chore: update dependencies to latest versions

Reviewed-on: matteo/serves3#3

.gitignore

@@ -7,4 +7,4 @@
 
 /build
 /target
-/Settings.toml
+/serves3.toml

.pre-commit-config.yaml

@@ -3,7 +3,7 @@
 
 repos:
 - repo: https://github.com/pre-commit/pre-commit-hooks
-  rev: v4.5.0
+  rev: v4.6.0
   hooks:
   - id: check-yaml
     name: Check YAML files syntax
@@ -23,7 +23,7 @@ repos:
     name: Ensure no trailing spaces at the end of lines
 
 - repo: https://github.com/Lucas-C/pre-commit-hooks.git
-  rev: v1.5.2
+  rev: v1.5.5
   hooks:
   - id: remove-crlf
     name: Enforce LF instead of CRLF for newlines
@@ -40,7 +40,7 @@ repos:
     name: Check Rust code
 
 - repo: https://github.com/fsfe/reuse-tool.git
-  rev: v2.1.0
+  rev: v4.0.3
   hooks:
   - id: reuse
     name: Check copyright and license information
@@ -56,6 +56,6 @@ repos:
     - id: trufflehog
       name: TruffleHog
       description: Detect secrets in your data.
-      entry: bash -c 'podman run -v "$(pwd):/workdir" --rm docker.io/trufflesecurity/trufflehog:latest git file:///workdir'
+      entry: bash -c 'podman run -v "$(pwd):/workdir" --rm docker.io/trufflesecurity/trufflehog:latest git file:///workdir' --only-verified
       language: system
       stages: ["commit", "push"]

.vscode/launch.json

@@ -42,6 +42,25 @@
             },
             "args": [],
             "cwd": "${workspaceFolder}"
+        },
+        {
+            "type": "lldb",
+            "request": "launch",
+            "name": "Debug integration test 'integration'",
+            "cargo": {
+                "args": [
+                    "test",
+                    "--no-run",
+                    "--test=integration",
+                    "--package=serves3"
+                ],
+                "filter": {
+                    "name": "integration",
+                    "kind": "test"
+                }
+            },
+            "args": [],
+            "cwd": "${workspaceFolder}"
         }
     ]
 }

.vscode/settings.json

@@ -2,4 +2,5 @@
 // SPDX-License-Identifier: CC0-1.0
 {
     "liveServer.settings.port": 8001,
+    "cmake.configureOnOpen": true,
 }

CMakeLists.txt

@@ -3,13 +3,15 @@
 
 cmake_minimum_required(VERSION 3.25)
 
-project(serves3 VERSION 1.0.0 LANGUAGES NONE)
+project(serves3 VERSION 1.1.0 LANGUAGES C)
+
+include(GNUInstallDirs)
 
 include(FetchContent)
 FetchContent_Declare(
     Corrosion
     GIT_REPOSITORY https://github.com/corrosion-rs/corrosion.git
-    GIT_TAG v0.4.1
+    GIT_TAG v0.5.0
 )
 FetchContent_MakeAvailable(Corrosion)
 
@@ -20,3 +22,7 @@ corrosion_import_crate(
 message(STATUS "Imported crates: ${imported_crates}")
 
 install(IMPORTED_RUNTIME_ARTIFACTS serves3)
+install(FILES serves3.toml.example
+  DESTINATION ${CMAKE_INSTALL_DOCDIR})
+install(FILES serves3@.service
+  DESTINATION ${CMAKE_INSTALL_PREFIX}/lib/systemd/system)

Cargo.toml

@@ -3,7 +3,7 @@
 
 [package]
 name = "serves3"
-version = "1.0.0"
+version = "1.1.1"
 
 authors = ["Matteo Settenvini <matteo.settenvini@montecristosoftware.eu>"]
 description = "A very simple proxy to browse files from private S3 buckets"
@@ -20,11 +20,27 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-config = "0.13"
+anyhow = "1.0"
 human-size = "0.4"
 lazy_static = "1.4"
+log = "0.4"
 rocket = "0.5"
-rocket_dyn_templates = { version = "0.1.0", features = ["tera"] }
+rocket_dyn_templates = { version = "0.2.0", features = ["tera"] }
-rust-s3 = { version = "0.33", default-features = false, features = ["tokio-native-tls"] }
+rust-s3 = { version = "0.35", default-features = false, features = [
-serde = { version = "1.0" }
+    "tokio-rustls-tls",
-tempfile = { version = "3.6" }
+] }
+serde = "1.0"
+tempfile = "3.6"
+
+[dev-dependencies]
+delegate = "0.13"
+futures = "0.3"
+libc = "0.2"
+regex = "1.10"
+reqwest = "0.12"
+rstest = "0.22"
+scraper = "0.20"
+test-log = "0.2"
+testcontainers = "0.23"
+testcontainers-modules = { version = "0.11", features = ["minio"] }
+tokio = { version = "1", features = ["process"] }

README.md

@@ -1,5 +1,8 @@
-[//]: # SPDX-FileCopyrightText: © Matteo Settenvini <matteo.settenvini@montecristosoftware.eu>
+
-[//]: # SPDX-License-Identifier: EUPL-1.2
+<!--
+    SPDX-FileCopyrightText: © Matteo Settenvini <matteo.settenvini@montecristosoftware.eu>
+    SPDX-License-Identifier: EUPL-1.2
+-->
 
 # serves3
 
@@ -11,9 +14,39 @@ Also helpful to do a different TLS termination.
 
