feat: add configuration through file

A file named `config.toml` can now be used to load the address, port,
and some websocket configuration settings.

Fixes https://todo.sr.ht/~gheartsfield/nostr-rs-relay/3

Cargo.lock

@@ -22,6 +22,12 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "arrayvec"
+version = "0.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "23b62fc65de8e4e7f52534fb52b0f3ed04746ae267519eef2a83941e8085068b"
+
 [[package]]
 name = "atty"
 version = "0.2.14"
@@ -57,7 +63,7 @@ version = "0.9.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7ce18265ec2324ad075345d5814fbeed4f41f0a660055dc78840b74d19b874b1"
 dependencies = [
- "serde",
+ "serde 1.0.131",
 ]
 
 [[package]]
@@ -108,6 +114,22 @@ dependencies = [
  "bitflags",
 ]
 
+[[package]]
+name = "config"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1b1b9d958c2b1368a663f05538fc1b5975adce1e19f435acceae987aceeeb369"
+dependencies = [
+ "lazy_static",
+ "nom",
+ "rust-ini",
+ "serde 1.0.131",
+ "serde-hjson",
+ "serde_json",
+ "toml",
+ "yaml-rust",
+]
+
 [[package]]
 name = "cpufeatures"
 version = "0.2.1"
@@ -365,6 +387,25 @@ version = "0.4.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b71991ff56294aa922b450139ee08b3bfc70982c6b2c7562771375cf73542dd4"
 
+[[package]]
+name = "lazy_static"
+version = "1.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
+
+[[package]]
+name = "lexical-core"
+version = "0.7.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6607c62aa161d23d17a9072cc5da0be67cdfc89d3afb1e8d9c842bebc2525ffe"
+dependencies = [
+ "arrayvec",
+ "bitflags",
+ "cfg-if",
+ "ryu",
+ "static_assertions",
+]
+
 [[package]]
 name = "libc"
 version = "0.2.111"
@@ -381,6 +422,12 @@ dependencies = [
  "vcpkg",
 ]
 
+[[package]]
+name = "linked-hash-map"
+version = "0.5.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7fb9b38af92608140b86b693604b9ffcc5824240a484d1ecd4795bacb2fe88f3"
+
 [[package]]
 name = "lock_api"
 version = "0.4.5"
@@ -433,19 +480,32 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "nom"
+version = "5.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ffb4262d26ed83a1c0a33a38fe2bb15797329c85770da05e6b828ddb782627af"
+dependencies = [
+ "lexical-core",
+ "memchr",
+ "version_check",
+]
+
 [[package]]
 name = "nostr-rs-relay"
 version = "0.1.6"
 dependencies = [
  "bitcoin_hashes",
+ "config",
  "env_logger",
  "futures",
  "futures-util",
  "hex",
+ "lazy_static",
  "log",
  "rusqlite",
  "secp256k1",
- "serde",
+ "serde 1.0.131",
  "serde_json",
  "thiserror",
  "tokio",
@@ -463,6 +523,24 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "num-traits"
+version = "0.1.43"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "92e5113e9fd4cc14ded8e499429f396a20f98c772a47cc8622a736e1ec843c31"
+dependencies = [
+ "num-traits 0.2.14",
+]
+
+[[package]]
+name = "num-traits"
+version = "0.2.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9a64b1ec5cda2586e284722486d802acf1f7dbdc623e2bfc57e65ca1cd099290"
+dependencies = [
+ "autocfg 1.0.1",
+]
+
 [[package]]
 name = "num_cpus"
 version = "1.13.0"
@@ -754,6 +832,12 @@ dependencies = [
  "smallvec",
 ]
 
+[[package]]
+name = "rust-ini"
+version = "0.13.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3e52c148ef37f8c375d49d5a73aa70713125b7f19095948a923f80afdeb22ec2"
+
 [[package]]
 name = "ryu"
 version = "1.0.7"
@@ -775,7 +859,7 @@ dependencies = [
  "bitcoin_hashes",
  "rand 0.6.5",
  "secp256k1-sys",
- "serde",
+ "serde 1.0.131",
 ]
 
 [[package]]
@@ -787,6 +871,12 @@ dependencies = [
  "cc",
 ]
 
+[[package]]
+name = "serde"
+version = "0.8.23"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9dad3f759919b92c3068c696c15c3d17238234498bbdcc80f2c469606f948ac8"
+
 [[package]]
 name = "serde"
 version = "1.0.131"
@@ -796,6 +886,18 @@ dependencies = [
  "serde_derive",
 ]
 
