feat(web/converse): Import repository

Imports the converse forum software I wrote a few years ago. I want to
clean this up a bit and try using Hotwire with it.

Note: The original repository was AGPL-3.0 licensed. I'm the copyright
holder and have relicensed it to GPL-3.0 in the commit that is being
merged.

Imported from: https://github.com/tazjin/converse

git-subtree-dir: web/converse
git-subtree-mainline: 386afdc794
git-subtree-split: 09168021e7
Change-Id: Ia8b587db5174ef5b3c52910d3d027199150c58e0

web/converse/src/main.rs

@@ -0,0 +1,223 @@
+// Copyright (C) 2018-2021 Vincent Ambo <tazjin@tvl.su>
+//
+// This file is part of Converse.
+//
+// This program is free software: you can redistribute it and/or
+// modify it under the terms of the GNU General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see
+// <https://www.gnu.org/licenses/>.
+
+#[macro_use]
+extern crate askama;
+
+#[macro_use]
+extern crate diesel;
+
+#[macro_use]
+extern crate failure;
+
+#[macro_use]
+extern crate log;
+
+#[macro_use]
+extern crate serde_derive;
+
+extern crate actix;
+extern crate actix_web;
+extern crate chrono;
+extern crate comrak;
+extern crate env_logger;
+extern crate futures;
+extern crate hyper;
+extern crate md5;
+extern crate mime_guess;
+extern crate r2d2;
+extern crate rand;
+extern crate reqwest;
+extern crate serde;
+extern crate serde_json;
+extern crate tokio;
+extern crate tokio_timer;
+extern crate url;
+extern crate url_serde;
+
+/// Simple macro used to reduce boilerplate when defining actor
+/// message types.
+macro_rules! message {
+    ( $t:ty, $r:ty ) => {
+        impl Message for $t {
+            type Result = $r;
+        }
+    }
+}
+
+pub mod db;
+pub mod errors;
+pub mod handlers;
+pub mod models;
+pub mod oidc;
+pub mod render;
+pub mod schema;
+
+use actix::prelude::*;
+use actix_web::*;
+use actix_web::http::Method;
+use actix_web::middleware::Logger;
+use actix_web::middleware::identity::{IdentityService, CookieIdentityPolicy};
+use db::*;
+use diesel::pg::PgConnection;
+use diesel::r2d2::{ConnectionManager, Pool};
+use handlers::*;
+use oidc::OidcExecutor;
+use rand::{OsRng, Rng};
+use render::Renderer;
+use std::env;
+
+fn config(name: &str) -> String {
+    env::var(name).expect(&format!("{} must be set", name))
+}
+
+fn config_default(name: &str, default: &str) -> String {
+    env::var(name).unwrap_or(default.into())
+}
+
+fn start_db_executor() -> Addr<Syn, DbExecutor> {
+    info!("Initialising database connection pool ...");
+    let db_url = config("DATABASE_URL");
+
+    let manager = ConnectionManager::<PgConnection>::new(db_url);
+    let pool = Pool::builder().build(manager).expect("Failed to initialise DB pool");
+
+    SyncArbiter::start(2, move || DbExecutor(pool.clone()))
+}
+
+fn schedule_search_refresh(db: Addr<Syn, DbExecutor>) {
+    use tokio::prelude::*;
+    use tokio::timer::Interval;
+    use std::time::{Duration, Instant};
+    use std::thread;
+
+    let task = Interval::new(Instant::now(), Duration::from_secs(60))
+        .from_err()
+        .for_each(move |_| db.send(db::RefreshSearchView).flatten())
+        .map_err(|err| error!("Error while updating search view: {}", err));
+
+    thread::spawn(|| tokio::run(task));
+}
+
+fn start_oidc_executor(base_url: &str) -> Addr<Syn, OidcExecutor> {
+    info!("Initialising OIDC integration ...");
+    let oidc_url = config("OIDC_DISCOVERY_URL");
+    let oidc_config = oidc::load_oidc(&oidc_url)
+        .expect("Failed to retrieve OIDC discovery document");
+
+    let oidc = oidc::OidcExecutor {
+        oidc_config,
