WebAssembly for Proxies (AssemblyScript SDK)
This is a friendly fork of https://github.com/solo-io/proxy-runtime/, temporarily mantained to address one incompatibility between the SDK and ngx_wasm_module.
This fork should no longer be needed once that is handled in the upstream.
How to use this SDK
Create a new project:
npm init
npm install --save-dev assemblyscript
npx asinit .
Include "use": "abort=abort_proc_exit"
to the asconfig.json
file as part of
the options passed to asc
compiler:
{
"options": {
"use": "abort=abort_proc_exit"
}
}
Add "@kong/proxy-wasm-sdk": "0.0.6"
to your dependencies then run npm install
.
Hello, World
Copy this into assembly/index.ts:
export * from "@kong/proxy-wasm-sdk/proxy";
import {
RootContext,
Context,
registerRootContext,
FilterHeadersStatusValues,
stream_context
} from "@kong/proxy-wasm-sdk";
class AddHeaderRoot extends RootContext {
createContext(context_id: u32): Context {
return new AddHeader(context_id, this);
}
}
class AddHeader extends Context {
constructor(context_id: u32, root_context: AddHeaderRoot) {
super(context_id, root_context);
}
onResponseHeaders(a: u32, end_of_stream: bool): FilterHeadersStatusValues {
const root_context = this.root_context;
if (root_context.getConfiguration() == "") {
stream_context.headers.response.add("hello", "world!");
} else {
stream_context.headers.response.add("hello", root_context.getConfiguration());
}
return FilterHeadersStatusValues.Continue;
}
}
registerRootContext((context_id: u32) => { return new AddHeaderRoot(context_id); }, "add_header");
build
To build, simply run:
npm run asbuild
build results will be in the build folder. untouched.wasm
and optimized.wasm
are the compiled
file that we will use (you only need one of them, if unsure use optimized.wasm
).
Run
Configure envoy with your filter:
- name: envoy.filters.http.wasm
config:
config:
name: "add_header"
root_id: "add_header"
configuration: "what ever you want"
vm_config:
vm_id: "my_vm_id"
runtime: "envoy.wasm.runtime.v8"
code:
local:
filename: /PATH/TO/CODE/build/optimized.wasm
allow_precompiled: false