+[[package]]
+name = "serde-hjson"
+version = "0.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6a3a4e0ea8a88553209f6cc6cfe8724ecad22e1acf372793c27d995290fe74f8"
+dependencies = [
+ "lazy_static",
+ "num-traits 0.1.43",
+ "regex",
+ "serde 0.8.23",
+]
+
 [[package]]
 name = "serde_derive"
 version = "1.0.131"
@@ -815,7 +917,7 @@ checksum = "d0ffa0837f2dfa6fb90868c2b5468cad482e175f7dad97e7421951e663f2b527"
 dependencies = [
  "itoa",
  "ryu",
- "serde",
+ "serde 1.0.131",
 ]
 
 [[package]]
@@ -852,6 +954,12 @@ version = "1.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1ecab6c735a6bb4139c0caafd0cc3635748bbb3acf4550e8138122099251f309"
 
+[[package]]
+name = "static_assertions"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a2eb9349b6444b326872e140eb1cf5e7c522154d69e7a0ffb0fb81c06b37543f"
+
 [[package]]
 name = "syn"
 version = "1.0.82"
@@ -950,6 +1058,15 @@ dependencies = [
  "tungstenite",
 ]
 
+[[package]]
+name = "toml"
+version = "0.5.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a31142970826733df8241ef35dc040ef98c679ab14d7c3e54d827099b3acecaa"
+dependencies = [
+ "serde 1.0.131",
+]
+
 [[package]]
 name = "tungstenite"
 version = "0.16.0"
@@ -1071,3 +1188,12 @@ name = "winapi-x86_64-pc-windows-gnu"
 version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
+
+[[package]]
+name = "yaml-rust"
+version = "0.4.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "56c1936c4cc7a1c9ab21a1ebb602eb942ba868cbd44a99cb7cdc5892335e1c85"
+dependencies = [
+ "linked-hash-map",
+]

Cargo.toml

@@ -13,10 +13,11 @@ tokio-tungstenite = "^0.16"
 tungstenite = "^0.16"
 thiserror = "^1"
 uuid = { version = "^0.8", features = ["v4"] }
-
+config = { version = "0.11", features = ["toml"] }
 bitcoin_hashes = { version = "^0.9", features = ["serde"] }
 secp256k1 = { version = "^0.20", features = ["rand", "rand-std", "serde", "bitcoin_hashes"] }
 serde = { version = "^1.0", features = ["derive"] }
 serde_json = "^1.0"
 hex = "^0.4"
 rusqlite = "^0.26"
+lazy_static = "^1.4"

src/config.rs

@@ -0,0 +1,81 @@
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Serialize, Deserialize)]
+#[allow(unused)]
+pub struct Network {
+    pub port: u16,
+    pub address: String,
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+#[allow(unused)]
+pub struct Retention {
+    // TODO: implement
+    pub max_events: Option<usize>,        // max events
+    pub max_bytes: Option<usize>,         // max size
+    pub persist_days: Option<usize>,      // oldest message
+    pub whitelist_addresses: Vec<String>, // whitelisted addresses (never delete)
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+#[allow(unused)]
+pub struct Limits {
+    pub messages_per_sec: Option<usize>, // Artificially slow down event writing to limit disk consumption
+    pub max_event_bytes: Option<usize>,
+    pub max_ws_message_bytes: Option<usize>,
+    pub max_ws_frame_bytes: Option<usize>,
+    pub broadcast_buffer: usize, // events to buffer for subscribers (prevents slow readers from consuming memory)
+    pub event_persist_buffer: usize, // events to buffer for database commits (block senders if database writes are too slow)
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+#[allow(unused)]
+pub struct Settings {
+    pub network: Network,
+    pub limits: Limits,
+    pub retention: Retention,
+}
+
+impl Settings {
+    pub fn new() -> Self {
+        let d = Self::default();
+        // attempt to construct settings with file
+        Self::new_from_default(&d).unwrap_or(d)
+    }
+
+    fn new_from_default(default: &Settings) -> Result<Self, config::ConfigError> {
+        let config: config::Config = config::Config::new();
+        let settings: Settings = config
+            // use defaults
+            .with_merged(config::Config::try_from(default).unwrap())?
+            // override with file contents
+            .with_merged(config::File::with_name("config"))?
+            .try_into()?;
+        Ok(settings)
+    }
+}
+
+impl Default for Settings {
+    fn default() -> Self {
+        Settings {
+            network: Network {
+                port: 8080,
+                address: "0.0.0.0".to_owned(),
+            },
+            limits: Limits {
+                messages_per_sec: None,
+                max_event_bytes: Some(2 << 17),      // 128K
+                max_ws_message_bytes: Some(2 << 17), // 128K
+                max_ws_frame_bytes: Some(2 << 17),   // 128K
+                broadcast_buffer: 4096,
+                event_persist_buffer: 16,
+            },
+            retention: Retention {
+                max_events: None,            // max events
+                max_bytes: None,             // max size
+                persist_days: None,          // oldest message
+                whitelist_addresses: vec![], // whitelisted addresses (never delete)
+            },
+        }
+    }
+}

