Dev/header to metadata

.gitignore

@@ -1,3 +1,5 @@
 .vscode/
 envoy-rate-limit-header/target/
-mock-backend/node_modules/
+mock-backend/node_modules/
+header-to-metadata/add-header-filter/target/
+header-to-metadata/metadata-filter/target/

header-to-metadata/add-header-filter/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "add-header-filter"
+version = "0.1.0"
+authors = ["Lahiru Udayanga <[email protected]>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[lib]
+path = "src/lib.rs"
+crate-type = ["cdylib"]
+
+[dependencies]
+proxy-wasm = "0.1.3"
+log = "0.4.14"
+wasm-bindgen = "0.2.74"

header-to-metadata/add-header-filter/Makefile

@@ -0,0 +1,9 @@
+build: add_header_filter.wasm
+
+add_header_filter.wasm:
+	cargo build --target wasm32-unknown-unknown --release
+	cp target/wasm32-unknown-unknown/release/add_header_filter.wasm ../build/add_header_filter.wasm
+
+.PHONY: clean
+clean:
+	rm ../build/add_header_filter.wasm || true

header-to-metadata/add-header-filter/src/lib.rs

@@ -0,0 +1,43 @@
+use log::info;
+use proxy_wasm::traits::*;
+use proxy_wasm::types::*;
+
+#[no_mangle]
+pub fn _start() {
+    proxy_wasm::set_log_level(LogLevel::Info);
+    proxy_wasm::set_root_context(|_| -> Box<dyn RootContext> { Box::new(HttpHeadersRoot) });
+}
+
+struct HttpHeadersRoot;
+
+impl Context for HttpHeadersRoot {}
+
+impl RootContext for HttpHeadersRoot {
+    fn get_type(&self) -> Option<ContextType> {
+        Some(ContextType::HttpContext)
+    }
+
+    fn create_http_context(&self, context_id: u32) -> Option<Box<dyn HttpContext>> {
+        Some(Box::new(HttpHeaders { context_id }))
+    }
+}
+
+struct HttpHeaders {
+    context_id: u32,
+}
+
+impl Context for HttpHeaders {}
+
+impl HttpContext for HttpHeaders {
+    fn on_http_request_headers(&mut self, _: usize) -> Action {
+        // Add metadata headers. These metadata headers will be added as dynamic metadata from the header to metadata filter.
+        self.add_http_request_header("x-3scale-service-key", "123456789");
+        self.add_http_request_header("x-3scale-application-key", "987654321");
+        info!("3scale metadata headers added from the request path");
+        Action::Continue
+    }
+
+    fn on_log(&mut self) {
+        info!("#{} completed.", self.context_id);
+    }
+}

header-to-metadata/docker-compose.yaml

@@ -0,0 +1,23 @@
+version: '3.7'
+services:
+  envoy:
+    build:
+      context: ./
+      dockerfile: ./resources/Dockerfile
+    depends_on:
+      - backend_service
+    networks: 
+      - envoymesh
+    ports:
+      - "9095:9095"
+      - "9000:9000"
+
+  backend_service:
+    build:
+      context: ../mock-backend
+      dockerfile: Dockerfile
+    networks:
+      - envoymesh
+
+networks:
+  envoymesh: {}