Py4js

a fast and simple micro-framework for small web applications

Generate Convert Improve

Install / Use

/learn @lixk/Py4js

About this skill

Quality Score

0/100

README

py4js

py4js is a fast and simple micro-framework for small web applications. Its goal is to enable you to develop web applications in a simple and understandable way.

With it, you don't need to know the HTTP protocol, or how Python communicates with JavaScript. You can use Python functions in JavaScript just like native JavaScript functions.

Usage steps

Step 1

Install py4js package: pip install py4js or pip3 install py4js

Step 2

First, create a package, named service, and then create a Python file in the package, such as hello.py:

def say_hello(name):
    """
    say hello test

    :param name:
    :return:
    """
    return 'Hello %s!' % name

Step 3

Create a Python file that is at the same level as the service package, such as main.py:

from py4js import Server

Server().run()

Then run it(By default, the server will launch wsgiref server at port 5000. You can also use other port and wsgi server).

Step 4

Create a HTML file, anywhere, such as index.html:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>hello</title>
    <script src="http://localhost:5000/service.js"></script>
</head>
<body>
    <script>
        service.hello.say_hello('World', function(data){
            alert(data);
        });
    </script>
</body>
</html>

Open the index.htmlin browser and you will see the alert message:

It's so easy, yes?

Server

Server parameters

The server has several startup parameters that can be specified, for example:

| Name | Description | | :--- | :--- | | host | Server address to bind to(default: 0.0.0.0). Pass 0.0.0.0 to listens on all services including the external one. | | port | Server port to bind to(default: 5000). Values below 1024 require root privileges. if port is None, server will use a random port. | | server | Specify the server adapter to use. For more details: Server adapter. (default: wsgiref, others: paste/waitress/gevent/cherrypy/gunicorn.etc). | | service_package | A package that will be scanned by the server. All modules and public functions in the package will be loaded as service for JavaScript. Default package name is service, also you can change it to another name if you like. | | js_route | the path of JavaScript for browser to load. | | access_control_allow_origin | default: * , all cross domain requests are allowed. |

Server adapter

As the py4js server is based on Bottle, the built-in default server is based on wsgiref WSGIServer. This non-threading HTTP server may become a performance bottleneck when server load increases. So it's better to use a different server that is either multi-threaded or supports asynchronous IO.

Bottle ships with a lot of ready-to-use adapters for the most common WSGI servers, such as: cherrypy, paste, waitress, gevent, eventlet, tornado, twisted.etc. Usage:

waitress
```
from py4js import Server

Server(server='waitress').run()
```
If you haven't installed the waitress package, please install it first by pip install waitress or pip3 install waitress.
gevent
```
from gevent import monkey

from py4js import Server

monkey.patch_all()

Server(server='gevent').run()
```
If you haven't installed the gevent package, please install it first by pip install gevent or pip3 install gevent.
As gevent is Asynchronous, the server can be very fast, can handle a virtually unlimited number of concurrent connections and are easy to manage.

Related Skills

node-connect

343.1k

Diagnose OpenClaw node connection and pairing failures for Android, iOS, and macOS companion apps

frontend-design

90.0k

Create distinctive, production-grade frontend interfaces with high design quality. Use this skill when the user asks to build web components, pages, or applications. Generates creative, polished code that avoids generic AI aesthetics.

openai-whisper-api

343.1k

Transcribe audio via OpenAI Audio Transcriptions API (Whisper).

qqbot-media

343.1k

QQBot 富媒体收发能力。使用 <qqmedia> 标签，系统根据文件扩展名自动识别类型（图片/语音/视频/文件）。