Add rate limiting functionality

backend/Cargo.lock

@@ -604,7 +604,9 @@ dependencies = [
  "serde_json",
  "sql-adaptor",
  "tokio",
+ "tower",
  "tower-http",
+ "tower_governor",
  "tracing",
  "tracing-subscriber",
 ]
@@ -702,6 +704,19 @@ dependencies = [
  "syn 2.0.15",
 ]
 
+[[package]]
+name = "dashmap"
+version = "5.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "907076dfda823b0b36d2a1bb5f90c96660a5bbcd7729e10727f07858f22c4edc"
+dependencies = [
+ "cfg-if",
+ "hashbrown 0.12.3",
+ "lock_api",
+ "once_cell",
+ "parking_lot_core 0.9.7",
+]
+
 [[package]]
 name = "der"
 version = "0.5.1"
@@ -840,6 +855,16 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "forwarded-header-value"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8835f84f38484cc86f110a805655697908257fb9a7af005234060891557198e9"
+dependencies = [
+ "nonempty",
+ "thiserror",
+]
+
 [[package]]
 name = "futures"
 version = "0.3.28"
@@ -848,6 +873,7 @@ checksum = "23342abe12aba583913b2e62f22225ff9c950774065e4bfb61a19cd9770fec40"
 dependencies = [
  "futures-channel",
  "futures-core",
+ "futures-executor",
  "futures-io",
  "futures-sink",
  "futures-task",
@@ -889,7 +915,7 @@ checksum = "a604f7a68fbf8103337523b1fadc8ade7361ee3f112f7c680ad179651616aed5"
 dependencies = [
  "futures-core",
  "lock_api",
- "parking_lot",
+ "parking_lot 0.11.2",
 ]
 
 [[package]]
@@ -913,6 +939,17 @@ dependencies = [
  "waker-fn",
 ]
 
+[[package]]
+name = "futures-macro"
+version = "0.3.28"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "89ca545a94061b6365f2c7355b4b32bd20df3ff95f02da9329b34ccc3bd6ee72"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.15",
+]
+
 [[package]]
 name = "futures-sink"
 version = "0.3.28"
@@ -925,6 +962,12 @@ version = "0.3.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "76d3d132be6c0e6aa1534069c705a74a5997a356c0dc2f86a47765e5617c5b65"
 
+[[package]]
+name = "futures-timer"
+version = "3.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e64b03909df88034c26dc1547e8970b91f98bdb65165d6a4e9110d94263dbb2c"
+
 [[package]]
 name = "futures-util"
 version = "0.3.28"
@@ -934,6 +977,7 @@ dependencies = [
  "futures-channel",
  "futures-core",
  "futures-io",
+ "futures-macro",
  "futures-sink",
  "futures-task",
  "memchr",
@@ -975,6 +1019,24 @@ dependencies = [
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "governor"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c390a940a5d157878dd057c78680a33ce3415bcd05b4799509ea44210914b4d5"
+dependencies = [
+ "cfg-if",
+ "dashmap",
+ "futures",
+ "futures-timer",
+ "no-std-compat",
+ "nonzero_ext",
+ "parking_lot 0.12.1",
+ "quanta",
+ "rand",
+ "smallvec",
+]
+
 [[package]]
 name = "hashbrown"
 version = "0.12.3"
@@ -1295,6 +1357,15 @@ dependencies = [
  "value-bag",
 ]
 
+[[package]]
+name = "mach"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b823e83b2affd8f40a9ee8c29dbc56404c1e34cd2710921f2801e2cf29527afa"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "matchers"
 version = "0.1.0"
@@ -1367,6 +1438,12 @@ dependencies = [
  "tempfile",
 ]
 
+[[package]]
+name = "no-std-compat"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b93853da6d84c2e3c7d730d6473e8817692dd89be387eb01b94d7f108ecb5b8c"
+
 [[package]]
 name = "nom"
 version = "7.1.3"
@@ -1377,6 +1454,18 @@ dependencies = [
  "minimal-lexical",
 ]
 
+[[package]]
+name = "nonempty"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e9e591e719385e6ebaeb5ce5d3887f7d5676fceca6411d1925ccc95745f3d6f7"
+
+[[package]]
+name = "nonzero_ext"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "38bf9645c8b145698bb0b18a4637dcacbc421ea49bef2317e4fd8065a387cf21"
+
 [[package]]
 name = "nu-ansi-term"
 version = "0.46.0"
@@ -1555,7 +1644,17 @@ checksum = "7d17b78036a60663b797adeaee46f5c9dfebb86948d1255007a1d6be0271ff99"
 dependencies = [
  "instant",
  "lock_api",
- "parking_lot_core",
+ "parking_lot_core 0.8.6",
+]
+
+[[package]]
+name = "parking_lot"
+version = "0.12.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3742b2c103b9f06bc9fff0a37ff4912935851bee6d36f3c02bcc755bcfec228f"
+dependencies = [
+ "lock_api",
+ "parking_lot_core 0.9.7",
 ]
 
 [[package]]
@@ -1572,6 +1671,19 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "parking_lot_core"
+version = "0.9.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9069cbb9f99e3a5083476ccb29ceb1de18b9118cafa53e90c9551235de2b9521"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "redox_syscall 0.2.16",
+ "smallvec",
+ "windows-sys 0.45.0",
+]
+
 [[package]]
 name = "paste"
 version = "1.0.12"
@@ -1743,6 +1855,22 @@ version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e9e1dcb320d6839f6edb64f7a4a59d39b30480d4d1765b56873f7c858538a5fe"
 
