CherryPy

CherryPy

Developer(s)	CherryPy team
Stable release	5.1.0[1] / March 10, 2016
Written in	Python
Operating system	Cross-platform
Type	Web application framework
License	BSD License[2]
Website	www.cherrypy.org

CherryPy is an object-oriented web application framework using the Python programming language. It is designed for rapid development of web applications by wrapping the HTTP protocol but stays at a low level and does not offer much more than what is defined in RFC 7231.

CherryPy can be a web server itself or one can launch it via any WSGI compatible environment. It does not deal with tasks such as templating for output rendering or backend access. The framework is extensible with filters, which are called at defined points in the request/response processing.

Pythonic interface

One of the goals of the project founder, Remi Delon, was to make CherryPy as pythonic as possible. This allows the developer to use the framework as any regular Python module and to forget (from a technical point of view) that the application is for the web.

For instance, the common Hello World program with CherryPy 3 would look like:

import cherrypy

class HelloWorld(object):
    def index(self):
        return "Hello World!"
    index.exposed = True

cherrypy.quickstart(HelloWorld())

Features

CherryPy implements:

• A HTTP/1.1-compliant, WSGI thread-pooled webserver.^[3] Typically, CherryPy itself takes only 1-2 ms per page.^[4][5]
• Support for any other WSGI-enabled web server or adapter, including Apache, IIS, lighttpd, mod_python, FastCGI, SCGI, and mod_wsgi.
• A native mod_python adapter.
• Multiple HTTP servers (e.g. ability to listen on multiple ports).^[6]
• A plugin system^[7] CherryPy plugins hook into events within the server process — into server startup, server shutdown, server exiting, etc. — to run code that needs to be run when the server starts up or shuts down.
• Built-in tools for caching, encoding, sessions, authorization, static content, and others. CherryPy tools hook into events within the request process. Whenever the CherryPy server receives a request, there is a specific set of steps it goes through to handle that request. Page handlers are only one step in the process. Tools also provide a syntax and configuration API for turning them on and off for a specific set of handlers.
• A configuration system for developers and deployers .^[8][9][10] CherryPy deployments are configurable on site, on application and on controller level, through Python dictionaries, configuration files, and open file objects.
• A complete test suite for core functionality and associated framework which can be used to test CherryPy applications.^[11]
• Built-in profiling since v2.1,^[12] coverage^[13] and testing support.

CherryPy doesn’t force you to use a specific object-relational mapper (ORM), template language or JavaScript library.

Can be used with CherryPy

• Routes^[14] — a Python re-implementation of the Ruby on Rails's routes system for mapping URLs to controllers/actions and generating URLs.

Object-relational mappers

• SQLAlchemy — a database backend and ORM for Python applications. TurboGears 2.x uses CherryPy as server and SQLAlchemy as its default ORM.^[15]
• SQLObject — a popular ORM for providing an object interface to a database. Supports a number of common database backends: included in the distribution are MySQL, PostgreSQL, SQLite, Sybase SQL Server, MaxDB, Microsoft SQL Server and Firebird. TurboGears 1.x uses CherryPy as server and SQLObject as ORM.^[16]
• Storm — the ORM from Canonical Ltd. (makers of Ubuntu)
• Peewee — a simple and small ORM. It has few (but expressive) concepts, making it easy to learn and intuitive to use
• Dejavu^[17] — a public domain software, thread-safe ORM for Python applications
• MongoEngine — An ODM for connecting to MongoDB.

Templating languages

• Mako^[18] — a template library written in Python, usable with a simple CherryPy tool.^[19]
• Cheetah — an open source template engine and code generation tool, written in Python.
• CherryTemplate — a templating language for CherryPy.
• Genshi^[20][21] — a powerful XML templating language.
• Jinja — a general purpose templating language. CherryPy has a tool for using Jinja templates.^[22]
• Kid — a simple template language for XML based vocabularies written in Python. TurboGears 1.x uses CherryPy as server and Kid as frontend.^[23]

CherryPy wiki helps^[24] choosing a templating language.

JavaScript libraries

• Sarissa^[25] — a cross-browser library for Ajax
• jQuery — a lightweight library that emphasizes interaction between JavaScript and HTML
• Pyjamas — a Python to JavaScript compiler and a web widget set

Products using CherryPy

• TurboGears — CherryPy 2.x is a main component of TurboGears 1.x.
• Splunk Enterprise - CherryPy 3.1.2^[26]

References

1. https://pypi.python.org/pypi/CherryPy/5.1.0
2. "cherrypy / CherryPy / source / cherrypy / LICENSE.txt". BitBucket. Retrieved 21 February 2015.
3. http://www.cherrypy.org/#Features
4. CherryPy v3 WSGI server benchmark results
5. How fast is CherryPy?
6. How to set up multiple HTTP servers with CherryPy
7. Custom engine plugins with CherryPy
8. Configuration system of CherryPy
9. Configuration API of CherryPy
10. Short summary of configuration options
11. How to test CherryPy itself
12. Profiler module of CherryPy
13. How to collect and the analyse coverage data of application code with CherryPy
14. A simple dispatcher tool for CherryPy that uses Routes
15. TurboGears 2.x uses CherryPy as server and SQLAlchemy as its default ORM
16. TurboGears 1.x uses CherryPy as server and SQLObject as ORM
17. Dejavu
18. Mako
19. A simple CherryPy tool for Mako templating
20. "CherryPy – Genshi". Retrieved 2009-09-26.
21. "Genshi - CherryPy Tools - Trac". Retrieved 2009-09-26.
22. A basic CherryPy Tool for using Jinja templates
23. TurboGears 1.x uses CherryPy as server and Kid as frontend
24. CherryPy wiki about choosing a templating language
25. http://sourceforge.net/projects/sarissa/files/
26. http://docs.splunk.com/Documentation/Splunk/latest/ReleaseNotes/CherryPy

External links

• Official website
• mailing list
• Documentation
• Feeds about CherryPy
• CherryPy on Freshmeat
• CherryPy on Ohloh
• Websites running atop CherryPy
• People who use CherryPy
• Products based on or inspired by CherryPy