 ## Configuration
 
-Copy `Settings.toml.example` to `Settings.toml` and adjust your settings.
+Copy `serves3.toml.example` to `serves3.toml` from this project's sources and adjust your settings. If the project was built and installed via CMake, a copy of the example settings file is in `/usr/share/doc/serves3`.
 
-You can also add a `Rocket.toml` file to customize the server options. See the [Rocket documentation](https://rocket.rs/v0.5-rc/guide/configuration/#rockettoml).
+For instance:
+
+```toml
+# apply this configuration to Rocket's "default" profile
+[default.s3_bucket]
+
+# the bucket name
+name = ""
+ # the API endpoint address
+endpoint = "https://eu-central-1.linodeobjects.com"
+# the bucket region
+region = "eu-central-1"
+# the access key ID
+access_key_id = ""
+# the access key secret
+secret_access_key = ""
+# whether to use path_style S3 URLs, see
+# https://docs.aws.amazon.com/AmazonS3/latest/userguide/VirtualHosting.html#path-style-access
+path_style = false
+
+# Here you can add any other rocket options, see
+# https://rocket.rs/guide/v0.5/configuration/
+
+[default]
+
+[debug]
+
+[release]
+```
+
+You can also use the same file to customize the server options. See the [Rocket documentation](https://rocket.rs/v0.5-rc/guide/configuration/#rockettoml) for a list of understood values.
 
 Then just configure Apache or NGINX to proxy to the given port. For example:
 
@@ -59,10 +92,10 @@ Then, e.g. for running on port 8000, you would put the corresponding configurati
 If you want more granular control on installation options, use CMake:
 
 ```bash
-cmake -B build .
+cmake -DCMAKE_INSTALL_PREFIX=/usr -B build .
 cmake --build build
-cmake --install build
+sudo cmake --install build
-cd run-folder # folder with Settings.toml
+cd run-folder # folder with serves3.toml
 serves3
 ```
 
@@ -70,6 +103,17 @@ Else you can simply rely on `cargo`:
 
 ```bash
 cargo install --root /usr/local --path . # for instance
-cd run-folder # folder with Settings.toml
+cd run-folder # folder with serves3.toml
 serves3
 ```
+
+# Changelog
+
+## 1.1.0 Reworked configuration file logic
+
+* **Breaking change**: configuration file renamed to `serves3.toml`. Please note that the format changed slightly; have a look at the provided `serves3.toml.example` file for reference.
+* Fixes #2: URLs to directories not ending with a slash are not redirected properly
+
+## 1.0.0
+
+* Initial release.

Settings.toml.example

@@ -1,9 +0,0 @@
-# SPDX-FileCopyrightText: Public domain.
-# SPDX-License-Identifier: CC0-1.0
-
-access_key_id = ""
-secret_access_key = ""
-
-bucket = ""
-endpoint = "https://eu-central-1.linodeobjects.com"
-region = "eu-central-1"

deny.toml

@@ -12,6 +12,7 @@
 # The values provided in this template are the default values that will be used
 # when any section or field is not specified in your own configuration
 
+[graph]
 # If 1 or more target triples (and optionally, target_features) are specified,
 # only the specified targets will be checked when running `cargo deny check`.
 # This means, if a particular package is only ever used as a target specific
@@ -38,30 +39,13 @@ targets = [
 db-path = "~/.cargo/advisory-db"
 # The url(s) of the advisory databases to use
 db-urls = ["https://github.com/rustsec/advisory-db"]
-# The lint level for security vulnerabilities
-vulnerability = "deny"
-# The lint level for unmaintained crates
-unmaintained = "warn"
 # The lint level for crates that have been yanked from their source registry
 yanked = "warn"
-# The lint level for crates with security notices. Note that as of
-# 2019-12-17 there are no security notice advisories in
-# https://github.com/rustsec/advisory-db
-notice = "warn"
 # A list of advisory IDs to ignore. Note that ignored advisories will still
 # output a note when they are encountered.
 ignore = [
     #"RUSTSEC-0000-0000",
 ]
-# Threshold for security vulnerabilities, any vulnerability with a CVSS score
-# lower than the range specified will be ignored. Note that ignored advisories
-# will still output a note when they are encountered.
-# * None - CVSS Score 0.0
-# * Low - CVSS Score 0.1 - 3.9
-# * Medium - CVSS Score 4.0 - 6.9
-# * High - CVSS Score 7.0 - 8.9
-# * Critical - CVSS Score 9.0 - 10.0
-#severity-threshold =
 
