finish minimum version

.gitignore

@@ -1 +1,2 @@
 /target
+.env

Cargo.toml

@@ -7,7 +7,7 @@ edition = "2018"
 
 [dependencies]
 actix-web = { version = "4.0.0-beta.4", features = [ "rustls" ] }
-awc = "3.0.0-beta.3"
+reqwest = { version = "0.11", features = ["json"] }
 parking_lot = "0.11"
 base64 = "0.13"
 sodiumoxide = "0.2"
@@ -23,3 +23,7 @@ simple_logger = "1"
 lru = "0.6"
 futures = "0.3"
 bytes = "1"
+cacache = "8"
+ssri = "5"
+bincode = "1"
+ctrlc = "3"

src/cache.rs

@@ -0,0 +1,202 @@
+use std::{fmt::Display, path::PathBuf};
+
+use futures::future::join_all;
+use log::warn;
+use lru::LruCache;
+use serde::{Deserialize, Serialize};
+use ssri::Integrity;
+
+#[derive(PartialEq, Eq, Hash, Clone)]
+pub struct CacheKey(pub String, pub String, pub bool);
+
+impl Display for CacheKey {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        if self.2 {
+            write!(f, "saver/{}/{}", self.0, self.1)
+        } else {
+            write!(f, "data/{}/{}", self.0, self.1)
+        }
+    }
+}
+
+#[derive(Serialize, Deserialize)]
+pub struct CachedImage {
+    pub data: Vec<u8>,
+    pub content_type: Option<Vec<u8>>,
+    pub content_length: Option<Vec<u8>>,
+    pub last_modified: Option<Vec<u8>>,
+}
+
+impl CachedImage {
+    fn len(&self) -> usize {
+        self.data.capacity()
+            + self
+                .content_type
+                .as_ref()
+                .map(Vec::capacity)
+                .unwrap_or_default()
+            + self
+                .content_length
+                .as_ref()
+                .map(Vec::capacity)
+                .unwrap_or_default()
+            + self
+                .last_modified
+                .as_ref()
+                .map(Vec::capacity)
+                .unwrap_or_default()
+    }
+
+    fn shrink_to_fit(&mut self) {
+        self.data.shrink_to_fit();
+        self.content_length.as_mut().map(Vec::shrink_to_fit);
+        self.last_modified.as_mut().map(Vec::shrink_to_fit);
+    }
+}
+
+pub struct Cache {
+    in_memory: LruCache<CacheKey, CachedImage>,
+    memory_max_size: usize,
+    memory_cur_size: usize,
+
+    on_disk: LruCache<CacheKey, Integrity>,
+    disk_path: PathBuf,
+    disk_max_size: usize,
+    disk_cur_size: usize,
+}
+
+impl Cache {
+    pub fn new(memory_max_size: usize, disk_max_size: usize, disk_path: PathBuf) -> Self {
+        Self {
+            in_memory: LruCache::unbounded(),
+            memory_max_size,
+            memory_cur_size: 0,
+            on_disk: LruCache::unbounded(),
+            disk_path,
+            disk_max_size,
+            disk_cur_size: 0,
+        }
+    }
+
+    pub async fn get(&mut self, key: &CacheKey) -> Option<&CachedImage> {
+        if self.in_memory.contains(key) {
+            return self.in_memory.get(key);
+        }
+
+        if let Some(disk_key) = self.on_disk.pop(key) {
+            // extract from disk, if it exists
+            let bytes = cacache::read_hash(&self.disk_path, &disk_key).await.ok()?;
+            // We don't particularly care if we fail to delete from disk since
+            // if it's an error it means it's already been dropped.
+            cacache::remove_hash(&self.disk_path, &disk_key).await.ok();
+            self.disk_cur_size -= bytes.len();
+            let cached_image: CachedImage = match bincode::deserialize(&bytes) {
+                Ok(image) => image,
+                Err(e) => {
+                    warn!("Failed to serialize on-disk data?! {}", e);
+                    return None;
+                }
+            };
+
+            // put into in-memory
+            self.memory_cur_size += cached_image.len();
+            self.put(key.clone(), cached_image).await;
+        }
+
+        None
+    }
+
+    pub async fn put(&mut self, key: CacheKey, mut image: CachedImage) {
+        image.shrink_to_fit();
+        let mut hot_evicted = vec![];
