Kong / proxy-wasm-rust-rate-limiting

Rust implementation of a prototype rate-limiting filter using proxy-wasm

proxy-wasm-rust-rate-limiting

A prototype implementation of a rate-limiting filter written in Rust, using the proxy-wasm API for running on WebAssembly-enabled gateways.

What's implemented

• "local" policy only, using the SHM-based key-value store

What's missing

• Getting proper route and service ids for producing identifiers.
• Other policies, which would require additional features from the underlying system, such as calling out to a Redis instance.

Build requirements

• Rust
  • rustup.rs is the easiest way to install Rust.
    • Then add the Wasm32-WASI target to your toolchain: rustup target add wasm32-wasi.

Building and running

Once the environment is set up with cargo in your PATH, you can build it with:

cargo build --release

This will produce a .wasm file in target/wasm32-wasi/release/.

Once you have a Wasm-enabled Kong container with a recent ngx_wasm_module integrated (the container from the Summit 2022 Tech Preview is too old), you can run the script in test/demo.sh to give the filter a spin.

You also need the kong_wasm_rate_limiting_counters shared memory key-value store enabled in your Kong configuration. One way to achieve this is via the following environment variable:

export KONG_NGINX_WASM_SHM_KV_KONG_WASM_RATE_LIMITING_COUNTERS=12m