 # If this is true, then cargo deny will use the git executable to fetch advisory database.
 # If this is false, then it uses a built-in git library.
@@ -73,36 +57,20 @@ ignore = [
 # More documentation for the licenses section can be found here:
 # https://embarkstudios.github.io/cargo-deny/checks/licenses/cfg.html
 [licenses]
-# The lint level for crates which do not have a detectable license
-unlicensed = "deny"
 # List of explicitly allowed licenses
 # See https://spdx.org/licenses/ for list of possible licenses
 # [possible values: any SPDX 3.11 short identifier (+ optional exception)].
 allow = [
-    #"MIT",
+    "Apache-2.0",
-    #"Apache-2.0",
+    "BSD-3-Clause",
-    #"Apache-2.0 WITH LLVM-exception",
+    "CC0-1.0",
+    "EUPL-1.2",
+    "ISC",
+    "MIT",
+    "OpenSSL",
+    "MPL-2.0",
+    "Unicode-DFS-2016",
 ]
-# List of explicitly disallowed licenses
-# See https://spdx.org/licenses/ for list of possible licenses
-# [possible values: any SPDX 3.11 short identifier (+ optional exception)].
-deny = [
-    #"Nokia",
-]
-# Lint level for licenses considered copyleft
-copyleft = "allow"
-# Blanket approval or denial for OSI-approved or FSF Free/Libre licenses
-# * both - The license will be approved if it is both OSI-approved *AND* FSF
-# * either - The license will be approved if it is either OSI-approved *OR* FSF
-# * osi-only - The license will be approved if is OSI-approved *AND NOT* FSF
-# * fsf-only - The license will be approved if is FSF *AND NOT* OSI-approved
-# * neither - This predicate is ignored and the default lint level is used
-allow-osi-fsf-free = "either"
-# Lint level used when no other predicates are matched
-# 1. License isn't in the allow or deny lists
-# 2. License isn't copyleft
-# 3. License isn't OSI/FSF, or allow-osi-fsf-free = "neither"
-default = "deny"
 # The confidence threshold for detecting a license from license text.
 # The higher the value, the more closely the license text must be to the
 # canonical license text of a valid SPDX license file.
@@ -133,7 +101,7 @@ expression = "MIT AND ISC AND OpenSSL"
 # depending on the rest of your configuration
 license-files = [
     # Each entry is a crate relative path, and the (opaque) hash of its contents
-    { path = "LICENSE", hash = 0xbd0eed23 }
+    { path = "LICENSE", hash = 0xbd0eed23 },
 ]
 
 [licenses.private]

serves3.toml.example

@@ -0,0 +1,28 @@
+# SPDX-FileCopyrightText: Public domain.
+# SPDX-License-Identifier: CC0-1.0
+
+# apply this configuration to Rocket's "default" profile
+[default.s3_bucket]
+
+# the bucket name
+name = ""
+ # the API endpoint address
+endpoint = "https://eu-central-1.linodeobjects.com"
+# the bucket region
+region = "eu-central-1"
+# the access key ID
+access_key_id = ""
+# the access key secret
+secret_access_key = ""
+# whether to use path_style S3 URLs, see
+# https://docs.aws.amazon.com/AmazonS3/latest/userguide/VirtualHosting.html#path-style-access
+path_style = false
+
+# Here you can add any other rocket options, see
+# https://rocket.rs/guide/v0.5/configuration/
+
+[default]
+
+[debug]
+
+[release]

serves3@.service

@@ -0,0 +1,19 @@
+# SPDX-FileCopyrightText: © Matteo Settenvini <matteo.settenvini@montecristosoftware.eu>
+# SPDX-License-Identifier: CC0-1.0
+
+[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

src/main.rs

@@ -1,72 +1,28 @@
 // SPDX-FileCopyrightText: © Matteo Settenvini <matteo.settenvini@montecristosoftware.eu>
 // SPDX-License-Identifier: EUPL-1.2
 
+mod settings;
+mod sizes;
+
 use {
+    anyhow::Result,
     lazy_static::lazy_static,
-    rocket::response::Responder,
+    rocket::{
-    rocket::serde::Serialize,
+        fairing::AdHoc,
+        figment::{
+            providers::{Env, Format as _, Toml},
+            Profile,
+        },
+        http::uri::Origin,
+        response::{Redirect, Responder},
+        serde::Serialize,
+        State,
+    },
     rocket_dyn_templates::{context, Template},
+    settings::Settings,
     std::path::PathBuf,
 };
 