+        let new_img_size = image.len();
+
+        if self.memory_max_size >= new_img_size {
+            // Evict oldest entires to make space for new image.
+            while new_img_size + self.memory_cur_size > self.memory_max_size {
+                match self.in_memory.pop_lru() {
+                    Some((key, evicted_image)) => {
+                        self.memory_cur_size -= evicted_image.len();
+                        hot_evicted.push((key, evicted_image));
+                    }
+                    None => unreachable!(concat!(
+                        "Invariant violated. Cache is empty but we already ",
+                        "guaranteed we can remove items from cache to make space."
+                    )),
+                }
+            }
+
+            self.in_memory.put(key, image);
+            self.memory_cur_size += new_img_size;
+        } else {
+            // Image was larger than memory capacity, push directly into cold
+            // storage.
+            self.push_into_cold(key, image).await;
+        }
+
+        // Push evicted hot entires into cold storage.
+        for (key, image) in hot_evicted {
+            self.push_into_cold(key, image).await;
+        }
+    }
+
+    async fn push_into_cold(&mut self, key: CacheKey, image: CachedImage) {
+        let image = bincode::serialize(&image).unwrap(); // This should never fail.
+        let new_img_size = image.len();
+        let mut to_drop = vec![];
+
+        if self.disk_max_size >= new_img_size {
+            // Add images to drop from cold cache into a queue
+            while new_img_size + self.disk_cur_size > self.disk_max_size {
+                match self.on_disk.pop_lru() {
+                    Some((key, disk_key)) => {
+                        // Basically, the assumption here is that if the meta
+                        // data was deleted, we can't assume that deleting the
+                        // value will yield any free space back, so we assume a
+                        // size of zero while this is the case. This also means
+                        // that we automatically drop broken links as well.
+                        let on_disk_size = cacache::metadata(&self.disk_path, key.to_string())
+                            .await
+                            .unwrap_or_default()
+                            .map(|metadata| metadata.size)
+                            .unwrap_or_default();
+                        self.disk_cur_size -= on_disk_size;
+
+                        to_drop.push(disk_key);
+                    }
+                    None => unreachable!(concat!(
+                        "Invariant violated. Cache is empty but we already ",
+                        "guaranteed we can remove items from cache to make space."
+                    )),
+                }
+            }
+        } else {
+            warn!(
+                "Got request to push file larger than maximum disk cache. Refusing to insert on disk! {}",
+                key
+            );
+            return;
+        }
+
+        let mut futs = vec![];
+        for key in &to_drop {
+            futs.push(cacache::remove_hash(&self.disk_path, key));
+        }
+        // Run all cold caching in parallel, we don't care if the removal fails
+        // because it just means it's already been removed.
+        join_all(futs).await;
+
+        let new_disk_key = match cacache::write(&self.disk_path, key.to_string(), image).await {
+            Ok(key) => key,
+            Err(e) => {
+                warn!(
+                    "failed to write to disk cache, dropping value instead: {}",
+                    e
+                );
+                return;
+            }
+        };
+        self.on_disk.put(key.clone(), new_disk_key);
+        self.disk_cur_size += new_img_size;
+    }
+}