+        client_id: config("OIDC_CLIENT_ID"),
+        client_secret: config("OIDC_CLIENT_SECRET"),
+        redirect_uri: format!("{}/oidc/callback", base_url),
+    };
+
+    oidc.start()
+}
+
+fn start_renderer() -> Addr<Syn, Renderer> {
+    let comrak = comrak::ComrakOptions{
+        github_pre_lang: true,
+        ext_strikethrough: true,
+        ext_table: true,
+        ext_autolink: true,
+        ext_tasklist: true,
+        ext_footnotes: true,
+        ext_tagfilter: true,
+        ..Default::default()
+    };
+
+    Renderer{ comrak }.start()
+}
+
+fn gen_session_key() -> [u8; 64] {
+    let mut key_bytes = [0; 64];
+    let mut rng = OsRng::new()
+        .expect("Failed to retrieve RNG for key generation");
+    rng.fill_bytes(&mut key_bytes);
+
+    key_bytes
+}
+
+fn start_http_server(base_url: String,
+                     db_addr: Addr<Syn, DbExecutor>,
+                     oidc_addr: Addr<Syn, OidcExecutor>,
+                     renderer_addr: Addr<Syn, Renderer>) {
+    info!("Initialising HTTP server ...");
+    let bind_host = config_default("CONVERSE_BIND_HOST", "127.0.0.1:4567");
+    let key = gen_session_key();
+    let require_login = config_default("REQUIRE_LOGIN", "true".into()) == "true";
+
+    server::new(move || {
+        let state = AppState {
+            db: db_addr.clone(),
+            oidc: oidc_addr.clone(),
+            renderer: renderer_addr.clone(),
+        };
+
+        let identity = IdentityService::new(
+            CookieIdentityPolicy::new(&key)
+                .name("converse_auth")
+                .path("/")
+                .secure(base_url.starts_with("https"))
+        );
+
+        let app = App::with_state(state)
+            .middleware(Logger::default())
+            .middleware(identity)
+            .resource("/", |r| r.method(Method::GET).with(forum_index))
+            .resource("/thread/new", |r| r.method(Method::GET).with(new_thread))
+            .resource("/thread/submit", |r| r.method(Method::POST).with3(submit_thread))
+            .resource("/thread/reply", |r| r.method(Method::POST).with3(reply_thread))
+            .resource("/thread/{id}", |r| r.method(Method::GET).with3(forum_thread))
+            .resource("/post/{id}/edit", |r| r.method(Method::GET).with3(edit_form))
+            .resource("/post/edit", |r| r.method(Method::POST).with3(edit_post))
+            .resource("/search", |r| r.method(Method::GET).with2(search_forum))
+            .resource("/oidc/login", |r| r.method(Method::GET).with(login))
+            .resource("/oidc/callback", |r| r.method(Method::POST).with3(callback))
+            .static_file("/static/highlight.css", include_bytes!("../static/highlight.css"))
+            .static_file("/static/highlight.js", include_bytes!("../static/highlight.js"))
+            .static_file("/static/styles.css", include_bytes!("../static/styles.css"));
+
+        if require_login {
+            app.middleware(RequireLogin)
+        } else {
+            app
+        }})
+        .bind(&bind_host).expect(&format!("Could not bind on '{}'", bind_host))
+        .start();
+}
+
+fn main() {
+    env_logger::init();
+
+    info!("Welcome to Converse! Hold on tight while we're getting ready.");
+    let sys = actix::System::new("converse");
+
+    let base_url = config("BASE_URL");
+
+    let db_addr = start_db_executor();
+    let oidc_addr = start_oidc_executor(&base_url);
+    let renderer_addr = start_renderer();
+
+    schedule_search_refresh(db_addr.clone());
+
+    start_http_server(base_url, db_addr, oidc_addr, renderer_addr);
+
+    sys.run();
+}