-struct Settings {
-    access_key_id: String,
-    secret_access_key: String,
-    bucket_name: String,
-    endpoint: String,
-    region: String,
-}
-
-lazy_static! {
-    static ref SETTINGS: Settings = {
-        let settings = config::Config::builder()
-            .add_source(config::File::with_name("Settings.toml"))
-            .add_source(config::Environment::with_prefix("SERVES3"))
-            .build()
-            .unwrap();
-
-        Settings {
-            access_key_id: settings
-                .get_string("access_key_id")
-                .expect("Missing configuration key access_key_id"),
-            secret_access_key: settings
-                .get_string("secret_access_key")
-                .expect("Missing configuration key secret_access_key"),
-            bucket_name: settings
-                .get_string("bucket")
-                .expect("Missing configuration key bucket"),
-            region: settings
-                .get_string("region")
-                .expect("Missing configuration key region"),
-            endpoint: settings
-                .get_string("endpoint")
-                .expect("Missing configuration key endpoint"),
-        }
-    };
-    static ref BUCKET: s3::bucket::Bucket = {
-        let region = s3::Region::Custom {
-            region: SETTINGS.region.clone(),
-            endpoint: SETTINGS.endpoint.clone(),
-        };
-
-        let credentials = s3::creds::Credentials::new(
-            Some(&SETTINGS.access_key_id),
-            Some(&SETTINGS.secret_access_key),
-            None,
-            None,
-            None,
-        )
-        .expect("Wrong server S3 configuration");
-        s3::bucket::Bucket::new(&SETTINGS.bucket_name, region, credentials)
-            .expect("Cannot find or authenticate to S3 bucket")
-    };
-    static ref FILEVIEW_TEMPLATE: &'static str = std::include_str!("../templates/index.html.tera");
-
-    // Workaround for https://github.com/SergioBenitez/Rocket/issues/1792
-    static ref EMPTY_DIR: tempfile::TempDir = tempfile::tempdir()
-        .expect("Unable to create an empty temporary folder, is the whole FS read-only?");
-}
-
 #[derive(Responder)]
 enum FileView {
     #[response(content_type = "text/html")]
@@ -74,6 +30,8 @@ enum FileView {
 
     #[response(content_type = "application/octet-stream")]
     File(Vec<u8>),
+
+    Redirect(Redirect),
 }
 
 #[derive(Serialize)]
@@ -94,7 +52,11 @@ enum Error {
 }
 
 #[rocket::get("/<path..>")]
-async fn index(path: PathBuf) -> Result<FileView, Error> {
+async fn index(
+    path: PathBuf,
+    uri: &Origin<'_>,
+    state: &State<Settings>,
+) -> Result<FileView, Error> {
     /*
        The way things work in S3, the following holds for us:
        - we need to use a slash as separator
@@ -106,11 +68,18 @@ async fn index(path: PathBuf) -> Result<FileView, Error> {
        We try first to retrieve list an object as a file. If we fail,
        we fallback to retrieving the equivalent folder.
     */
-
+    if let Ok(result) = s3_serve_file(&path, &state).await {
-    if let Ok(result) = s3_serve_file(&path).await {
         Ok(result)
     } else {
-        let objects = s3_fileview(&path).await?;
+        // We need to redirect to a path ending with a slash as
+        // per comment above if we know this is not a file.
+        let mut uri = uri.to_string();
+        if !uri.ends_with('/') {
+            uri.push('/');
+            return Ok(FileView::Redirect(Redirect::permanent(uri)));
+        }
+
+        let objects = s3_fileview(&path, &state).await?;
         let rendered = Template::render(
             "index",
             context! {
@@ -122,7 +91,7 @@ async fn index(path: PathBuf) -> Result<FileView, Error> {
     }
 }
 
-async fn s3_serve_file(path: &PathBuf) -> Result<FileView, Error> {
+async fn s3_serve_file(path: &PathBuf, settings: &Settings) -> Result<FileView, Error> {
     let is_root_prefix = path.as_os_str().is_empty();
     if is_root_prefix {
         return Err(Error::NotFound("Root prefix is not a file".into()));
@@ -130,7 +99,8 @@ async fn s3_serve_file(path: &PathBuf) -> Result<FileView, Error> {
 
     // FIXME: this can be big, we should use streaming,
     // not loading in memory!
-    let response = BUCKET
+    let response = settings
+        .s3_bucket
         .get_object(format!("{}", path.display()))
         .await
         .map_err(|_| Error::UnknownError("Unable to connect to S3 bucket".into()))?;
@@ -145,7 +115,7 @@ async fn s3_serve_file(path: &PathBuf) -> Result<FileView, Error> {
     }
 }
 