src/main.rs

@@ -2,135 +2,36 @@
 #![allow(clippy::future_not_send)] // We're end users, so this is ok
 
 use std::env::{self, VarError};
+use std::path::PathBuf;
+use std::sync::atomic::AtomicBool;
+use std::sync::Arc;
 use std::time::Duration;
-use std::{num::ParseIntError, sync::Arc};
+use std::{num::ParseIntError, sync::atomic::Ordering};
 
-use crate::ping::Tls;
+use actix_web::rt::{spawn, time, System};
-use actix_web::rt::{spawn, time};
+use actix_web::web;
 use actix_web::web::Data;
 use actix_web::{App, HttpServer};
-use awc::{error::SendRequestError, Client};
+use log::{error, warn, LevelFilter};
-use log::{debug, error, info, warn};
-use lru::LruCache;
 use parking_lot::RwLock;
-use ping::{Request, Response};
+use rustls::{NoClientAuth, ServerConfig};
-use rustls::sign::{CertifiedKey, RSASigningKey};
-use rustls::PrivateKey;
-use rustls::{Certificate, NoClientAuth, ResolvesServerCert, ServerConfig};
 use simple_logger::SimpleLogger;
-use sodiumoxide::crypto::box_::PrecomputedKey;
+use state::{RwLockServerState, ServerState};
+use stop::send_stop;
 use thiserror::Error;
-use url::Url;
 
+mod cache;
 mod ping;
 mod routes;
+mod state;
 mod stop;
 
-const CONTROL_CENTER_PING_URL: &str = "https://api.mangadex.network/ping";
-
 #[macro_export]
 macro_rules! client_api_version {
     () => {
         "30"
     };
 }
-
-struct ServerState {
-    precomputed_key: PrecomputedKey,
-    image_server: Url,
-    tls_config: Tls,
-    disabled_tokens: bool,
-    url: String,
-    cache: LruCache<(String, String, bool), CachedImage>,
-}
-
-struct CachedImage {
-    data: Vec<u8>,
-    content_type: Option<Vec<u8>>,
-    content_length: Option<Vec<u8>>,
-    last_modified: Option<Vec<u8>>,
-}
-
-impl ServerState {
-    async fn init(config: &Config) -> Result<Self, ()> {
-        let resp = Client::new()
-            .post(CONTROL_CENTER_PING_URL)
-            .send_json(&Request::from(config))
-            .await;
-
-        match resp {
-            Ok(mut resp) => match resp.json::<Response>().await {
-                Ok(resp) => {
-                    let key = resp
-                        .token_key
-                        .and_then(|key| {
-                            if let Some(key) = PrecomputedKey::from_slice(key.as_bytes()) {
-                                Some(key)
-                            } else {
-                                error!("Failed to parse token key: got {}", key);
-                                None
-                            }
-                        })
-                        .unwrap();
-
-                    if resp.compromised {
-                        warn!("Got compromised response from control center!");
-                    }
-
-                    if resp.paused {
-                        debug!("Got paused response from control center.");
-                    }
-
-                    info!("This client's URL has been set to {}", resp.url);
-
-                    if resp.disabled_tokens {
-                        info!("This client will not validated tokens");
-                    }
-
-                    Ok(Self {
-                        precomputed_key: key,
-                        image_server: resp.image_server,
-                        tls_config: resp.tls.unwrap(),
-                        disabled_tokens: resp.disabled_tokens,
-                        url: resp.url,
-                        cache: LruCache::new(1000),
-                    })
-                }
-                Err(e) => {
-                    warn!("Got malformed response: {}", e);
-                    Err(())
-                }
-            },
-            Err(e) => match e {
-                SendRequestError::Timeout => {
-                    error!("Response timed out to control server. Is MangaDex down?");
-                    Err(())
-                }
-                e => {
-                    warn!("Failed to send request: {}", e);
-                    Err(())
-                }
-            },
-        }
-    }
-}
-
-pub struct RwLockServerState(RwLock<ServerState>);
-
-impl ResolvesServerCert for RwLockServerState {
-    fn resolve(&self, _: rustls::ClientHello) -> Option<CertifiedKey> {
-        let read_guard = self.0.read();
-        Some(CertifiedKey {
-            cert: vec![Certificate(read_guard.tls_config.certificate.clone())],
-            key: Arc::new(Box::new(
-                RSASigningKey::new(&PrivateKey(read_guard.tls_config.private_key.clone())).unwrap(),
-            )),
-            ocsp: None,
-            sct_list: None,
-        })
-    }
-}
-
 #[derive(Error, Debug)]
 enum ServerError {
     #[error("There was a failure parsing config")]
@@ -141,13 +42,29 @@ enum ServerError {
 
