
-    s3_objects
+
+    let parent = path.parent();
+    let s3_folder_path = match parent {
+        Some(_) => format!("{}/", path.display()),
+        None => "".into(),
+    };
+
+    let s3_objects = BUCKET
+        .list(s3_folder_path, Some("/".into()))
+        .await
+        .map_err(|_| Error::NotFound("Object not found".into()))?;
+
+    let objects = s3_objects
         .iter()
         .flat_map(|list| -> Vec<Option<&str>> {
             let prefix = if let Some(p) = &list.prefix {
@@ -148,14 +146,19 @@ fn s3_fileview(s3_objects: &Vec<ListBucketResult>) -> Vec<&str> {
                 .iter()
                 .flatten()
                 .map(|dir| dir.prefix.strip_prefix(&prefix));
+
             let files = list
                 .contents
                 .iter()
                 .map(|obj| obj.key.strip_prefix(&prefix));
+
             folders.chain(files).collect()
         })
         .flatten()
-        .collect()
+        .map(str::to_owned)
+        .collect();
+
+    Ok(objects)
 }
 
 #[rocket::launch]
diff --git a/templates/index.html.tera b/templates/index.html.tera
index e702c72..5a83df0 100644
--- a/templates/index.html.tera
+++ b/templates/index.html.tera
@@ -8,7 +8,7 @@
     <body>
         <h1>{{ path }}</h1>
         <ul>
-            {% if has_parent %}
+            {% if path != "/" %}
             <li><a href="../">..</a></li>
             {% endif %}