-async fn s3_fileview(path: &PathBuf) -> Result<Vec<FileViewItem>, Error> {
+async fn s3_fileview(path: &PathBuf, settings: &Settings) -> Result<Vec<FileViewItem>, Error> {
     /*
         if listing a folder:
         - folders will be under 'common_prefixes'
@@ -158,7 +128,8 @@ async fn s3_fileview(path: &PathBuf) -> Result<Vec<FileViewItem>, Error> {
         None => "".into(),
     };
 
-    let s3_objects = BUCKET
+    let s3_objects = settings
+        .s3_bucket
         .list(s3_folder_path, Some("/".into()))
         .await
         .map_err(|_| Error::NotFound("Object not found".into()))?;
@@ -187,7 +158,7 @@ async fn s3_fileview(path: &PathBuf) -> Result<Vec<FileViewItem>, Error> {
                 path.map(|path| FileViewItem {
                     path: path.to_owned(),
                     size_bytes: obj.size,
-                    size: size_bytes_to_human(obj.size),
+                    size: sizes::bytes_to_human(obj.size),
                     last_modification: obj.last_modified.clone(),
                 })
             });
@@ -200,41 +171,27 @@ async fn s3_fileview(path: &PathBuf) -> Result<Vec<FileViewItem>, Error> {
     Ok(objects)
 }
 
-fn size_bytes_to_human(bytes: u64) -> String {
+lazy_static! {
-    use human_size::{Any, SpecificSize};
+    // Workaround for https://github.com/SergioBenitez/Rocket/issues/1792
-
+    static ref EMPTY_DIR: tempfile::TempDir = tempfile::tempdir()
-    let size: f64 = bytes as f64;
+        .expect("Unable to create an empty temporary folder, is the whole FS read-only?");
-    let digits = size.log10().floor() as u32;
-    let mut order = digits / 3;
-    let unit = match order {
-        0 => Any::Byte,
-        1 => Any::Kilobyte,
-        2 => Any::Megabyte,
-        _ => {
-            order = 3; // Let's stop here.
-            Any::Gigabyte
-        }
-    };
-
-    format!(
-        "{:.3}",
-        SpecificSize::new(size / 10u64.pow(order * 3) as f64, unit)
-            .unwrap_or(SpecificSize::new(0., Any::Byte).unwrap())
-    )
 }
 
 #[rocket::launch]
 fn rocket() -> _ {
-    eprintln!("Proxying to {} for {}", BUCKET.host(), BUCKET.name());
+    let config_figment = rocket::Config::figment()
-
+        .merge(Toml::file("serves3.toml").nested())
-    let config_figment = rocket::Config::figment().merge(("template_dir", EMPTY_DIR.path())); // We compile the templates in anyway.
+        .merge(Env::prefixed("SERVES3_").global())
+        .merge(("template_dir", EMPTY_DIR.path())) // We compile the templates in anyway
+        .select(Profile::from_env_or("SERVES3_PROFILE", "default"));
 
     rocket::custom(config_figment)
         .mount("/", rocket::routes![index])
+        .attach(AdHoc::config::<Settings>())
         .attach(Template::custom(|engines| {
             engines
                 .tera
-                .add_raw_template("index", *FILEVIEW_TEMPLATE)
+                .add_raw_template("index", std::include_str!("../templates/index.html.tera"))
                 .unwrap()
         }))
 }

src/settings.rs

@@ -0,0 +1,67 @@
+// SPDX-FileCopyrightText: © Matteo Settenvini <matteo.settenvini@montecristosoftware.eu>
+// SPDX-License-Identifier: EUPL-1.2
+
+use {anyhow::anyhow, rocket::serde::Deserialize, serde::de::Error};
+
+#[derive(Deserialize)]
+#[serde(crate = "rocket::serde")]
+pub struct Settings {
+    #[serde(deserialize_with = "deserialize_s3_bucket")]
+    pub s3_bucket: Box<s3::Bucket>,
+}
+
+fn deserialize_s3_bucket<'de, D>(deserializer: D) -> Result<Box<s3::Bucket>, D::Error>
+where
+    D: serde::Deserializer<'de>,
+{
+    let config = S3Config::deserialize(deserializer)?;
+    config.try_into().map_err(D::Error::custom)
+}
+
+#[derive(Deserialize)]
+pub struct S3Config {
+    pub name: String,
+    pub endpoint: String,
+    pub region: String,
+
+    #[serde(default)]
+    pub path_style: bool,
+
+    pub access_key_id: String,
+    pub secret_access_key: String,
+}
+
+impl TryInto<Box<s3::Bucket>> for S3Config {
+    type Error = anyhow::Error;
+
+    fn try_into(self) -> Result<Box<s3::Bucket>, Self::Error> {
+        let region = s3::Region::Custom {
+            region: self.region,
+            endpoint: self.endpoint,
+        };
+
+        let credentials = s3::creds::Credentials::new(
+            Some(&self.access_key_id),
+            Some(&self.secret_access_key),
+            None,
+            None,
+            None,
+        )?;
+
+        log::info!(
+            "Serving contents from bucket {} at {}",
+            &self.name,
+            region.endpoint()
+        );
+
+        let bucket = s3::Bucket::new(&self.name, region, credentials).map_err(|e| anyhow!(e));
+        if self.path_style {
+            bucket.map(|mut b| {
+                b.set_path_style();
+                b
+            })
+        } else {
+            bucket
+        }
+    }
+}

