Wsgi-15Watt

A slim, fast and comfortable WSGI-Framework for Python >= 3.6.
Tested with 3.10 + 3.12.
Uses https://github.com/defnull/multipart for handling the multipart/form-data requests instead of cgi.FieldStorage.

Installation

PIP

pip3 install Wsgi_15Watt

Git

You can clone the repository and install the package to a directory, from where you can import python packages.

    cd /path/to/your/import/able/python/packages
    git clone git@github.com:django15wattnet/15Watt_Wsgi.git

SRC Documentation

See

Usage

The Apache2 Configuration

Read the mod_wsgi docu.

<VirtualHost x.x.x.x:port>
    ServerName your.server.name
    DocumentRoot /path/to/static/files                          # Where your static html-files are stored
    
    WSGIScriptAlias / /path/to/python/files/application.py      # Where your application.py is stored and invoked by calling http[s]://your.server.name/
    WSGIProcessGroup name_of_your_wsgi_daemon_process           # The name of your WSGIDaemonProcess
    
    # For development, each request loads a new python interpreter / application.py, no need the reload the web server
    WSGIDaemonProcess name_of_your_wsgi_daemon_process user=yourUnixUser group=yourUnixGroup processes=1 threads=1 maximum-requests=1 home=/path/to/python/files python-path=/path/to/python/files
    
    # For a production enviroment change processes, threads and maximum-requests to your needes
    
    # The confiuration for the static files
    <Directory /path/to/static/files/>
    # Read the Apache2 docu https://httpd.apache.org/docs/2.4/mod/core.html#directory
       Options -Indexes -FollowSymLinks -MultiViews -Includes
       AllowOverride None
       Require all granted
       allow from all
    </Directory>
    
    # The configuration for the application directory
    <Directory /path/to/python/files/>
    # Read the Apache2 docu https://httpd.apache.org/docs/2.4/mod/core.html#directory
        Require all granted
        Options FollowSymLinks
        AllowOverride None
        Header set Access-Control-Allow-Origin '*'          # I'm not sure if this is needed
    </Directory>
    
    # Alias for the static, directly by the web server, deliveryed files and directories
    Alias /favicon.ico /path/to/static/files/favicon.ico
    Alias /css/ /path/to/static/files/css/
    Alias /js/ /path/to/static/files/js/
    Alias /img/ /path/to/static/files/img/ 
    
    ...
    
    # Your other Apache configurations
    
    </VirtualHost>

Project Layout

@ToDo

The Application

Create a application.py file in /path/to/python/files:

#!/usr/bin/env python
from Wsgi-15Watt.Kernel import Kernel

kernel = None

def application(env: dict, start_response):
	global kernel

	if kernel is None:
		kernel = Kernel()

	return kernel.run(env=env, startResponse=start_response)

All requests are handled by the Kernel.run method. WSGIScriptAlias / /path/to/python/files/application.py
The Kernel is a singleton and is created only once per lifetime of the application. By this, the configuration und the routes are loaded only once.
Only files and/or directories definded by Apache Alias directives are delivered by the web server drircetly!

Routes

The routes definitions tells the Kernel witch request path ist mapped to witch controller and method.
Create a routes.py file in /path/to/python/files:

Example routes without parameters in the path

from Wsgi-15Watt.Route import Route, HttpMethods

routes = [
	Route(
		path='/',
		nameController='Controllers.AggregationController.AggregationController',
		nameMethod='staticPageAction',
		httpMethod=HttpMethods.GET
	),
	Route(
		path='/qcell',
		nameController='QCell.StaticPagesController.StaticPagesController',
		nameMethod='indexAction',
		httpMethod=HttpMethods.GET
	),
]

A request to / will be handled by from Controllers.AggregationController import AggregationController staticPageAction method.
A request to /qcell will be handled by from QCell.StaticPagesController import StaticPagesController indexAction method.

