Boxed HTTP Server

WebAssembly sandbox static HTTP server with HTTP Basic auth and proxy support. Use when starting a static file server, configuring HTTP authentication, setting up HTTP proxy/reverse proxy, or running a local development server.

A lightweight static HTTP server based on WebAssembly sandbox, with support for HTTP Basic authentication and HTTP proxy/reverse proxy.

Trigger When

Use this skill when the user describes (触发场景):

• Starting a static file server (启动静态文件服务器)
• Configuring HTTP Basic authentication (配置 HTTP 认证)
• Setting up HTTP proxy or reverse proxy (设置 HTTP 代理或反向代理)
• Running a local development server (搭建本地开发服务器)
• Deploying a static website (部署静态网站)
• Adding authentication to a static site (为静态网站添加认证保护)

Prerequisites

• openclaw-wasm-sandbox plugin: Must be installed and enabled, version >=0.4.0
• wasm file download: Download required before first use

Download wasm File

js

wasm-sandbox-download({
  url: "https://raw.githubusercontent.com/guyoung/wasm-sandbox-openclaw-skills/main/boxed-http-server/files/boxed_http_server_component.wasm",
  dest: "~/.openclaw/skills/boxed-http-server/files/boxed_http_server_component.wasm"
})

Or via command line:

bash

curl -L -o ~/.openclaw/skills/boxed-http-server/files/boxed_http_server_component.wasm \
  "https://raw.githubusercontent.com/guyoung/wasm-sandbox-openclaw-skills/main/boxed-http-server/files/boxed_http_server_component.wasm"

Start Static File Server

js

wasm-sandbox-serve({
  wasmFile: "~/.openclaw/skills/boxed-http-server/files/boxed_http_server_component.wasm",
  workDir: ["~/.openclaw/skills/boxed-http-server/files"]
})

Or via command line:

bash

openclaw wasm-sandbox serve ~/.openclaw/skills/boxed-http-server/files/boxed_http_server_component.wasm \
  -i 192.168.1.100 -p 8080 --work-dir /path/to/website

HTTP Basic Authentication

Protect your website with username/password authentication:

js

wasm-sandbox-serve({
  wasmFile: "~/.openclaw/skills/boxed-http-server/files/boxed_http_server_component.wasm",
  workDir: ["~/.openclaw/skills/boxed-http-server/files"],
  args: ["--config-var", "username=admin", "--config-var", "password=admin"]
})

HTTP Proxy / Reverse Proxy

Proxy external APIs through the server. Requires allowedOutboundHosts for the target domain:

js

wasm-sandbox-serve({
  wasmFile: "~/.openclaw/skills/boxed-http-server/files/boxed_http_server_component.wasm",
  workDir: ["~/.openclaw/skills/boxed-http-server/files"],
  allowedOutboundHosts: ["https://httpbin.org"],
  args: ["--config-var", "proxy=\"[{\\\"path\\\": \\\"/httpbin\\\",\\\"target\\\" :\\\"https://httpbin.org\\\",\\\"headers\\\": {\\\"Authorization\\\": \\\"Bearer abcd1234\\\"}}]\""]
})

Combined Example: Static Site + API Proxy

Serve a static website while proxying external APIs to avoid CORS issues:

js

wasm-sandbox-serve({
  wasmFile: "~/.openclaw/skills/boxed-http-server/files/boxed_http_server_component.wasm",
  workDir: ["/home/user/website"],
  allowedOutboundHosts: ["https://api.weather.com", "https://wttr.in"],
  args: ["--config-var", "proxy=\"[{\\\"path\\\": \\\"/weather\\\",\\\"target\\\": \\\"https://wttr.in\\\"}]\""]
})

Then update your frontend to call /weather instead of the external API directly.

Parameters

Parameter	Type	Required	Description
wasmFile	string	Yes	Path to the wasm component file
workDir	string[]	Yes	Website root directories (served as static files)
allowedOutboundHosts	string[]	No	Allowed external domains for proxy mode
args	string[]	No	Command-line args for auth and proxy config

CLI Options (for openclaw wasm-sandbox serve)

Option	Short	Description
--ip <ip>	-i	Socket IP to bind to
--port <port>	-p	Socket port to bind to (0-65535)
--work-dir <dir>		Website root directory
--config-var <var>		WASI config variables
--allowed-outbound-hosts <hosts>		Allowed external domains (proxy mode)

Available args Config

• --config-var username=<username> - Set Basic auth username
• --config-var password=<password> - Set Basic auth password
• --config-var proxy=<JSON> - Set proxy rules in JSON format

proxy Config Format

json

[
  {
    "path": "/httpbin",
    "target": "https://httpbin.org",
    "headers": {
      "Authorization": "Bearer abcd1234"
    }
  }
]

Field	Type	Description
path	string	Proxy path prefix (requests matching this prefix will be proxied)
target	string	Target full URL
headers	object	Optional custom headers to add to the proxied request

Security Model

Boxed HTTP Server runs inside WebAssembly sandbox with capability-based security:

• No implicit access: WASM module has zero access by default
• Explicit grants only: Access must be explicitly allowed via configuration
• Network isolation: Outbound network access is denied by default
• Resource limits: Supports timeout, memory, stack size, and fuel limits

Architecture

text

User Request
    ↓
OpenClaw Gateway
    ↓
Wasm Sandbox Plugin
    ↓
boxed_http_server_component.wasm
    ↓
├── Static File Handler (workDir)
├── Basic Auth Handler (args: username/password)
└── Proxy Handler (args: proxy config)
    ↓
Response to Client

Example: Full Deployment

Deploy a static website at http://192.168.158.134:8080:

bash

# 1. Download wasm file (if not exists)
curl -L -o ~/.openclaw/skills/boxed-http-server/files/boxed_http_server_component.wasm \
  "https://raw.githubusercontent.com/guyoung/wasm-sandbox-openclaw-skills/main/boxed-http-server/files/boxed_http_server_component.wasm"

# 2. Start server
openclaw wasm-sandbox serve \
  ~/.openclaw/skills/boxed-http-server/files/boxed_http_server_component.wasm \
  -i 192.168.158.134 \
  -p 8080 \
  --work-dir /home/user/website

Troubleshooting

Issue	Solution
"wasm file not found"	Run the download step first
"Connection refused"	Check IP and port, ensure firewall allows access
"CORS errors in frontend"	Use proxy mode to route external APIs through the server
"Authentication not working"	Ensure username and password are set in args
"Proxy returns 403"	Add target domain to allowedOutboundHosts