debug streaming

.gitignore

@@ -1,2 +1,3 @@
 /target
 .env
+cache

Cargo.lock

@@ -1000,6 +1000,7 @@ dependencies = [
  "ssri",
  "thiserror",
  "tokio",
+ "tokio-util",
  "url",
 ]
 

Cargo.toml

@@ -33,6 +33,7 @@ sodiumoxide = "0.2"
 ssri = "5"
 thiserror = "1"
 tokio = { version = "1", features = [ "full", "parking_lot" ] }
+tokio-util = { version = "0.6", features = [ "codec" ] }
 url = { version = "2", features = [ "serde" ] }
 
 [profile.release]

src/cache/fs.rs

@@ -1,20 +1,22 @@
 use actix_web::error::PayloadError;
-use bytes::BytesMut;
-use futures::{Future, Stream, StreamExt};
+use futures::{Stream, StreamExt};
+use log::debug;
 use once_cell::sync::Lazy;
+use std::collections::HashMap;
+use std::fmt::Display;
 use std::path::{Path, PathBuf};
 use std::pin::Pin;
 use std::sync::atomic::{AtomicU8, Ordering};
 use std::sync::Arc;
 use std::task::{Context, Poll};
 use std::time::Duration;
-use std::{collections::HashMap, fmt::Display};
-use tokio::fs::{remove_file, File};
+use tokio::fs::{create_dir_all, remove_file, File};
 use tokio::io::{AsyncRead, AsyncWriteExt, ReadBuf};
 use tokio::sync::RwLock;
-use tokio::time::Sleep;
+use tokio::time::Interval;
+use tokio_util::codec::{BytesCodec, FramedRead};
 
-use super::{BoxedImageStream, CacheStreamItem};
+use super::{BoxedImageStream, CacheStream, CacheStreamItem};
 
 /// Keeps track of files that are currently being written to.
 ///
@@ -36,15 +38,23 @@ static WRITING_STATUS: Lazy<RwLock<HashMap<PathBuf, Arc<CacheStatus>>>> =
     Lazy::new(|| RwLock::new(HashMap::new()));
 
 /// Tries to read from the file, returning a byte stream if it exists
-pub async fn read_file(path: &Path) -> Option<Result<FsStream, std::io::Error>> {
+pub async fn read_file(path: &Path) -> Option<Result<CacheStream, std::io::Error>> {
     if path.exists() {
-        let status = WRITING_STATUS
-            .read()
-            .await
-            .get(path)
-            .map_or_else(|| Arc::new(CacheStatus::done()), Arc::clone);
+        let status = WRITING_STATUS.read().await.get(path).map(Arc::clone);
 
-        Some(FsStream::new(path, status).await)
+        if let Some(status) = status {
+            Some(
+                ConcurrentFsStream::new(path, status)
+                    .await
+                    .map(CacheStream::Concurrent),
+            )
+        } else {
+            Some(
+                File::open(path)
+                    .await
+                    .map(|f| CacheStream::Completed(FramedRead::new(f, BytesCodec::new()))),
+            )
+        }
     } else {
         None
     }
@@ -55,11 +65,13 @@ pub async fn read_file(path: &Path) -> Option<Result<FsStream, std::io::Error>>
 pub async fn write_file(
     path: &Path,
     mut byte_stream: BoxedImageStream,
-) -> Result<FsStream, std::io::Error> {
+) -> Result<CacheStream, std::io::Error> {
     let done_writing_flag = Arc::new(CacheStatus::new());
 
     let mut file = {
         let mut write_lock = WRITING_STATUS.write().await;
+        let parent = path.parent().unwrap();
+        create_dir_all(parent).await?;
         let file = File::create(path).await?; // we need to make sure the file exists and is truncated.
         write_lock.insert(path.to_path_buf(), Arc::clone(&done_writing_flag));
         file
@@ -87,6 +99,7 @@ pub async fn write_file(
         } else {
             file.flush().await?;
             file.sync_all().await?; // we need metadata
+            debug!("writing to file done");
         }
 
         let mut write_lock = WRITING_STATUS.write().await;
@@ -103,21 +116,23 @@ pub async fn write_file(
         Ok::<_, std::io::Error>(())
     });
 
-    Ok(FsStream::new(path, done_writing_flag).await?)
+    Ok(CacheStream::Concurrent(
+        ConcurrentFsStream::new(path, done_writing_flag).await?,
+    ))
 }
 
