feat: read static files from the public folder

Cargo.toml

@@ -20,6 +20,8 @@ wasmtime-wasi = "2.0.2"
 anyhow = "1.0.66"
 wasi-common = "2.0.2"
 actix-web = "4"
+actix-files = "0.6.2"
+lazy_static = "1.4.0"
 env_logger = "0.9.0"
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0.85"

docs/docs/containers.md

@@ -22,5 +22,5 @@ docker run -v /path/to/handlers/on/host:/app -p 8080:8080 \
 
 ## Other usages
 
-Wasm Workers Server is stateless as far as the loaded handers are stateless (i.e. when they don't use the [Key / Value store](../features/key-value.md)). This makes the image very useful if you want to setup your own auto-scaling deployment.
+Wasm Workers Server is stateless as far as the loaded handers are stateless (i.e. when they don't use the [Key / Value store](./features/key-value.md)). This makes the image very useful if you want to setup your own auto-scaling deployment.
 

docs/docs/features/key-value.md

@@ -1,5 +1,5 @@
 ---
-sidebar_position: 2
+sidebar_position: 1
 ---
 
 # Key / Value Store

docs/docs/features/static-assets.md

@@ -0,0 +1,47 @@
+---
+sidebar_position: 2
+---
+
+# Static assets
+
+Wasm Workers Server allows you to serve any static asset required by your workers. For that, place any static asset in a `public` folder. It must be present in the root of the directory you're serving with `wws`.
+
+Note that all static assets are mounted on `/`, so `public` won't be present in their paths.
+
+For example, given the following folder structure:
+
+```bash
+.
+├── index.js
+└── public
+    └── images
+       └── intro.jpg
+    └── robots.txt
+```
+
+If you run `wws` in this folder, it will serve the following resources:
+
+* `/`: the response will be generated by the `index.js` worker
+* `/robots.txt`: the static `robots.txt` file
+* `/images/intro.jpg`: the static `intro.jpg` file
+
+## HTML files in public folder
+
+HTML files are supported inside the `public` folder. `wws` will serve those without requiring the `html` extension.
+
+For example, for the given folder structure:
+
+```bash
+.
+├── index.js
+└── public
+    └── images
+       └── intro.jpg
+    └── about.html
+```
+
+The `about.html` file will be served as `/about`.
+
+## Index file in public
+
+An `index.html` can be added to the `public` folder and it will be mounted in `/`. Note that workers have priority, so if there's an `/index.js` and `/public/index.html` files, the `/` route will be served by the former.

src/main.rs

@@ -1,11 +1,16 @@
 // Copyright 2022 VMware, Inc.
 // SPDX-License-Identifier: Apache-2.0
 
+#[macro_use]
+extern crate lazy_static;
+
 mod config;
 mod data;
 mod router;
 mod runner;
 
+use actix_files::{Files, NamedFile};
+use actix_web::dev::{fn_service, ServiceRequest, ServiceResponse};
 use actix_web::{
     http::StatusCode,
     middleware,
@@ -15,8 +20,18 @@ use actix_web::{
 use clap::Parser;
 use data::kv::KV;
 use runner::WasmOutput;
+use std::path::Path;
 use std::path::PathBuf;
-use std::{collections::HashMap, sync::RwLock};
+use std::{
+    collections::HashMap,
+    sync::{Arc, RwLock},
+};
+
+// Provide a static root_path so it can be used in the default_handler to manage
+// static assets.
+lazy_static! {
+    static ref ROOT_PATH: Arc<RwLock<PathBuf>> = Arc::new(RwLock::new(PathBuf::new()));
+}
 
 // Arguments
 #[derive(Parser, Debug)]
@@ -120,6 +135,14 @@ async fn debug(req: HttpRequest) -> impl Responder {
 async fn main() -> std::io::Result<()> {
     let args = Args::parse();
 
+    // Initialize root path so it can be used later in the default_handler
+    // for static assets. I have to do it in a clojure so the root_path
+    // reference is drop and the RwLock is released automatically.
+    {
+        let mut root_path = ROOT_PATH.write().unwrap();
+        *root_path = args.path.clone();
+    }
+
     std::env::set_var("RUST_LOG", "actix_web=info");
     env_logger::init();
 
@@ -169,6 +192,51 @@ async fn main() -> std::io::Result<()> {
             }
         }
 
+        // Serve static files from the static folder
+        app = app.service(
+            Files::new("/", &args.path.join("public"))
+                .index_file("index.html")
+                // This handler check if there's an HTML file in the public folder that
+                // can reply to the given request. For example, if someone request /about,
+                // this handler will look for a /public/about.html file.
+                .default_handler(fn_service(|req: ServiceRequest| async {
+                    let (req, _) = req.into_parts();
+                    // Avoid dots in the URI. If they are present, the extension
+                    // was passed so the file should be properly rendered.
+                    let uri_path = req.path().replace(".", "");
+                    let file;
+
+                    let rw_path = ROOT_PATH.read().unwrap();
+                    let base_path = rw_path.as_os_str();
+
+                    // Possible paths
+                    let index_folder_path =
+                        Path::new(base_path).join(format!("public{}/index.html", uri_path));
+                    let html_ext_path =
+                        Path::new(base_path).join(format!("public{}.html", uri_path));
+                    let public_404_path = Path::new(base_path).join("public").join("404.html");
+
+                    if uri_path.ends_with("/") && index_folder_path.exists() {
+                        file = NamedFile::open_async(index_folder_path).await;
+                    } else if !uri_path.ends_with("/") && html_ext_path.exists() {
+                        file = NamedFile::open_async(html_ext_path).await;
+                    } else {
+                        file = NamedFile::open_async(public_404_path).await;
+                    }
+
+                    match file {
+                        Ok(existing_file) => {
+                            let res = existing_file.into_response(&req);
+                            Ok(ServiceResponse::new(req, res))
+                        }
+                        Err(_) => {
+                            let mut res = HttpResponse::NotFound();
+                            Ok(ServiceResponse::new(req, res.body("")))
+                        }
+                    }
+                })),
+        );
+
         app
     })
     .bind(format!("{}:{}", args.hostname.as_str(), args.port))?;