example

package

v0.18.3 Latest Latest Go to latest Published: Mar 17, 2026 License: MIT Imports: 8 Imported by: 0

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Valid go.mod file
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Repository

github.com/pancsta/asyncmachine-go

Links

Open Source Insights

README ¶

/examples/WASM

cd /

[!NOTE] asyncmachine-go is a batteries-included graph control flow library (AOP, actor model, state-machine).

This is a simple example of WASM interop and communication between two distributed async state machines (foo and bar). The complete WASM support allows having a single state-machine which is fully (or selectively) distributed across n servers and m browsers, using efficient diff-based synchronization.

Actors (server):

server-foo main state machine
- RPC server (WS)
aRPC client (WS / TCP)
- rc-server-bar network mach

Actors (browser):

browser-bar UI state machine
- RPC server (WS / TCP over WS)
aRPC client (WS)
- rnm-browser-foo network mach
- browser-foo net handler mach

Running

git clone https://github.com/pancsta/asyncmachine-go.git
cd asyncmachine-go/examples/wasm
task start

no task? https://taskfile.dev/docs/installation

Implementation

net/rpc, cenkalti/rpc2, and coder/websocket with TCP-over-WebSocket bridged using /tools/cmd/am-relay.

logical diagram

Debugging

Both server-foo and browser-bar connect to a single am-dbg instance running on the server and can be stepped through, with context from all the other machines.

Both server-foo and browser-bar expose REPLs.

am-dbg WASM

Interactively use the TUI debugger with data pre-generated by this example:

go run github.com/pancsta/asyncmachine-go/tools/cmd/am-dbg@latest \
  --import-data https://assets.asyncmachine.dev/am-dbg-exports/wasm.gob.br \
  mach://server-foo

Machine Diagrams

# render
am-vis --bird render-dump am-dbg-dump.gob.br

am-dbg WASM

Extended Network Diagram

The extended machine diagram additionally contains RPC clients and servers (aka noise).

# generate with .env
AM_RPC_LOG_SERVER=1
AM_RPC_LOG_CLIENT=1
AM_RPC_LOG_MUX=1
AM_RPC_DBG=1

# render
am-vis --bird render-dump am-dbg-dump.gob.br

Click to expand the diagram

am-dbg WASM

Commands

$ task --list-all

task: Available tasks for this project:
* build:            Development build
* build-prod:       Optimized build
* deps:             List dependencies in deps.md
* deps-graph:       Render dependencies graph in deps-graph.svg
* repl:             Start REPL for both server and browser
* start:            Build and start server

Further Work

The current implementation covers the server-browser network boundary being synchronized using aRPC, but WebWorkers require additional bindings. This includes exposing ports, channels, and ArrayBuffer as a regular net/Conn. Because WebWorkers have access to WebSockets and fetch(), the main thread can be left to executing UI changes only, while n workers (n == CPU cores - 1) will:

process handlers for the same async state machine
run a KV cache store
run a DB via File System API

monorepo

Go back to the monorepo root to continue reading.

Documentation ¶

Index ¶

Constants
Variables
func LogArgs(args am.A) map[string]string
func ParseRpc(args am.A) am.A
func Pass(args *A) am.A
func PassRpc(args *ARpc) am.A
type A
- func ParseArgs(args am.A) *A
type ARpc

Constants ¶

View Source

const APrefix = "wasm"

Variables ¶

View Source

var (
	EnvFooTcpAddr  string
	EnvFooReplAddr string
)

View Source

var (
	EnvBarTcpAddr  string
	EnvBarReplAddr string
)

View Source

var (
	EnvRelayHttpAddr string
	EnvReplDir       string
)

Functions ¶

func LogArgs ¶

func LogArgs(args am.A) map[string]string

LogArgs is an args logger for A.

func ParseRpc ¶

func ParseRpc(args am.A) am.A

ParseRpc parses am.A to *ARpc wrapped in am.A. Useful for REPLs.

func Pass ¶

func Pass(args *A) am.A

Pass prepares am.A from A to pass to further mutations.

func PassRpc ¶

func PassRpc(args *ARpc) am.A

PassRpc prepares am.A from A to pass over RPC.

Types ¶

type A ¶

type A struct {
	Msg string `log:"msg"`

	ReturnCh chan<- []string
}

A is a struct for node arguments. It's a typesafe alternative to am.A.

func ParseArgs ¶

func ParseArgs(args am.A) *A

ParseArgs extracts A from am.Event.Args APrefix.

type ARpc ¶

type ARpc struct {
	Msg string `log:"msg"`
}

ARpc is a subset of A, that can be passed over RPC.

Source Files ¶

View all Source files

wasm_example.go

Directories ¶

Path	Synopsis
client
server
states

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