WASM Rust

• Windows WSL used

• install rust & wasm : https://antweiss.com/blog/extending-envoy-with-wasm-and-rust/

• examples : https://github.com/proxy-wasm/proxy-wasm-rust-sdk/tree/master/examples

Set up wasm filter

cargo new --lib pekerustallround1

cd pekerustallround1

code . (Visual Studio Code)

change Cargo.toml

[lib]
crate-type = ["cdylib"]
path = "src/lib.rs"

[dependencies]
proxy-wasm = "0.1.3"
log = "0.4.8"
serde_json = "1.0"

change src/lib.rs to implement your code

LOCAL Testing (vs Istio envoy proxy)

• compile to wasm : cargo build --target wasm32-unknown-unknown --release

• docker-compose up

  • curl -v -H "info: my little secret" http://localhost:8080/anything

  • "secret" will be replaced with "open" in response, transponder configurations will be shown

  • json from config is parsed and value of "extraUrlsToMask" is shown in header info "Peke-Extra-Url-Mask" response

  • json config parsing is also used to get intermediate svc definition

  • call to intermediate service is done and value of result is upstreamed in header "Peke-First-Byte-Check"

• docker-compose down

ISTIO Testing

• install httpbin : kubectl apply -f httpbin.yaml

• install peke-echo : kubectl apply -f peke-echo.yaml

• build and tag image : wasme build precompiled ./target/wasm32-unknown-unknown/release/pekerustallround1.wasm -t webassemblyhub.io/peke/pekerustallround:v0.1

• verify image : wasme list

• push image :

  • wasme login -u Peke
  • wasme push webassemblyhub.io/peke/pekerustallround:v0.1

• install wasme operator/cache 0.0.32 (if startup hangs, remove all FilterDeployments and reinstall wasme operator)

• install filterDeployment for peke-echo : kubectl apply -f peke-echo-v1-pekerustallround.yaml

• if filter doens't get pulled (see logs of wasme operator) : delete (and restart) wasme operator pod