Add maintenance subcommand

src/lib.rs

@@ -1,4 +1,5 @@
 mod static_handlers;
+mod maintenance;
 mod options;
 mod router;
 mod encryption;
@@ -19,8 +20,9 @@ mod ios;
 use actix_web::{rt, App, HttpServer, web, dev::Service};
 //use actix_cors::Cors;
 use std::time::Duration;
-pub use options::get_args;
+pub use options::{get_args, Commands};
 use runtime::get_data_path;
+pub use maintenance::run as run_maintenance;
 
 #[actix_web::main]
 pub async fn run_server(in_thread: bool) -> std::io::Result<()> {

src/main.rs

@@ -2,6 +2,9 @@
 #[cfg(not(feature = "library"))]
 fn main() -> std::io::Result<()> {
     let args = ew::get_args();
+    if let Some(ew::Commands::Maintenance { message }) = args.command {
+        return ew::run_maintenance(args.port, message);
+    }
     ew::runtime::update_data_path(&args.path);
     ew::runtime::update_masterdata_path(&args.masterdata);
     ew::run_server(false)

src/maintenance.rs

@@ -0,0 +1,121 @@
+use actix_web::{web, App, HttpRequest, HttpResponse, HttpServer};
+use jzon::object;
+
+#[actix_web::main]
+pub async fn run(port: u16, message: String) -> std::io::Result<()> {
+    let message = web::Data::new(message);
+    let server = HttpServer::new(move || {
+        App::new()
+            .app_data(message.clone())
+            .default_service(web::route().to(respond))
+    })
+    .bind(("0.0.0.0", port))?
+    .run();
+    println!("Maintenance server listening on http://0.0.0.0:{port}");
+    server.await
+}
+
+async fn respond(req: HttpRequest, message: web::Data<String>) -> HttpResponse {
+    let message = message.get_ref().as_str();
+    if req.path() == "/maintenance/maintenance.json" {
+        // The title screen requires HTTP 200, server=false, and an active UTC window.
+        return HttpResponse::Ok()
+            .insert_header(("Cache-Control", "no-store"))
+            .content_type("application/json")
+            .body(object! {
+                "opened_at": "1970-01-01 00:00:00",
+                "closed_at": "9999-01-01 00:00:00",
+                "message": message,
+                "server": false,
+                "gamelib": 0
+            }.dump());
+    }
+
+    let webui = req.path() == "/api/webui" || req.path().starts_with("/api/webui/");
+    let game_api = req.path() == "/api" || req.path().starts_with("/api/");
+    let browser = req.headers().get("Accept").and_then(|value| value.to_str().ok())
+        .is_some_and(|value| value.contains("text/html"));
+    if req.headers().contains_key("aoharu-asset-version") || (game_api && !webui && !browser) {
+        // Do not use global::send: its per-user clock can access the database.
+        let body = object! {
+            "code": 10,
+            "server_time": crate::router::global::timestamp(),
+            "message": message
+        }.dump();
+        return HttpResponse::Ok()
+            .insert_header(("Cache-Control", "no-store"))
+            .body(crate::encryption::encrypt_packet(&body).expect("packet encryption failed"));
+    }
+
+    let escaped = message.replace('&', "&amp;").replace('<', "&lt;").replace('>', "&gt;")
+        .replace('"', "&quot;").replace('\'', "&#39;");
+    HttpResponse::ServiceUnavailable()
+        .insert_header(("Cache-Control", "no-store"))
+        .content_type("text/html; charset=utf-8")
+        .body(include_str!("../web_assets/maintenance.html").replace("{{message}}", &escaped))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use actix_web::{http::{Method, StatusCode}, test};
+
+    const MESSAGE: &str = "Updating \"songs\" & <cards> — またね\nPlease wait.";
+
+    #[actix_web::test]
+    async fn title_check_is_active_and_preserves_message() {
+        let app = test::init_service(App::new().app_data(web::Data::new(MESSAGE.to_string()))
+            .default_service(web::route().to(respond))).await;
+        let req = test::TestRequest::get().uri("/maintenance/maintenance.json?cache=1").to_request();
+        let response = test::call_service(&app, req).await;
+        assert_eq!(response.status(), StatusCode::OK);
+        assert_eq!(response.headers().get("Cache-Control").unwrap(), "no-store");
+        let body = test::read_body(response).await;
+        let json = jzon::parse(std::str::from_utf8(&body).unwrap()).unwrap();
+        assert_eq!(json["message"].as_str(), Some(MESSAGE));
+        assert_eq!(json["server"].as_bool(), Some(false));
+        let now = crate::router::global::format_datetime(crate::router::global::timestamp());
+        assert!(json["opened_at"].as_str().unwrap() < now.as_str());
+        assert!(json["closed_at"].as_str().unwrap() > now.as_str());
+    }
+
+    #[actix_web::test]
+    async fn game_requests_get_encrypted_maintenance_without_reading_the_body() {
+        let app = test::init_service(App::new().app_data(web::Data::new(MESSAGE.to_string()))
+            .default_service(web::route().to(respond))).await;
+        for (path, header) in [("/api/start", false), ("/api/live/end", true),
+            ("/api/unknown", false), ("/v1.0/test", true), ("/anything", true)] {
+            let mut req = test::TestRequest::post().uri(path)
+                .insert_header(("aoharu-user-id", "12345")).set_payload("not an encrypted request");
+            if header { req = req.insert_header(("aoharu-asset-version", "old")); }
+            let response = test::call_service(&app, req.to_request()).await;
+            assert_eq!(response.status(), StatusCode::OK, "{path}");
+            let body = test::read_body(response).await;
+            let decoded = crate::encryption::decrypt_packet(std::str::from_utf8(&body).unwrap()).unwrap();
+            let json = jzon::parse(&decoded).unwrap();
+            assert_eq!(json["code"].as_i32(), Some(10));
+            assert_eq!(json["message"].as_str(), Some(MESSAGE));
+        }
+    }
+
+    #[actix_web::test]
+    async fn all_other_routes_and_methods_are_maintenance_only() {
+        let app = test::init_service(App::new().app_data(web::Data::new(MESSAGE.to_string()))
+            .default_service(web::route().to(respond))).await;
+        for path in ["/", "/maintenance.html", "/custom_song/upload", "/custom_card/delete",
+            "/custom_3dmv/upload", "/announcement/create", "/api/webui/login",
+            "/Android/hash/file", "/v1.0/test", "/api/user", "/unknown"] {
+            for method in [Method::GET, Method::POST, Method::PUT, Method::DELETE, Method::OPTIONS] {
+                let response = test::call_service(&app,
+                    test::TestRequest::default().method(method).uri(path)
+                        .insert_header(("Accept", "text/html")).to_request()).await;
+                assert_eq!(response.status(), StatusCode::SERVICE_UNAVAILABLE, "{path}");
+                let body = test::read_body(response).await;
+                let html = std::str::from_utf8(&body).unwrap();
+                assert!(html.contains("&lt;cards&gt;"));
+                assert!(html.contains("またね"));
+                assert!(!html.contains("<cards>"));
+            }
+        }
+    }
+}