+[[package]]
+name = "quanta"
+version = "0.9.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "20afe714292d5e879d8b12740aa223c6a88f118af41870e8b6196e39a02238a8"
+dependencies = [
+ "crossbeam-utils",
+ "libc",
+ "mach",
+ "once_cell",
+ "raw-cpuid",
+ "wasi 0.10.0+wasi-snapshot-preview1",
+ "web-sys",
+ "winapi",
+]
+
 [[package]]
 name = "quote"
 version = "1.0.27"
@@ -1782,6 +1910,15 @@ dependencies = [
  "getrandom",
 ]
 
+[[package]]
+name = "raw-cpuid"
+version = "10.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6c297679cb867470fa8c9f67dbba74a78d78e3e98d7cf2b08d6d71540f797332"
+dependencies = [
+ "bitflags",
+]
+
 [[package]]
 name = "redox_syscall"
 version = "0.2.16"
@@ -2237,6 +2374,15 @@ dependencies = [
  "lazy_static",
 ]
 
+[[package]]
+name = "signal-hook-registry"
+version = "1.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d8229b473baa5980ac72ef434c4415e70c4b5e71b423043adb4ba059f89c99a1"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "simdutf8"
 version = "0.1.4"
@@ -2586,7 +2732,9 @@ dependencies = [
  "libc",
  "mio",
  "num_cpus",
+ "parking_lot 0.12.1",
  "pin-project-lite",
+ "signal-hook-registry",
  "socket2",
  "tokio-macros",
  "windows-sys 0.48.0",
@@ -2665,6 +2813,7 @@ dependencies = [
  "pin-project-lite",
  "tower-layer",
  "tower-service",
+ "tracing",
 ]
 
 [[package]]
@@ -2679,6 +2828,26 @@ version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b6bc1c9ce2b5135ac7f93c72918fc37feb872bdc6a5533a8b85eb4b86bfdae52"
 
+[[package]]
+name = "tower_governor"
+version = "0.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2c6be418f6d18863291f0a7fa1da1de71495a19a54b5fb44969136f731a47e86"
+dependencies = [
+ "axum",
+ "forwarded-header-value",
+ "futures",
+ "futures-core",
+ "governor",
+ "http",
+ "pin-project",
+ "thiserror",
+ "tokio",
+ "tower",
+ "tower-layer",
+ "tracing",
+]
+
 [[package]]
 name = "tracing"
 version = "0.1.37"

backend/Cargo.toml

@@ -21,4 +21,6 @@ tracing = "0.1.37"
 tracing-subscriber = "0.3.17"
 chrono = "0.4.24"
 bcrypt = "0.14.0"
-tower-http = { version = "0.4.0", features = ["cors"] }
+tower-http = { version = "0.4.0", features = ["cors", "trace"] }
+tower_governor = "0.0.4"
+tower = "0.4.13"

backend/src/main.rs

@@ -1,15 +1,18 @@
 use std::{env, net::SocketAddr, sync::Arc};
 
 use axum::{
+    error_handling::HandleErrorLayer,
     extract,
     http::{HeaderValue, Method},
     routing::{get, patch, post},
-    Router, Server,
+    BoxError, Router, Server,
 };
 use routes::*;
 use sql_adaptor::SqlAdaptor;
 use tokio::sync::Mutex;
-use tower_http::cors::CorsLayer;
+use tower::ServiceBuilder;
+use tower_governor::{errors::display_error, governor::GovernorConfigBuilder, GovernorLayer};
+use tower_http::{cors::CorsLayer, trace::TraceLayer};
 
 mod errors;
 mod payloads;
@@ -32,6 +35,7 @@ async fn main() {
         adaptor: SqlAdaptor::new().await,
     }));
 
+    // CORS configuration
     let cors = CorsLayer::new()
         .allow_methods([Method::GET, Method::POST, Method::PATCH])
         .allow_origin(
@@ -44,6 +48,19 @@ async fn main() {
             .unwrap(),
         );
 
+    // Rate limiting configuration (using tower_governor)
+    // From the docs: Allows bursts with up to eight requests and replenishes
+    // one element after 500ms, based on peer IP.
+    let governor_config = Box::new(GovernorConfigBuilder::default().finish().unwrap());
+    let rate_limit = ServiceBuilder::new()
+        // Handle errors from governor and convert into HTTP responses
+        .layer(HandleErrorLayer::new(|e: BoxError| async move {
+            display_error(e)
+        }))
+        .layer(GovernorLayer {
+            config: Box::leak(governor_config),
+        });
+
     let app = Router::new()
         .route("/", get(get_root))
         .route("/stats", get(get_stats))
@@ -53,7 +70,9 @@ async fn main() {
         .route("/event/:event_id/people/:person_name", get(get_person))
         .route("/event/:event_id/people/:person_name", patch(update_person))
         .with_state(shared_state)
-        .layer(cors);
+        .layer(cors)
+        .layer(rate_limit)
+        .layer(TraceLayer::new_for_http());
 
     let addr = SocketAddr::from(([127, 0, 0, 1], 3000));
 
@@ -67,7 +86,7 @@ async fn main() {
         }
     );
     Server::bind(&addr)
-        .serve(app.into_make_service())
+        .serve(app.into_make_service_with_connect_info::<SocketAddr>())
         .await
         .unwrap();
 }