-pub struct FsStream {
+pub struct ConcurrentFsStream {
     file: Pin<Box<File>>,
-    sleep: Pin<Box<Sleep>>,
+    sleep: Pin<Box<Interval>>,
     is_file_done_writing: Arc<CacheStatus>,
 }
 
-impl FsStream {
+impl ConcurrentFsStream {
     async fn new(path: &Path, is_done: Arc<CacheStatus>) -> Result<Self, std::io::Error> {
         Ok(Self {
             file: Box::pin(File::open(path).await?),
             // 0.5ms
-            sleep: Box::pin(tokio::time::sleep(Duration::from_micros(500))),
+            sleep: Box::pin(tokio::time::interval(Duration::from_micros(500))),
             is_file_done_writing: is_done,
         })
     }
@@ -135,25 +150,35 @@ impl Display for UpstreamError {
     }
 }
 
-impl Stream for FsStream {
+impl Stream for ConcurrentFsStream {
     type Item = CacheStreamItem;
 
     fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
         let status = self.is_file_done_writing.load();
 
-        let mut bytes = BytesMut::with_capacity(1460);
+        let mut bytes = [0; 1460].to_vec();
         let mut buffer = ReadBuf::new(&mut bytes);
         let polled_result = self.file.as_mut().poll_read(cx, &mut buffer);
-
-        match (status, buffer.filled().len()) {
+        let filled = buffer.filled().len();
+        match (status, filled) {
             // Prematurely reached EOF, schedule a poll in the future
             (WritingStatus::NotDone, 0) => {
-                let _ = self.sleep.as_mut().poll(cx);
+                let _ = self.sleep.as_mut().poll_tick(cx);
                 Poll::Pending
             }
             // We got an error, abort the read.
             (WritingStatus::Error, _) => Poll::Ready(Some(Err(UpstreamError))),
-            _ => polled_result.map(|_| Some(Ok(bytes.split().into()))),
+            _ => {
+                bytes.truncate(filled);
+                polled_result.map(|_| {
+                    if bytes.is_empty() {
+                        dbg!(line!());
+                        None
+                    } else {
+                        Some(Ok(bytes.into()))
+                    }
+                })
+            }
         }
     }
 }
@@ -173,11 +198,6 @@ impl CacheStatus {
         Self(AtomicU8::new(WritingStatus::NotDone as u8))
     }
 
-    #[inline]
-    const fn done() -> Self {
-        Self(AtomicU8::new(WritingStatus::Done as u8))
-    }
-
     #[inline]
     fn store(&self, status: WritingStatus) {
         self.0.store(status as u8, Ordering::Release);
@@ -189,6 +209,7 @@ impl CacheStatus {
     }
 }
 
+#[derive(Debug)]
 enum WritingStatus {
     NotDone = 0,
     Done,

src/cache/low_mem.rs

@@ -34,10 +34,9 @@ impl Cache for LowMemCache {
     ) -> Option<Result<(CacheStream, &ImageMetadata), CacheError>> {
         let metadata = self.on_disk.get(key)?;
         let path = self.disk_path.clone().join(PathBuf::from(key.clone()));
-        super::fs::read_file(&path).await.map(|res| {
-            res.map(|stream| (CacheStream::Fs(stream), metadata))
-                .map_err(Into::into)
-        })
+        super::fs::read_file(&path)
+            .await
+            .map(|res| res.map(|stream| (stream, metadata)).map_err(Into::into))
     }
 
     async fn put(
@@ -50,7 +49,6 @@ impl Cache for LowMemCache {
         self.on_disk.put(key.clone(), metadata);
         super::fs::write_file(&path, image)
             .await
-            .map(CacheStream::Fs)
             .map(move |stream| (stream, self.on_disk.get(&key).unwrap()))
             .map_err(Into::into)
     }

src/cache/mod.rs

@@ -8,7 +8,7 @@ use actix_web::http::HeaderValue;
 use async_trait::async_trait;
 use bytes::Bytes;
 use chrono::{DateTime, FixedOffset};
-use fs::FsStream;
+use fs::ConcurrentFsStream;
 use futures::{Stream, StreamExt};
 use log::debug;
 use thiserror::Error;
@@ -16,6 +16,8 @@ use thiserror::Error;
 pub use fs::UpstreamError;
 pub use generational::GenerationalCache;
 pub use low_mem::LowMemCache;
+use tokio::fs::File;
+use tokio_util::codec::{BytesCodec, FramedRead};
 