src/options.rs

@@ -1,9 +1,12 @@
-use clap::Parser;
+use clap::{Parser, Subcommand};
 
 #[derive(Parser, Debug)]
 #[command(author, version, about, long_about = None)]
 pub struct Args {
-    #[arg(short, long, default_value_t = 8080, help = "Port to listen on")]
+    #[command(subcommand)]
+    pub command: Option<Commands>,
+
+    #[arg(short, long, global = true, default_value_t = 8080, help = "Port to listen on")]
     pub port: u16,
 
     #[arg(long, default_value = "./", help = "Path to store database files")]
@@ -102,8 +105,38 @@ pub struct Args {
     pub masterdata: String
 }
 
+#[derive(Subcommand, Debug)]
+pub enum Commands {
+    /// Start a maintenance-only server until stopped
+    Maintenance {
+        /// The message shown to the client
+        message: String,
+    },
+}
+
 pub fn get_args() -> Args {
     let mut args = Args::parse();
     crate::runtime::overlay_args(&mut args);
     args
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn maintenance_command_and_port() {
+        for argv in [
+            vec!["ew", "--port", "6017", "maintenance", "Updating songs"],
+            vec!["ew", "maintenance", "Updating songs", "--port", "6017"],
+        ] {
+            let args = Args::try_parse_from(argv).unwrap();
+            assert_eq!(args.port, 6017);
+            assert!(matches!(args.command, Some(Commands::Maintenance { message }) if message == "Updating songs"));
+        }
+        assert!(Args::try_parse_from(["ew", "maintenance"]).is_err());
+        let normal = Args::try_parse_from(["ew"]).unwrap();
+        assert!(normal.command.is_none());
+        assert_eq!(normal.port, 8080);
+    }
+}

web_assets/maintenance.html

@@ -0,0 +1,21 @@
+<!doctype html>
+<html lang="en">
+<head>
+    <meta charset="utf-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <title>Maintenance</title>
+    <style>
+        body { margin: 0; min-height: 100vh; display: grid; place-items: center;
+            background: #0b0e1a; color: #e8ebf5; font-family: system-ui, sans-serif; }
+        main { max-width: 32rem; padding: 2rem; text-align: center; }
+        h1 { font-size: 1.6rem; }
+        p { color: #c3c9dd; line-height: 1.6; white-space: pre-wrap; overflow-wrap: anywhere; }
+    </style>
+</head>
+<body>
+    <main>
+        <h1>The server is down for maintenance</h1>
+        <p>{{message}}</p>
+    </main>
+</body>
+</html>