From b618ff1b1cd3ea30d2705b21db31be042d89309f Mon Sep 17 00:00:00 2001
From: Christopher Kolstad <chriswk@getunleash.ai>
Date: Fri, 27 Jan 2023 16:12:19 +0100
Subject: [PATCH] task: added etag middleware (#22)

---
 Cargo.lock         | 55 ++++++++++++++++++++++++++++++++++++++++++++--
 server/Cargo.toml  |  2 ++
 server/src/main.rs |  2 ++
 3 files changed, 57 insertions(+), 2 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 4c52c22e..ae3d3b3f 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -46,7 +46,7 @@ dependencies = [
  "actix-tls",
  "actix-utils",
  "ahash",
- "base64",
+ "base64 0.21.0",
  "bitflags",
  "brotli",
  "bytes",
@@ -84,6 +84,19 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "actix-middleware-etag"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "44ad18cee06216ed944a2bf2d0b9565a879a89ea52d738f8dd8173c8910cd768"
+dependencies = [
+ "actix-service",
+ "actix-web",
+ "base64 0.13.1",
+ "futures",
+ "xxhash-rust",
+]
+
 [[package]]
 name = "actix-router"
 version = "0.5.1"
@@ -327,6 +340,12 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d468802bab17cbc0cc575e9b053f41e72aa36bfa6b7f55e3529ffa43161b97fa"
 
+[[package]]
+name = "base64"
+version = "0.13.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9e1b586273c5702936fe7b7d6896644d8be71e6314cfe09d3167c95f712589e8"
+
 [[package]]
 name = "base64"
 version = "0.21.0"
@@ -817,6 +836,21 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "futures"
+version = "0.3.25"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "38390104763dc37a5145a53c29c63c1290b5d316d6086ec32c293f6736051bb0"
+dependencies = [
+ "futures-channel",
+ "futures-core",
+ "futures-executor",
+ "futures-io",
+ "futures-sink",
+ "futures-task",
+ "futures-util",
+]
+
 [[package]]
 name = "futures-channel"
 version = "0.3.25"
@@ -824,6 +858,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "52ba265a92256105f45b719605a571ffe2d1f0fea3807304b522c1d778f79eed"
 dependencies = [
  "futures-core",
+ "futures-sink",
 ]
 
 [[package]]
@@ -843,6 +878,12 @@ dependencies = [
  "futures-util",
 ]
 
+[[package]]
+name = "futures-io"
+version = "0.3.25"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "00f5fb52a06bdcadeb54e8d3671f8888a39697dcb0b81b23b55174030427f4eb"
+
 [[package]]
 name = "futures-macro"
 version = "0.3.25"
@@ -872,10 +913,13 @@ version = "0.3.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "197676987abd2f9cadff84926f410af1c183608d36641465df73ae8211dc65d6"
 dependencies = [
+ "futures-channel",
  "futures-core",
+ "futures-io",
  "futures-macro",
  "futures-sink",
  "futures-task",
+ "memchr",
  "pin-project-lite",
  "pin-utils",
  "slab",
@@ -1685,7 +1729,7 @@ version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d194b56d58803a43635bdc398cd17e383d6f71f9182b9a192c127ca42494a59b"
 dependencies = [
- "base64",
+ "base64 0.21.0",
 ]
 
 [[package]]
@@ -2229,6 +2273,7 @@ name = "unleash-edge"
 version = "0.0.0"
 dependencies = [
  "actix-cors",
+ "actix-middleware-etag",
  "actix-tls",
  "actix-web",
  "actix-web-opentelemetry",
@@ -2510,6 +2555,12 @@ version = "0.42.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "447660ad36a13288b1db4d4248e857b510e8c3a225c822ba4fb748c0aafecffd"
 
+[[package]]
+name = "xxhash-rust"
+version = "0.8.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "735a71d46c4d68d71d4b24d03fdc2b98e38cea81730595801db779c04fe80d70"
+
 [[package]]
 name = "zstd"
 version = "0.12.2+zstd.1.5.2"
diff --git a/server/Cargo.toml b/server/Cargo.toml
index 86d01e25..93b6ee92 100644
--- a/server/Cargo.toml
+++ b/server/Cargo.toml
@@ -10,9 +10,11 @@ homepage = "https://github.com/Unleash/unleash-edge"
 
 [dependencies]
 actix-cors = "0.6.4"
+actix-middleware-etag = "0.1.1"
 actix-tls = { version = "3.0.3", features = ["rustls"] }
 actix-web = { version = "4.3.0", features = ["rustls"] }
 actix-web-opentelemetry = { version = "0.13.0", features = ["metrics", "metrics-prometheus"] }
+
 anyhow = "1.0.68"
 chrono = { version = "0.4.23", features = ["serde"] }
 clap = { version = "4.1.4", features = ["derive", "env"] }
diff --git a/server/src/main.rs b/server/src/main.rs
index 72ff49b0..a479a511 100644
--- a/server/src/main.rs
+++ b/server/src/main.rs
@@ -3,6 +3,7 @@ use std::sync::Arc;
 use crate::cli::EdgeMode;
 use crate::offline_provider::OfflineProvider;
 use actix_cors::Cors;
+use actix_middleware_etag::Etag;
 use actix_web::{http, middleware, web, App, HttpServer};
 use actix_web_opentelemetry::RequestTracing;
 use clap::Parser;
@@ -45,6 +46,7 @@ async fn main() -> Result<(), anyhow::Error> {
             .allowed_header(http::header::CONTENT_TYPE);
         App::new()
             .app_data(client_provider_data)
+            .wrap(Etag::default())
             .wrap(cors_middleware)
             .wrap(RequestTracing::new())
             .wrap(request_metrics.clone())