 #[actix_web::main]
 async fn main() -> Result<(), std::io::Error> {
+    // It's ok to fail early here, it would imply we have a invalid config.
     dotenv::dotenv().ok();
-    SimpleLogger::new().init().unwrap();
+    SimpleLogger::new()
-
+        .with_level(LevelFilter::Info)
+        .init()
+        .unwrap();
     let config = Config::new().unwrap();
     let port = config.port;
-
     let server = ServerState::init(&config).await.unwrap();
+
+    // Set ctrl+c to send a stop message
+    let running = Arc::new(AtomicBool::new(true));
+    let r = running.clone();
+    let client_secret = config.secret.clone();
+    ctrlc::set_handler(move || {
+        let client_secret = client_secret.clone();
+        System::new().block_on(async move {
+            send_stop(&client_secret).await;
+        });
+        r.store(false, Ordering::SeqCst);
+    })
+    .expect("Error setting Ctrl-C handler");
+
     let data_0 = Arc::new(RwLockServerState(RwLock::new(server)));
     let data_1 = Arc::clone(&data_0);
     let data_2 = Arc::clone(&data_0);
@@ -167,32 +84,52 @@ async fn main() -> Result<(), std::io::Error> {
     HttpServer::new(move || {
         App::new()
             .service(routes::token_data)
+            .service(routes::no_token_data)
+            .service(routes::token_data_saver)
+            .service(routes::no_token_data_saver)
+            .route("{tail:.*}", web::get().to(routes::default))
             .app_data(Data::from(Arc::clone(&data_1)))
     })
     .shutdown_timeout(60)
     .bind_rustls(format!("0.0.0.0:{}", port), tls_config)?
     .run()
-    .await
+    .await?;
+
+    // Waiting for us to finish sending stop message
+    while running.load(Ordering::SeqCst) {
+        std::thread::sleep(Duration::from_millis(250));
+    }
+
+    Ok(())
 }
 
 pub struct Config {
     secret: String,
     port: u16,
+    memory_quota: usize,
     disk_quota: usize,
+    disk_path: PathBuf,
     network_speed: usize,
 }
 
 impl Config {
     fn new() -> Result<Self, ServerError> {
         let secret = env::var("CLIENT_SECRET")?;
-        let port = env::var("PORT")?.parse::<u16>()?;
+        let port = env::var("PORT")?.parse()?;
-        let disk_quota = env::var("MAX_STORAGE_BYTES")?.parse::<usize>()?;
+        let disk_quota = env::var("DISK_CACHE_QUOTA_BYTES")?.parse()?;
-        let network_speed = env::var("MAX_NETWORK_SPEED")?.parse::<usize>()?;
+        let memory_quota = env::var("MEM_CACHE_QUOTA_BYTES")?.parse()?;
+        let network_speed = env::var("MAX_NETWORK_SPEED")?.parse()?;
+        let disk_path = env::var("DISK_CACHE_PATH")
+            .unwrap_or("./cache".to_string())
+            .parse()
+            .unwrap();
 
         Ok(Self {
             secret,
             port,
             disk_quota,
+            memory_quota,
+            disk_path,
             network_speed,
         })
     }

src/ping.rs

@@ -1,14 +1,16 @@
 use std::sync::Arc;
 
-use awc::{error::SendRequestError, Client};
 use log::{debug, error, info, warn};
 use serde::{Deserialize, Serialize};
 use sodiumoxide::crypto::box_::PrecomputedKey;
 use url::Url;
 
-use crate::{client_api_version, Config, RwLockServerState, CONTROL_CENTER_PING_URL};
+use crate::state::RwLockServerState;
+use crate::{client_api_version, Config};
 
-#[derive(Serialize)]
+pub const CONTROL_CENTER_PING_URL: &str = "https://api.mangadex.network/ping";
+
+#[derive(Serialize, Debug)]
 pub struct Request<'a> {
     secret: &'a str,
     port: u16,
@@ -44,7 +46,7 @@ impl<'a> From<&'a Config> for Request<'a> {
     }
 }
 
-#[derive(Deserialize)]
+#[derive(Deserialize, Debug)]
 pub struct Response {
     pub image_server: Url,
     pub latest_build: usize,
@@ -52,38 +54,40 @@ pub struct Response {
     pub token_key: Option<String>,
     pub compromised: bool,
     pub paused: bool,
-    pub disabled_tokens: bool,
+    pub force_tokens: bool,
     pub tls: Option<Tls>,
 }
 
