from concurrence import dispatch
from concurrence.web import Application, Controller, Filter, web
class PageFilter(Filter):
"""A filter that surrounds the upstream response with a complete html page"""
def __call__(self, next, *args, **kwargs):
#A Filter is a callable object and is part of a chain of filters configured for
#a certain Action. A filter uses the `next` argument to call the next filter in the chain.
return """
<html>
<head>
<title>Example Page</title>
</head>
<body style='background-color: #a0f0f0'>
%s
</body>
</html>""" % next(*args, **kwargs)
class WrapperFilter(Filter):
"""A filter that surrounds the upstream response with a tag"""
def __init__(self, tag):
self.tag = tag
def __call__(self, next, *args, **kwargs):
return "<%s>%s</%s>" % (self.tag, next(*args, **kwargs), self.tag)
class ExampleController(Controller):
"""A Controller contains multiple Actions. A controller
method becomes an Action by adding a `web.route` decorator that links the method to an url."""
#controller level filters are applied to all actions in the controller
__filters__ = [PageFilter()]
#a action may be linked to multiple urls
@web.route('/greeting')
@web.route('/welcome')
def hello(self):
return "Hello World"
@web.route('/farewell')
def goodbye(self):
return "Goodbye"
@web.route('/sum')
def sum(self):
msg = self.request.params.getone('msg')
a = int(self.request.params.getone('a'))
b = int(self.request.params.getone('b'))
return '%s %d' % (msg, a + b)
#in addition to the controller level filters, an action may also supply its own filters
@web.route('/wrapper')
@web.filter(WrapperFilter('h1'))
@web.filter(WrapperFilter('strong'))
def wrapper(self):
return "Testing 132"
def main():
#create a web application
application = Application()
application.add_controller(ExampleController())
application.configure()
application.serve(('localhost', 8080))
if __name__ == '__main__':
dispatch(main)