Example routes with parameters in the path

from Wsgi-15Watt.Route import Route, HttpMethods

routes = [
	Route(
		path='/do/{id}/{what}',
		nameController='Controllers.DoWiredStuffController.DoWiredStuffController',
		nameMethod='doStuffAction',
		httpMethod=HttpMethods.GET,
		params = {
                    'id': 'int',
                    'what': 'str'
                }
	),
    ...
]

A request to /do/42/machWas will be handled by from Controllers.DoWiredStuffController import DoWiredStuffController
doStuffAction method with the parameters id=42 and what='machWas'.
The types of the parameters in the path can be python types ìnt or str.

Route names

Routes have names.
They are build automatically, or set throw the parameter name in the Route constructor. The automatically build name of a route is build by the name of the controller and the name of the method.

def nameMatches(self, lstNames: list|str = []) -> bool:
The method nameMatches of the Route class checks if the name of the route matches one of the names in the list lstNames.

The Request Class

represents the request from the client.
Have a look at the, hopefully, well documented code.

The Response Class

represents the response send to the client.
Have a look at the, hopefully, well documented code.

Controllers

The controllers orchestrate the work to be done. Receive the request, do the work and return the response.

A very simple example Controller

from Wsgi-15Watt.BaseController import BaseController
from Wsgi-15Watt.Request import Request
from Wsgi-15Watt.Response import Response


class ExampleController(BaseController):

	def __init__(self, config: dict):
		super().__init__(config=config)


	def getAction(self, request: Request, response: Response):
		response.stringContent = 'Hello World'
		response.contentType = 'text/plain
		response.returnCode = 200
		return

Will send the string 'Hello World' with the content type 'text/plain' and the return code 200 to the client.
Do what ever you want in your getAction method 😊.

A controller with a method that gets parameters from the route

The route with parameters in the path /path/to/python/files/routes.py:

from Wsgi-15Watt.Route import Route, HttpMethods

routes = [
	Route(
		path='/with/params/{id}/{what}',
		nameController='Controllers.ExampleController.ExampleController',
		nameMethod='withParamsAction',
		httpMethod=HttpMethods.GET,
		params = {
                    'id': 'int',
                    'what': 'str'
                }
	)
]

The controller /path/to/python/files/Controllers/ExampleController.py:

from Wsgi-15Watt.BaseController import BaseController
from Wsgi-15Watt.Request import Request
from Wsgi-15Watt.Response import Response


class ExampleController(BaseController):

	def __init__(self, config: dict):
		super().__init__(config=config)


	def withParamsAction(self, request: Request, response: Response):
		response.stringContent = f'Hello World, id = {request.get('id)} what = "{request.get('what')"}'
		response.contentType = 'text/plain
		response.returnCode = 200
		return

When the client requests /with/params/42/machWas
the response will be Hello World, id = 42 what = "machWas"
with the content type 'text/plain' and the return code 200.

request.get('id) will return the value of the parameter id as type int from the request.
request.get('what) will return the value of the parameter what as type str from the request.

The configuration file

is expected in /path/to/python/files/config.py
as a simple assignments of variables to values.

key1 = 'Value1'
confVar2 = 42

The Kernel will load the configuration file and make the variables, as a dict, available to the controllers,
in the property 'self._config
whit this content:

{
    'key1': 'Value1', 
    'confVar2': 42
}

Templates

I use Cheetah3 for the templates.
Use what ever you like as your template engine.
At this moment (2024-06-01) I'm not shure the BaseTplController is necessary.
If you like to use Cheetah3, have a look at the WsgiCheetah3_15Watt extension.

How to create the documentation

The documentation is generated by pdoc. cd into the directory above the Wsgi_15Watt directory and run:

PYTHONPATH=. python3 -m pdoc -o Wsgi_15Watt/docs Wsgi_15Watt

Extensions

• WsgiCheetah3_15Watt: An extension to use Cheetah3 templates comfortable.
• WsgiSqlObject_15Watt: Adds SQLObject support to Wsgi_15Watt.

ToDos

• Find a way to determine that a uri (with parameters) matches a route
  • vulgo: find a way to determine that the request path /do/42/machWas matches the route /do/{id}/{what}
• Change the language of the comments and documentation from german to english
• Write and test a configuration for nginx