Proxy-Wasm Go Filter Template

This repository contains a Proxy-Wasm filter that can be used as a reference to quickly start implementing new filters in Go.

This is a "hello-world" type filter performing a minimal operation and showing the basics of filter configuration: it simply adds a new header X-Greeting to a proxied response. You can pass the filter a JSON configuration in the format { "my_greeting": "Howdy!" } to change the value of the injected header.

Please refer to WasmX docs for the list of supported functions and entrypoints.

Requirements

• tinygo - a Go compiler that can produce WebAssembly code.
• proxy-wasm-go-sdk - the SDK whihc implements the proxy-wasm API
• ffjson - a code-generation based JSON library for Go; this is used to demonstrate the parsing of JSON configuration in filters. Once you install this, you need the ffjson utility in your PATH for building.

Build

Once the environment is set up with the requirements, build the filter running make.

This will produce a .wasm file in the root of the project.