-#[derive(Deserialize)]
+#[derive(Deserialize, Debug)]
 pub struct Tls {
     pub created_at: String,
-    pub private_key: Vec<u8>,
+    pub private_key: String,
-    pub certificate: Vec<u8>,
+    pub certificate: String,
 }
 
 pub async fn update_server_state(req: &Config, data: &mut Arc<RwLockServerState>) {
     let req = Request::from_config_and_state(req, data);
-    let resp = Client::new()
+    let client = reqwest::Client::new();
-        .post(CONTROL_CENTER_PING_URL)
+    let resp = client.post(CONTROL_CENTER_PING_URL).json(&req).send().await;
-        .send_json(&req)
-        .await;
     match resp {
-        Ok(mut resp) => match resp.json::<Response>().await {
+        Ok(resp) => match resp.json::<Response>().await {
             Ok(resp) => {
                 let mut write_guard = data.0.write();
 
                 write_guard.image_server = resp.image_server;
 
                 if let Some(key) = resp.token_key {
-                    match PrecomputedKey::from_slice(key.as_bytes()) {
+                    if let Some(key) = base64::decode(&key)
-                        Some(key) => write_guard.precomputed_key = key,
+                        .ok()
-                        None => error!("Failed to parse token key: got {}", key),
+                        .and_then(|k| PrecomputedKey::from_slice(&k))
+                    {
+                        write_guard.precomputed_key = key;
+                    } else {
+                        error!("Failed to parse token key: got {}", key);
                     }
                 }
 
-                write_guard.disabled_tokens = resp.disabled_tokens;
+                write_guard.force_tokens = resp.force_tokens;
 
                 if let Some(tls) = resp.tls {
                     write_guard.tls_config = tls;
@@ -104,7 +108,7 @@ pub async fn update_server_state(req: &Config, data: &mut Arc<RwLockServerState>
             Err(e) => warn!("Got malformed response: {}", e),
         },
         Err(e) => match e {
-            SendRequestError::Timeout => {
+            e if e.is_timeout() => {
                 error!("Response timed out to control server. Is MangaDex down?")
             }
             e => warn!("Failed to send request: {}", e),

src/routes.rs

@@ -7,19 +7,20 @@ use actix_web::http::header::{
 };
 use actix_web::web::Path;
 use actix_web::{get, web::Data, HttpRequest, HttpResponse, Responder};
-use awc::Client;
 use base64::DecodeError;
 use bytes::Bytes;
 use chrono::{DateTime, Utc};
 use futures::stream;
-use log::{error, warn};
+use log::{error, info, warn};
 use serde::Deserialize;
 use sodiumoxide::crypto::box_::{open_precomputed, Nonce, PrecomputedKey, NONCEBYTES};
 use thiserror::Error;
 
-use crate::{client_api_version, CachedImage, RwLockServerState};
+use crate::cache::{CacheKey, CachedImage};
+use crate::client_api_version;
+use crate::state::RwLockServerState;
 
-const BASE64_CONFIG: base64::Config = base64::Config::new(base64::CharacterSet::UrlSafe, false);
+pub const BASE64_CONFIG: base64::Config = base64::Config::new(base64::CharacterSet::UrlSafe, false);
 
 const SERVER_ID_STRING: &str = concat!(
     env!("CARGO_CRATE_NAME"),
@@ -50,7 +51,7 @@ async fn token_data(
     path: Path<(String, String, String)>,
 ) -> impl Responder {
     let (token, chapter_hash, file_name) = path.into_inner();
-    if !state.0.read().disabled_tokens {
+    if state.0.read().force_tokens {
         if let Err(e) = validate_token(&state.0.read().precomputed_key, token, &chapter_hash) {
             return ServerResponse::TokenValidationError(e);
         }
@@ -65,7 +66,7 @@ async fn token_data_saver(
     path: Path<(String, String, String)>,
 ) -> impl Responder {
     let (token, chapter_hash, file_name) = path.into_inner();
-    if !state.0.read().disabled_tokens {
+    if state.0.read().force_tokens {
         if let Err(e) = validate_token(&state.0.read().precomputed_key, token, &chapter_hash) {
             return ServerResponse::TokenValidationError(e);
         }
@@ -91,6 +92,24 @@ async fn no_token_data_saver(
     fetch_image(state, chapter_hash, file_name, true).await
 }
 