src/sizes.rs

@@ -0,0 +1,44 @@
+// SPDX-FileCopyrightText: © Matteo Settenvini <matteo.settenvini@montecristosoftware.eu>
+// SPDX-License-Identifier: EUPL-1.2
+
+pub fn bytes_to_human(bytes: u64) -> String {
+    use human_size::{Any, SpecificSize};
+
+    let size: f64 = bytes as f64;
+    let digits = size.log10().floor() as u32;
+    let mut order = digits / 3;
+    let unit = match order {
+        0 => Any::Byte,
+        1 => Any::Kilobyte,
+        2 => Any::Megabyte,
+        _ => {
+            order = 3; // Let's stop here.
+            Any::Gigabyte
+        }
+    };
+
+    format!(
+        "{:.3}",
+        SpecificSize::new(size / 10u64.pow(order * 3) as f64, unit)
+            .unwrap_or(SpecificSize::new(0., Any::Byte).unwrap())
+    )
+}
+
+// -------------------------------------------------------------
+
+#[cfg(test)]
+mod tests {
+    use rstest::rstest;
+
+    #[rstest]
+    #[case(1024, "1.024 kB")]
+    #[case(10240, "10.240 kB")]
+    #[case(1024*1024, "1.049 MB")]
+    #[case(1024*1024*1024, "1.074 GB")]
+    #[case(0, "0.000 B")]
+    #[case(u64::MAX, format!("{:.3} GB",u64::MAX as f64/(1_000_000_000.0)))]
+    #[case(u64::MIN, format!("{:.3} B",u64::MIN as f64))]
+    fn bytes_to_human(#[case] bytes: u64, #[case] expected: String) {
+        assert_eq!(super::bytes_to_human(bytes), expected);
+    }
+}

tests/common/minio.rs

@@ -0,0 +1,54 @@
+// SPDX-FileCopyrightText: © Matteo Settenvini <matteo.settenvini@montecristosoftware.eu>
+// SPDX-License-Identifier: EUPL-1.2
+
+use {
+    delegate::delegate,
+    std::borrow::Cow,
+    testcontainers::{
+        core::{ContainerPort, WaitFor},
+        Image,
+    },
+    testcontainers_modules::minio,
+};
+
+const MINIO_IMAGE_TAG: &'static str = "RELEASE.2024-09-22T00-33-43Z";
+
+pub struct MinIO {
+    inner: minio::MinIO,
+}
+
+impl Image for MinIO {
+    fn tag(&self) -> &str {
+        MINIO_IMAGE_TAG.into()
+    }
+
+    fn ready_conditions(&self) -> Vec<WaitFor> {
+        vec![WaitFor::message_on_stderr("API:")]
+    }
+
+    delegate! {
+        to self.inner {
+            fn name(&self) -> &str;
+            fn expose_ports(&self) -> &[ContainerPort];
+            fn env_vars(
+                &self,
+            ) -> impl IntoIterator<Item = (impl Into<Cow<'_, str>>, impl Into<Cow<'_, str>>)>;
+            fn mounts(&self) -> impl IntoIterator<Item = &testcontainers::core::Mount>;
+            fn copy_to_sources(&self) -> impl IntoIterator<Item = &testcontainers::CopyToContainer>;
+            fn entrypoint(&self) -> Option<&str>;
+            fn cmd(&self) -> impl IntoIterator<Item = impl Into<std::borrow::Cow<'_, str>>>;
+            fn exec_after_start(
+                &self,
+                cs: testcontainers::core::ContainerState,
+            ) -> Result<Vec<testcontainers::core::ExecCommand>, testcontainers::TestcontainersError>;
+        }
+    }
+}
+
+impl Default for MinIO {
+    fn default() -> Self {
+        Self {
+            inner: Default::default(),
+        }
+    }
+}

