lib/cherrypy/tutorial/tut05_derived_objects.py

   1 """
   2 Tutorial - Object inheritance
   3
   4 You are free to derive your request handler classes from any base
   5 class you wish. In most real-world applications, you will probably
   6 want to create a central base class used for all your pages, which takes
   7 care of things like printing a common page header and footer.
   8 """
   9
  10 import cherrypy
  11
  12
  13 class Page:
  14     # Store the page title in a class attribute
  15     title = 'Untitled Page'
  16
  17     def header(self):
  18         return '''
  19             <html>
  20             <head>
  21                 <title>%s</title>
  22             <head>
  23             <body>
  24             <h2>%s</h2>
  25         ''' % (self.title, self.title)
  26
  27     def footer(self):
  28         return '''
  29             </body>
  30             </html>
  31         '''
  32
  33     # Note that header and footer don't get their exposed attributes
  34     # set to True. This isn't necessary since the user isn't supposed
  35     # to call header or footer directly; instead, we'll call them from
  36     # within the actually exposed handler methods defined in this
  37     # class' subclasses.
  38
  39
  40 class HomePage(Page):
  41     # Different title for this page
  42     title = 'Tutorial 5'
  43
  44     def __init__(self):
  45         # create a subpage
  46         self.another = AnotherPage()
  47
  48     def index(self):
  49         # Note that we call the header and footer methods inherited
  50         # from the Page class!
  51         return self.header() + '''
  52             <p>
  53             Isn't this exciting? There's
  54             <a href="./another/">another page</a>, too!
  55             </p>
  56         ''' + self.footer()
  57     index.exposed = True
  58
  59
  60 class AnotherPage(Page):
  61     title = 'Another Page'
  62
  63     def index(self):
  64         return self.header() + '''
  65             <p>
  66             And this is the amazing second page!
  67             </p>
  68         ''' + self.footer()
  69     index.exposed = True
  70
  71
  72 import os.path
  73 tutconf = os.path.join(os.path.dirname(__file__), 'tutorial.conf')
  74
  75 if __name__ == '__main__':
  76     # CherryPy always starts with app.root when trying to map request URIs
  77     # to objects, so we need to mount a request handler root. A request
  78     # to '/' will be mapped to HelloWorld().index().
  79     cherrypy.quickstart(HomePage(), config=tutconf)
  80 else:
  81     # This branch is for the test suite; you can ignore it.
  82     cherrypy.tree.mount(HomePage(), config=tutconf)
  83