+pub async fn default(state: Data<RwLockServerState>, req: HttpRequest) -> impl Responder {
+    let path = &format!(
+        "{}{}",
+        state.0.read().image_server,
+        req.path().chars().skip(1).collect::<String>()
+    );
+    info!("Got unknown path, just proxying: {}", path);
+    let resp = reqwest::get(path).await.unwrap();
+    let content_type = resp.headers().get(CONTENT_TYPE);
+    let mut resp_builder = HttpResponseBuilder::new(resp.status());
+    if let Some(content_type) = content_type {
+        resp_builder.insert_header((CONTENT_TYPE, content_type));
+    }
+    push_headers(&mut resp_builder);
+
+    ServerResponse::HttpResponse(resp_builder.body(resp.bytes().await.unwrap_or_default()))
+}
+
 #[derive(Error, Debug)]
 enum TokenValidationError {
     #[error("Failed to decode base64 token.")]
@@ -165,26 +184,46 @@ async fn fetch_image(
     file_name: String,
     is_data_saver: bool,
 ) -> ServerResponse {
-    let key = (chapter_hash, file_name, is_data_saver);
+    let key = CacheKey(chapter_hash, file_name, is_data_saver);
 
-    if let Some(cached) = state.0.write().cache.get(&key) {
+    if let Some(cached) = state.0.write().cache.get(&key).await {
         return construct_response(cached);
     }
 
     let mut state = state.0.write();
     let resp = if is_data_saver {
-        Client::new().get(format!(
+        reqwest::get(format!(
             "{}/data-saver/{}/{}",
             state.image_server, &key.1, &key.2
         ))
     } else {
-        Client::new().get(format!("{}/data/{}/{}", state.image_server, &key.1, &key.2))
+        reqwest::get(format!("{}/data/{}/{}", state.image_server, &key.1, &key.2))
     }
-    .send()
     .await;
 
     match resp {
-        Ok(mut resp) => {
+        Ok(resp) => {
+            let content_type = resp.headers().get(CONTENT_TYPE);
+
+            let is_image = content_type
+                .map(|v| String::from_utf8_lossy(v.as_ref()).contains("image/"))
+                .unwrap_or_default();
+            if resp.status() != 200 || !is_image {
+                warn!(
+                    "Got non-OK or non-image response code from upstream, proxying and not caching result.",
+                );
+
+                let mut resp_builder = HttpResponseBuilder::new(resp.status());
+                if let Some(content_type) = content_type {
+                    resp_builder.insert_header((CONTENT_TYPE, content_type));
+                }
+                push_headers(&mut resp_builder);
+
+                return ServerResponse::HttpResponse(
+                    resp_builder.body(resp.bytes().await.unwrap_or_default()),
+                );
+            }
+
             let headers = resp.headers();
             let content_type = headers.get(CONTENT_TYPE).map(AsRef::as_ref).map(Vec::from);
             let content_length = headers
@@ -192,7 +231,7 @@ async fn fetch_image(
                 .map(AsRef::as_ref)
                 .map(Vec::from);
             let last_modified = headers.get(LAST_MODIFIED).map(AsRef::as_ref).map(Vec::from);
-            let body = resp.body().await;
+            let body = resp.bytes().await;
             match body {
                 Ok(bytes) => {
                     let cached = CachedImage {
@@ -202,7 +241,7 @@ async fn fetch_image(
                         last_modified,
                     };
                     let resp = construct_response(&cached);
-                    state.cache.put(key, cached);
+                    state.cache.put(key, cached).await;
                     return resp;
                 }
                 Err(e) => {