src/error.rs

@@ -34,6 +34,8 @@ pub enum Error {
     CommandUnknownError,
     #[error("SQL error")]
     SqlError(rusqlite::Error),
+    #[error("Config error")]
+    ConfigError(config::ConfigError),
 }
 
 impl From<rusqlite::Error> for Error {
@@ -56,3 +58,10 @@ impl From<WsError> for Error {
         Error::WebsocketError(r)
     }
 }
+
+impl From<config::ConfigError> for Error {
+    /// Wrap Config error
+    fn from(r: config::ConfigError) -> Self {
+        Error::ConfigError(r)
+    }
+}

src/lib.rs

@@ -1,4 +1,5 @@
 pub mod close;
+pub mod config;
 pub mod conn;
 pub mod db;
 pub mod error;

src/main.rs

@@ -1,8 +1,10 @@
 //! Server process
 use futures::SinkExt;
 use futures::StreamExt;
+use lazy_static::lazy_static;
 use log::*;
 use nostr_rs_relay::close::Close;
+use nostr_rs_relay::config;
 use nostr_rs_relay::conn;
 use nostr_rs_relay::db;
 use nostr_rs_relay::error::{Error, Result};
@@ -11,7 +13,7 @@ use nostr_rs_relay::protostream;
 use nostr_rs_relay::protostream::NostrMessage::*;
 use nostr_rs_relay::protostream::NostrResponse::*;
 use std::collections::HashMap;
-use std::env;
+use std::sync::RwLock;
 use tokio::net::{TcpListener, TcpStream};
 use tokio::runtime::Builder;
 use tokio::sync::broadcast;
@@ -19,14 +21,24 @@ use tokio::sync::broadcast::{Receiver, Sender};
 use tokio::sync::mpsc;
 use tokio::sync::oneshot;
 use tungstenite::protocol::WebSocketConfig;
+// initialize a singleton default configuration
+lazy_static! {
+    static ref SETTINGS: RwLock<config::Settings> = RwLock::new(config::Settings::default());
+}
 
 /// Start running a Nostr relay server.
 fn main() -> Result<(), Error> {
-    // setup logger and environment
+    // setup logger
     let _ = env_logger::try_init();
-    let addr = env::args()
+    {
-        .nth(1)
+        let mut settings = SETTINGS.write().unwrap();
-        .unwrap_or_else(|| "0.0.0.0:8080".to_string());
+        // replace default settings with those read from config.toml
+        let c = config::Settings::new();
+        debug!("using settings: {:?}", c);
+        *settings = c;
+    }
+    let config = SETTINGS.read().unwrap();
+    let addr = format!("{}:{}", config.network.address.trim(), config.network.port);
     // configure tokio runtime
     let rt = Builder::new_multi_thread()
         .enable_all()
@@ -35,16 +47,17 @@ fn main() -> Result<(), Error> {
         .unwrap();
     // start tokio
     rt.block_on(async {
+        let settings = SETTINGS.read().unwrap();
         let listener = TcpListener::bind(&addr).await.expect("Failed to bind");
         info!("listening on: {}", addr);
         // all client-submitted valid events are broadcast to every
         // other client on this channel.  This should be large enough
         // to accomodate slower readers (messages are dropped if
         // clients can not keep up).
-        let (bcast_tx, _) = broadcast::channel::<Event>(4096);
+        let (bcast_tx, _) = broadcast::channel::<Event>(settings.limits.broadcast_buffer);
         // validated events that need to be persisted are sent to the
         // database on via this channel.
-        let (event_tx, event_rx) = mpsc::channel::<Event>(16);
+        let (event_tx, event_rx) = mpsc::channel::<Event>(settings.limits.event_persist_buffer);
         // start the database writer thread.  Give it a channel for
         // writing events, and for publishing events that have been
         // written (to all connected clients).
@@ -94,13 +107,12 @@ async fn nostr_server(
 ) {
     // get a broadcast channel for clients to communicate on
     let mut bcast_rx = broadcast.subscribe();
-    // websocket configuration / limits
+    let mut config = WebSocketConfig::default();
-    let config = WebSocketConfig {
+    {
-        max_send_queue: None,
+        let settings = SETTINGS.read().unwrap();
-        max_message_size: Some(2 << 19), // 512K
+        config.max_message_size = settings.limits.max_ws_message_bytes;
-        max_frame_size: Some(2 << 19),   // 512k
+        config.max_frame_size = settings.limits.max_ws_frame_bytes;
-        accept_unmasked_frames: false,   // follow the spec
+    }
-    };
     // upgrade the TCP connection to WebSocket
     let conn = tokio_tungstenite::accept_async_with_config(stream, Some(config)).await;
     let ws_stream = conn.expect("websocket handshake error");