 mod fs;
 mod generational;
@@ -163,8 +165,9 @@ pub trait Cache: Send + Sync {
 }
 
 pub enum CacheStream {
-    Fs(FsStream),
+    Concurrent(ConcurrentFsStream),
     Memory(MemStream),
+    Completed(FramedRead<File, BytesCodec>),
 }
 
 impl From<CachedImage> for CacheStream {
@@ -180,8 +183,12 @@ impl Stream for CacheStream {
 
     fn poll_next(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
         match self.get_mut() {
-            Self::Fs(stream) => stream.poll_next_unpin(cx),
+            Self::Concurrent(stream) => stream.poll_next_unpin(cx),
             Self::Memory(stream) => stream.poll_next_unpin(cx),
+            Self::Completed(stream) => stream
+                .poll_next_unpin(cx)
+                .map_ok(|v| v.freeze())
+                .map_err(|_| UpstreamError),
         }
     }
 }
@@ -192,9 +199,12 @@ impl Stream for MemStream {
     type Item = CacheStreamItem;
 
     fn poll_next(mut self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Option<Self::Item>> {
-        let mut new_bytes = Bytes::new();
-        std::mem::swap(&mut self.0, &mut new_bytes);
-        Poll::Ready(Some(Ok(new_bytes)))
+        let new_bytes = self.0.split_to(1460);
+        if new_bytes.is_empty() {
+            Poll::Ready(None)
+        } else {
+            Poll::Ready(Some(Ok(new_bytes)))
+        }
     }
 }
 

src/config.rs

@@ -3,6 +3,7 @@ use std::path::PathBuf;
 use std::sync::atomic::AtomicBool;
 
 use clap::{crate_authors, crate_description, crate_version, Clap};
+use url::Url;
 
 // Validate tokens is an atomic because it's faster than locking on rwlock.
 pub static VALIDATE_TOKENS: AtomicBool = AtomicBool::new(false);
@@ -42,7 +43,20 @@ pub struct CliArgs {
         env = "LOW_MEMORY_MODE",
         takes_value = false
     )]
+    /// Changes the caching behavior to avoid buffering images in memory, and
+    /// instead use the filesystem as the buffer backing. This is useful for
+    /// clients in low (< 1GB) RAM environments.
     pub low_memory: bool,
+    /// Changes verbosity. Default verbosity is INFO, while increasing counts
+    /// of verbose flags increases to DEBUG and TRACE, respectively.
     #[clap(short, long, parse(from_occurrences))]
     pub verbose: usize,
+    /// Overrides the upstream URL to fetch images from. Don't use this unless
+    /// you know what you're dealing with.
+    #[clap(long)]
+    pub override_upstream: Option<Url>,
+    /// Disables token validation. Don't use this unless you know the
+    /// ramifications of this command.
+    #[clap(long)]
+    pub disable_token_validation: bool,
 }

src/main.rs

@@ -51,29 +51,6 @@ async fn main() -> Result<(), std::io::Error> {
     dotenv::dotenv().ok();
     let cli_args = CliArgs::parse();
 
-    println!(concat!(
-        env!("CARGO_PKG_NAME"),
-        " ",
-        env!("CARGO_PKG_VERSION"),
-        "  Copyright (C) 2021  ",
-        env!("CARGO_PKG_AUTHORS"),
-        "\n\n",
-        env!("CARGO_PKG_NAME"),
-        " is free software: you can redistribute it and/or modify\n\
-        it under the terms of the GNU General Public License as published by\n\
-        the Free Software Foundation, either version 3 of the License, or\n\
-        (at your option) any later version.\n\n",
-        env!("CARGO_PKG_NAME"),
-        " is distributed in the hope that it will be useful,\n\
-        but WITHOUT ANY WARRANTY; without even the implied warranty of\n\
-        MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the\n\
-        GNU General Public License for more details.\n\n\
-        You should have received a copy of the GNU General Public License\n\
-        along with ",
-        env!("CARGO_PKG_NAME"),
-        ". If not, see <https://www.gnu.org/licenses/>.\n"
-    ));
-
     let port = cli_args.port;
     let memory_max_size = cli_args.memory_quota.get();
     let disk_quota = cli_args.disk_quota;
@@ -88,6 +65,8 @@ async fn main() -> Result<(), std::io::Error> {
     .init()
     .unwrap();
 
+    print_preamble_and_warnings();
+
     let client_secret = if let Ok(v) = env::var("CLIENT_SECRET") {
         v
     } else {
@@ -111,13 +90,21 @@ async fn main() -> Result<(), std::io::Error> {
 
