x

Node.js backend compatibility layer for moonbitlang/async in MoonBit, with native delegation and JS FFI implementations for process, fs, http, websocket, stdio, pipe, and sys.

moonbit

async

backend

compatibility

nodejs

process

filesystem

http

websocket

wasi

Download zip

Author

mizchi

Version

0.1.7

License

Apache-2.0

Repository

github.com/mizchi/x

Last updated

7 months ago

Downloads

203K

#mizchi/x

Node.js backend compatibility layer for moonbitlang/async in MoonBit.

mizchi/x keeps native behavior by delegating to moonbitlang/async, and provides JS FFI implementations so the same async-style code can run on --target js (Node.js) with minimal changes.

#Primary Goal

Run code written against moonbitlang/async on Node.js (--target js).
Keep native (--target native) semantics close by forwarding to upstream implementations.

mizchi/x: API is aligned with moonbitlang/async contracts (native-compatible surface).
mizchi/js/node: API is aligned with raw Node.js/JavaScript style APIs.

#Dependencies

Dependency	Version
moonbitlang/async	0.16.6
moonbitlang/x	0.4.40

#Packages

Package	Description
mizchi/x/process	Command execution (run, collect_output, collect_stdout, collect_stderr, collect_output_merged)
mizchi/x/fs	File system operations (read_file, write_file, exists, mkdir, readdir, remove, rmdir)
mizchi/x/http	HTTP client (get, post, put, get_stream, post_stream, put_stream)
mizchi/x/websocket	WebSocket client (connect, Conn::send_text, Conn::send_binary, Conn::recv, Conn::close)
mizchi/x/stdio	Standard I/O (stdin, stdout, stderr with @io.Reader/@io.Writer)
mizchi/x/pipe	In-memory pipes (pipe() → PipeRead/PipeWrite with @io.Reader/@io.Writer)
mizchi/x/sys	Environment variables and CLI args (get_env_var, get_cli_args, exit)

#Platform Support

Package	native	js	wasm	wasm-gc
process	Yes	Yes	stub	stub
fs	Yes	Yes	WASI P1	stub
http	Yes	Yes	stub	stub
websocket	Yes	Yes	stub	stub
stdio	Yes	Yes	stub	stub
pipe	Yes	Yes	stub	stub
sys	Yes	Yes	Yes	stub

Yes — Full implementation.
stub — Compiles but aborts at runtime with "not supported" message.
WASI P1 — Partial implementation using WASI Preview 1 syscalls.

#Upstream Compatibility

Compatibility with moonbitlang/async 0.16.6 / moonbitlang/x 0.4.40.

The wrapper re-exports upstream types and APIs with matching signatures. On native, each function delegates directly to the upstream implementation. On JS, equivalent behavior is provided via extern "js" FFI (Node.js).

#http (moonbitlang/async/http)

Upstream tests: 20 | Covered: 2 | Skipped: 18

Upstream test	Status	Notes
http request	Covered
https request	Covered
Other 18 tests	Skip	Internal parser/sender/proxy tests

#websocket (moonbitlang/async/websocket)

Upstream tests: 24 | Covered: 0 | Skipped: 24

All upstream tests are internal (frame handling, ping/pong, UTF-8 validation) and not applicable to the wrapper's high-level API. The wrapper has 24 independent tests covering its own API.

#pipe (moonbitlang/async/pipe)

Upstream tests: 3 | Covered: 3 | Skipped: 0

All upstream pipe tests are fully covered.

#stdio (moonbitlang/async/stdio)

Upstream tests: 3 | Covered: 0 | Skipped: 3

All upstream tests require process piping/redirect features (@process.run with redirect options).

#Quick Start

just           # check + test
just fmt       # format code
just check     # type check
just test      # run tests

#Upstream test coverage by package

Coverage is verified by scripts/sync-upstream-tests.sh, which extracts test names from the upstream packages and checks that each is either covered by a wrapper test or explicitly excluded in scripts/upstream-exclude.conf.

#process (moonbitlang/async/process)

Upstream tests: 28 | Covered: 10 | Skipped: 18

Upstream test	Status	Notes
basic wait	Covered
basic_ls	Covered
collect_stdout	Covered
collect_error	Covered
collect_output	Covered
collect_output_merged	Covered
wait exitcode	Covered
set cwd	Covered
set_env	Covered
set_env no inherit	Covered
basic_cat	Skip	stdin pipe not yet exposed
wait_pid	Skip	spawn_orphan not yet exposed
cancel process	Skip	cancellation not yet exposed
cancel process hard	Skip	cancellation not yet exposed
cancel process timeout	Skip	cancellation not yet exposed
orphan process	Skip	spawn_orphan not yet exposed
collect_output blocked	Skip	stdin param not yet exposed
spawn_in_group wait	Skip	spawn not yet exposed
spawn_in_group cancel	Skip	spawn not yet exposed
Process::wait	Skip	Process type not yet exposed
Process::try_wait	Skip	Process type not yet exposed
Process:cancel	Skip	Process type not yet exposed
merge stdout and stderr	Skip	stdout/stderr redirect not yet exposed
merge multiple	Skip	spawn + pipe redirect not yet exposed
redirect to file	Skip	file redirect not yet exposed
kill children on hard cancel	Skip	requires custom test program + Windows
do not kill orphan children on hard cancel	Skip	requires custom test program + Windows
windows command line arg escape	Skip	Windows-specific

#HTTP Server Operations (Node.js)

#Reverse proxy / TLS termination

When running @http.Server behind a reverse proxy (Nginx/Caddy/ALB), terminate TLS at the proxy and forward plain HTTP to the MoonBit process.

Enable proxy-aware client address resolution with:
- @http.Server::new(..., trust_proxy=true)
Current JS behavior:
- client_addr() uses x-forwarded-for (first hop) and x-forwarded-port
- falls back to x-forwarded-host port when x-forwarded-port is absent

Security note: set trust_proxy=true only when requests are guaranteed to come from trusted proxy hops.

#SSE shutdown benchmark

Run this JS-only benchmark test to check concurrent SSE shutdown behavior:

moon test --target js src/http --filter 'bench(js): graceful close time under concurrent sse'

The test prints a measurement line like:

bench(js): sse_clients=24 graceful_close_ms=1507

#k6 benchmark (default: JS vs Native)

Use the dedicated benchmark server package and k6 scenarios. By default, this runs both js and native targets and prints a comparison summary.

./scripts/k6/run_http_bench.sh

Environment variables:

PORT (default 18080)
VUS (default 128)
DURATION (default 20s)
BODY_SIZE (default 16384) for POST /consume
TARGETS (default "js native")
- e.g. TARGETS=js to run JS only
- e.g. TARGETS=native to run Native only

Individual scenarios:

BASE_URL=http://127.0.0.1:18080 k6 run scripts/k6/http_ping.js
BASE_URL=http://127.0.0.1:18080 BODY_SIZE=16384 k6 run scripts/k6/http_consume.js
BASE_URL=http://127.0.0.1:18080 BODY_SIZE=16384 k6 run scripts/k6/http_discard.js

#License

Apache-2.0

Install

Download zip

Node.js backend compatibility layer for moonbitlang/async in MoonBit, with native delegation and JS FFI implementations for process, fs, http, websocket, stdio, pipe, and sys.

moonbitasyncbackendcompatibilitynodejsprocessfilesystemhttpwebsocketwasi