src/state.rs

@@ -0,0 +1,119 @@
+use std::{io::BufReader, sync::Arc};
+
+use crate::cache::Cache;
+use crate::ping::{Request, Response, Tls, CONTROL_CENTER_PING_URL};
+use crate::Config;
+use log::{debug, error, info, warn};
+use parking_lot::RwLock;
+use rustls::internal::pemfile::{certs, rsa_private_keys};
+use rustls::sign::{CertifiedKey, RSASigningKey};
+use rustls::ResolvesServerCert;
+use sodiumoxide::crypto::box_::PrecomputedKey;
+use url::Url;
+
+pub struct ServerState {
+    pub precomputed_key: PrecomputedKey,
+    pub image_server: Url,
+    pub tls_config: Tls,
+    pub force_tokens: bool,
+    pub url: String,
+    pub cache: Cache,
+}
+
+impl ServerState {
+    pub async fn init(config: &Config) -> Result<Self, ()> {
+        let resp = reqwest::Client::new()
+            .post(CONTROL_CENTER_PING_URL)
+            .json(&Request::from(config))
+            .send()
+            .await;
+
+        match resp {
+            Ok(resp) => match resp.json::<Response>().await {
+                Ok(resp) => {
+                    let key = resp
+                        .token_key
+                        .and_then(|key| {
+                            if let Some(key) = base64::decode(&key)
+                                .ok()
+                                .and_then(|k| PrecomputedKey::from_slice(&k))
+                            {
+                                Some(key)
+                            } else {
+                                error!("Failed to parse token key: got {}", key);
+                                None
+                            }
+                        })
+                        .unwrap();
+
+                    if resp.compromised {
+                        warn!("Got compromised response from control center!");
+                    }
+
+                    if resp.paused {
+                        debug!("Got paused response from control center.");
+                    }
+
+                    info!("This client's URL has been set to {}", resp.url);
+
+                    if resp.force_tokens {
+                        info!("This client will validate tokens");
+                    }
+
+                    Ok(Self {
+                        precomputed_key: key,
+                        image_server: resp.image_server,
+                        tls_config: resp.tls.unwrap(),
+                        force_tokens: resp.force_tokens,
+                        url: resp.url,
+                        cache: Cache::new(
+                            config.memory_quota,
+                            config.disk_quota,
+                            config.disk_path.clone(),
+                        ),
+                    })
+                }
+                Err(e) => {
+                    warn!("Got malformed response: {}", e);
+                    Err(())
+                }
+            },
+            Err(e) => match e {
+                e if e.is_timeout() => {
+                    error!("Response timed out to control server. Is MangaDex down?");
+                    Err(())
+                }
+                e => {
+                    warn!("Failed to send request: {}", e);
+                    Err(())
+                }
+            },
+        }
+    }
+}
+
+pub struct RwLockServerState(pub RwLock<ServerState>);
+
+impl ResolvesServerCert for RwLockServerState {
+    fn resolve(&self, _: rustls::ClientHello) -> Option<CertifiedKey> {
+        let read_guard = self.0.read();
+        let priv_key = rsa_private_keys(&mut BufReader::new(
+            read_guard.tls_config.private_key.as_bytes(),
+        ))
+        .ok()?
+        .pop()
+        .unwrap();
+
+        let certs = certs(&mut BufReader::new(
+            read_guard.tls_config.certificate.as_bytes(),
+        ))
+        .ok()?;
+
+        Some(CertifiedKey {
+            cert: certs,
+            key: Arc::new(Box::new(RSASigningKey::new(&priv_key).unwrap())),
+            ocsp: None,
+            sct_list: None,
+        })
+    }
+}

src/stop.rs

@@ -1,3 +1,29 @@
-struct StopRequest {
+use log::{info, warn};
-    secret: String,
+use serde::Serialize;
+
+const CONTROL_CENTER_STOP_URL: &str = "https://api.mangadex.network/ping";
+
+#[derive(Serialize)]
+struct StopRequest<'a> {
+    secret: &'a str,
+}
+
+pub async fn send_stop(secret: &str) {
+    let request = StopRequest { secret };
+    let client = reqwest::Client::new();
+    match client
+        .post(CONTROL_CENTER_STOP_URL)
+        .json(&request)
+        .send()
+        .await
+    {
+        Ok(resp) => {
+            if resp.status() == 200 {
+                info!("Successfully sent stop message.");
+            } else {
+                warn!("Got weird response from server: {:?}", resp.headers());
+            }
+        }
+        Err(e) => warn!("Got error while sending stop message: {}", e),
+    }
 }