tests/common/mod.rs

@@ -0,0 +1,122 @@
+// SPDX-FileCopyrightText: © Matteo Settenvini <matteo.settenvini@montecristosoftware.eu>
+// SPDX-License-Identifier: EUPL-1.2
+
+mod minio;
+
+use {
+    anyhow::{anyhow, Result},
+    reqwest::Url,
+    std::{ptr::null_mut, str::FromStr},
+    testcontainers::{runners::AsyncRunner, ContainerAsync},
+    tokio::io::AsyncBufReadExt as _,
+};
+
+pub struct Test {
+    pub base_url: Url,
+    pub bucket: Box<s3::Bucket>,
+    pub serves3: tokio::process::Child,
+    pub _minio: ContainerAsync<minio::MinIO>,
+}
+
+const MAXIMUM_SERVES3_INIT_TIMEOUT: std::time::Duration = std::time::Duration::from_secs(5);
+
+const BUCKET_NAME: &'static str = "integration-test-bucket";
+const REGION: &'static str = "test-region";
+const ACCESS_KEY: &'static str = "minioadmin";
+const SECRET_KEY: &'static str = "minioadmin";
+
+impl Test {
+    pub async fn new() -> Result<Self> {
+        // NOTE: this testsuite was setup to work
+        // against a recent version of podman,
+        // which correctly distinguishes between
+        // stdout and stderr of the running container.
+
+        let image = minio::MinIO::default();
+        let container = image.start().await?;
+
+        let endpoint = format!(
+            "http://{host}:{port}",
+            host = container.get_host().await?,
+            port = container.get_host_port_ipv4(9000).await?
+        );
+
+        let credentials = s3::creds::Credentials::new(
+            Some(&ACCESS_KEY),
+            Some(&SECRET_KEY),
+            None,
+            None,
+            Some("test"),
+        )?;
+        let bucket = s3::Bucket::create_with_path_style(
+            &BUCKET_NAME,
+            s3::Region::Custom {
+                region: REGION.into(),
+                endpoint: endpoint.clone(),
+            },
+            credentials,
+            s3::BucketConfiguration::private(),
+        )
+        .await?
+        .bucket;
+
+        let bin = std::env!("CARGO_BIN_EXE_serves3");
+        let mut child = tokio::process::Command::new(bin)
+            .env("SERVES3_ADDRESS", "127.0.0.1")
+            .env("SERVES3_PORT", "0")
+            .env("SERVES3_LOG_LEVEL", "debug")
+            .env(
+                "SERVES3_S3_BUCKET",
+                format!(
+                    r#"{{
+                    name = "{name}",
+                    endpoint = "{endpoint}",
+                    region = "{region}",
+                    access_key_id = "{user}",
+                    secret_access_key = "{secret}",
+                    path_style = true
+                }}"#,
+                    name = BUCKET_NAME,
+                    endpoint = endpoint,
+                    region = &REGION,
+                    user = ACCESS_KEY,
+                    secret = SECRET_KEY
+                ),
+            )
+            .stdout(std::process::Stdio::piped())
+            .spawn()?;
+
+        let base_url = tokio::time::timeout(MAXIMUM_SERVES3_INIT_TIMEOUT, async {
+            let stdout = child.stdout.as_mut().unwrap();
+            let mut lines = tokio::io::BufReader::new(stdout).lines();
+            let re = regex::Regex::new("^Rocket has launched from (http://.+)$").unwrap();
+            while let Some(line) = lines.next_line().await? {
+                println!("{}", &line);
+                if let Some(captures) = re.captures(&line) {
+                    let url = captures.get(1).unwrap().as_str();
+                    return Ok(Url::from_str(url)?);
+                }
+            }
+
+            Err(anyhow!("Rocket did not print that it has started"))
+        })
+        .await??;
+
+        Ok(Self {
+            base_url,
+            bucket,
+            serves3: child,
+            _minio: container,
+        })
+    }
+}
+
+impl Drop for Test {
+    fn drop(&mut self) {
+        unsafe {
+            let pid = self.serves3.id().unwrap() as i32;
+            libc::kill(pid, libc::SIGTERM);
+            libc::waitpid(pid, null_mut(), 0);
+        }
+    }
+}