     // Set ctrl+c to send a stop message
     let running = Arc::new(AtomicBool::new(true));
-    let r = running.clone();
+    let running_1 = running.clone();
+    let system = System::current();
     ctrlc::set_handler(move || {
+        let system = &system;
         let client_secret = client_secret.clone();
+        let running_2 = Arc::clone(&running_1);
         System::new().block_on(async move {
-            send_stop(&client_secret).await;
+            if running_2.load(Ordering::SeqCst) {
+                send_stop(&client_secret).await;
+            } else {
+                warn!("Got second ctrl-c, forcefully exiting");
+                system.stop()
+            }
         });
-        r.store(false, Ordering::SeqCst);
+        running_1.store(false, Ordering::SeqCst);
     })
     .expect("Error setting Ctrl-C handler");
 
@@ -174,3 +161,28 @@ async fn main() -> Result<(), std::io::Error> {
 
     Ok(())
 }
+
+fn print_preamble_and_warnings() {
+    println!(concat!(
+        env!("CARGO_PKG_NAME"),
+        " ",
+        env!("CARGO_PKG_VERSION"),
+        "  Copyright (C) 2021  ",
+        env!("CARGO_PKG_AUTHORS"),
+        "\n\n",
+        env!("CARGO_PKG_NAME"),
+        " is free software: you can redistribute it and/or modify\n\
+        it under the terms of the GNU General Public License as published by\n\
+        the Free Software Foundation, either version 3 of the License, or\n\
+        (at your option) any later version.\n\n",
+        env!("CARGO_PKG_NAME"),
+        " is distributed in the hope that it will be useful,\n\
+        but WITHOUT ANY WARRANTY; without even the implied warranty of\n\
+        MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the\n\
+        GNU General Public License for more details.\n\n\
+        You should have received a copy of the GNU General Public License\n\
+        along with ",
+        env!("CARGO_PKG_NAME"),
+        ". If not, see <https://www.gnu.org/licenses/>.\n"
+    ));
+}

src/ping.rs

@@ -68,7 +68,7 @@ impl<'a> From<(&'a str, &CliArgs)> for Request<'a> {
 pub struct Response {
     pub image_server: Url,
     pub latest_build: usize,
-    pub url: String,
+    pub url: Url,
     pub token_key: Option<String>,
     pub compromised: bool,
     pub paused: bool,
@@ -145,8 +145,8 @@ impl std::fmt::Debug for Tls {
     }
 }
 
-pub async fn update_server_state(secret: &str, req: &CliArgs, data: &mut Arc<RwLockServerState>) {
-    let req = Request::from_config_and_state(secret, req, data);
+pub async fn update_server_state(secret: &str, cli: &CliArgs, data: &mut Arc<RwLockServerState>) {
+    let req = Request::from_config_and_state(secret, cli, data);
     let client = reqwest::Client::new();
     let resp = client.post(CONTROL_CENTER_PING_URL).json(&req).send().await;
     match resp {
@@ -154,7 +154,10 @@ pub async fn update_server_state(secret: &str, req: &CliArgs, data: &mut Arc<RwL
             Ok(resp) => {
                 let mut write_guard = data.0.write();
 
-                write_guard.image_server = resp.image_server;
+                if !write_guard.url_overridden && write_guard.image_server != resp.image_server {
+                    warn!("Ignoring new upstream url!");
+                    write_guard.image_server = resp.image_server;
+                }
 
                 if let Some(key) = resp.token_key {
                     if let Some(key) = base64::decode(&key)
@@ -167,7 +170,9 @@ pub async fn update_server_state(secret: &str, req: &CliArgs, data: &mut Arc<RwL
                     }
                 }
 
-                if VALIDATE_TOKENS.load(Ordering::Acquire) != resp.force_tokens {
+                if !cli.disable_token_validation
+                    && VALIDATE_TOKENS.load(Ordering::Acquire) != resp.force_tokens
+                {
                     if resp.force_tokens {
                         info!("Client received command to enforce token validity.");
                     } else {

src/routes.rs

@@ -11,7 +11,7 @@ use base64::DecodeError;
 use bytes::Bytes;
 use chrono::{DateTime, Utc};
 use futures::{Stream, TryStreamExt};
-use log::{error, info, warn};
+use log::{debug, error, info, warn};
 use parking_lot::Mutex;
 use serde::Deserialize;
 use sodiumoxide::crypto::box_::{open_precomputed, Nonce, PrecomputedKey, NONCEBYTES};
@@ -76,6 +76,7 @@ async fn token_data_saver(
             return ServerResponse::TokenValidationError(e);
         }
     }
+
     fetch_image(state, cache, chapter_hash, file_name, true).await
 }
 