tests/integration.rs

@@ -0,0 +1,158 @@
+// SPDX-FileCopyrightText: © Matteo Settenvini <matteo.settenvini@montecristosoftware.eu>
+// SPDX-License-Identifier: EUPL-1.2
+
+mod common;
+
+use scraper::{Html, Selector};
+
+#[test_log::test(tokio::test)]
+async fn serves_files() -> anyhow::Result<()> {
+    let test = common::Test::new().await?;
+
+    test.bucket
+        .put_object("file.txt", "I am a file".as_bytes())
+        .await?;
+    test.bucket
+        .put_object("folder/file.txt", "I am a file in a folder".as_bytes())
+        .await?;
+
+    let resp = reqwest::get(test.base_url.join("file.txt")?).await?;
+    assert_eq!(resp.bytes().await?, "I am a file");
+
+    let resp = reqwest::get(test.base_url.join("folder/file.txt")?).await?;
+    assert_eq!(resp.bytes().await?, "I am a file in a folder");
+
+    Ok(())
+}
+
+#[test_log::test(tokio::test)]
+async fn serves_top_level_folder() -> anyhow::Result<()> {
+    let test = common::Test::new().await?;
+
+    test.bucket
+        .put_object("file.txt", "I am a file".as_bytes())
+        .await?;
+    test.bucket
+        .put_object("folder/file.txt", "I am a file in a folder".as_bytes())
+        .await?;
+
+    // Check that a file in the toplevel is listed:
+    let resp = reqwest::get(test.base_url.clone()).await?;
+    assert!(
+        resp.status().is_success(),
+        "Request failed with {}",
+        resp.status()
+    );
+    let text = resp.text().await?;
+    println!("{}", &text);
+    let document = Html::parse_document(&text);
+
+    let selector = Selector::parse(r#"h1"#).unwrap();
+    for title in document.select(&selector) {
+        assert_eq!(title.inner_html(), "/", "title doesn't match");
+    }
+
+    let selector =
+        Selector::parse(r#"table > tbody > tr:nth-child(1) > td:first-child > a"#).unwrap();
+    for item in document.select(&selector) {
+        assert_eq!(item.attr("href"), Some("folder/"));
+        assert_eq!(item.text().next(), Some("folder/"));
+    }
+
+    let selector =
+        Selector::parse(r#"table > tbody > tr:nth-child(2) > td:first-child > a"#).unwrap();
+    for item in document.select(&selector) {
+        assert_eq!(item.attr("href"), Some("file.txt"));
+        assert_eq!(item.text().next(), Some("file.txt"));
+    }
+
+    Ok(())
+}
+
+#[test_log::test(tokio::test)]
+async fn serves_second_level_folder() -> anyhow::Result<()> {
+    let test = common::Test::new().await?;
+
+    test.bucket
+        .put_object("file.txt", "I am a file".as_bytes())
+        .await?;
+    test.bucket
+        .put_object("folder/file.txt", "I am a file in a folder".as_bytes())
+        .await?;
+
+    // Check that a file in the second level is listed:
+    let resp = reqwest::get(test.base_url.join("folder/")?).await?;
+    assert!(
+        resp.status().is_success(),
+        "Request failed with {}",
+        resp.status()
+    );
+    let text = resp.text().await?;
+    println!("{}", &text);
+    let document = Html::parse_document(&text);
+
+    let selector = Selector::parse(r#"h1"#).unwrap();
+    for title in document.select(&selector) {
+        assert_eq!(title.inner_html(), "folder/", "title doesn't match");
+    }
+
+    let selector =
+        Selector::parse(r#"table > tbody > tr:nth-child(1) > td:first-child > a"#).unwrap();
+    for item in document.select(&selector) {
+        assert_eq!(item.attr("href"), Some("../"));
+        assert_eq!(item.inner_html(), "..");
+    }
+
+    let selector =
+        Selector::parse(r#"table > tbody > tr:nth-child(2) > td:first-child > a"#).unwrap();
+    for item in document.select(&selector) {
+        assert_eq!(item.attr("href"), Some("file.txt"));
+        assert_eq!(item.inner_html(), "file.txt");
+    }
+
+    Ok(())
+}
+
+#[test_log::test(tokio::test)]
+async fn serves_second_level_folder_without_ending_slash() -> anyhow::Result<()> {
+    let test = common::Test::new().await?;
+
+    test.bucket
+        .put_object("file.txt", "I am a file".as_bytes())
+        .await?;
+    test.bucket
+        .put_object("folder/file.txt", "I am a file in a folder".as_bytes())
+        .await?;
+
+    // Check that a file in the second level is listed even without an ending slash:
+    let resp = reqwest::get(test.base_url.join("folder")?).await?;
+    assert!(
+        resp.status().is_success(),
+        "Request failed with {}",
+        resp.status()
+    );
+    let text = resp.text().await?;
+    println!("{}", &text);
+    let document = Html::parse_document(&text);
+
+    let selector = Selector::parse(r#"h1"#).unwrap();
+    for title in document.select(&selector) {
+        assert_eq!(title.inner_html(), "folder/", "title doesn't match");
+    }
+
+    let selector =
+        Selector::parse(r#"table > tbody > tr:nth-child(1) > td:first-child > a"#).unwrap();
+    for item in document.select(&selector) {
+        assert_eq!(item.attr("href"), Some("../"));
+        assert_eq!(item.inner_html(), "..");
+    }
+
+    let selector =
+        Selector::parse(r#"table > tbody > tr:nth-child(2) > td:first-child > a"#).unwrap();
+    for item in document.select(&selector) {
+        assert_eq!(item.attr("href"), Some("file.txt"));
+        assert_eq!(item.inner_html(), "file.txt");
+    }
+
+    Ok(())
+}