@@ -86,7 +87,13 @@ pub async fn default(state: Data<RwLockServerState>, req: HttpRequest) -> impl R
         req.path().chars().skip(1).collect::<String>()
     );
     info!("Got unknown path, just proxying: {}", path);
-    let resp = reqwest::get(path).await.unwrap();
+    let resp = match reqwest::get(path).await {
+        Ok(resp) => resp,
+        Err(e) => {
+            error!("{}", e);
+            return ServerResponse::HttpResponse(HttpResponse::BadGateway().finish());
+        }
+    };
     let content_type = resp.headers().get(CONTENT_TYPE);
     let mut resp_builder = HttpResponseBuilder::new(resp.status());
     if let Some(content_type) = content_type {
@@ -153,6 +160,8 @@ fn validate_token(
         return Err(TokenValidationError::InvalidChapterHash);
     }
 
+    debug!("Token validated!");
+
     Ok(())
 }
 
@@ -194,15 +203,15 @@ async fn fetch_image(
         reqwest::get(format!(
             "{}/data-saver/{}/{}",
             state.0.read().image_server,
-            &key.1,
-            &key.2
+            &key.0,
+            &key.1
         ))
     } else {
         reqwest::get(format!(
             "{}/data/{}/{}",
             state.0.read().image_server,
-            &key.1,
-            &key.2
+            &key.0,
+            &key.1
         ))
     }
     .await;
@@ -214,6 +223,7 @@ async fn fetch_image(
             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.",
@@ -241,6 +251,9 @@ async fn fetch_image(
             };
 
             let body = resp.bytes_stream().map_err(|e| e.into());
+
+            debug!("Inserting into cache");
+
             let metadata = ImageMetadata::new(content_type, length, last_mod).unwrap();
             let (stream, metadata) = {
                 match cache.lock().put(key, Box::new(body), metadata).await {
@@ -254,6 +267,8 @@ async fn fetch_image(
                 }
             };
 
+            debug!("Done putting into cache");
+
             return construct_response(stream, &metadata);
         }
         Err(e) => {
@@ -269,6 +284,8 @@ fn construct_response(
     data: impl Stream<Item = Result<Bytes, UpstreamError>> + Unpin + 'static,
     metadata: &ImageMetadata,
 ) -> ServerResponse {
+    debug!("Constructing response");
+
     let mut resp = HttpResponse::Ok();
     if let Some(content_type) = metadata.content_type {
         resp.append_header((CONTENT_TYPE, content_type.as_ref()));

src/state.rs

@@ -13,7 +13,8 @@ pub struct ServerState {
     pub precomputed_key: PrecomputedKey,
     pub image_server: Url,
     pub tls_config: Tls,
-    pub url: String,
+    pub url: Url,
+    pub url_overridden: bool,
     pub log_state: LogState,
 }
 
@@ -36,7 +37,7 @@ impl ServerState {
 
         match resp {
             Ok(resp) => match resp.json::<Response>().await {
-                Ok(resp) => {
+                Ok(mut resp) => {
                     let key = resp
                         .token_key
                         .and_then(|key| {
@@ -60,21 +61,31 @@ impl ServerState {
                         warn!("Control center has paused this node!");
                     }
 
-                    info!("This client's URL has been set to {}", resp.url);
-
-                    if resp.force_tokens {
-                        info!("This client will validate tokens.");
+                    if let Some(ref override_url) = config.override_upstream {
+                        resp.image_server = override_url.clone();
+                        warn!("Upstream URL overridden to: {}", resp.image_server);
                     } else {
-                        info!("This client will not validate tokens.");
                     }
 
-                    VALIDATE_TOKENS.store(resp.force_tokens, Ordering::Release);
+                    info!("This client's URL has been set to {}", resp.url);
+
+                    if config.disable_token_validation {
+                        warn!("Token validation is explicitly disabled!");
+                    } else {
+                        if resp.force_tokens {
+                            info!("This client will validate tokens.");
+                        } else {
+                            info!("This client will not validate tokens.");
+                        }
+                        VALIDATE_TOKENS.store(resp.force_tokens, Ordering::Release);
+                    }
 
                     Ok(Self {
                         precomputed_key: key,
                         image_server: resp.image_server,
                         tls_config: resp.tls.unwrap(),
                         url: resp.url,
+                        url_overridden: config.override_upstream.is_some(),
                         log_state: LogState {
                             was_paused_before: resp.paused,
                         },