I hope the following helps explain the separation for an MVC design I
described earlier. It's really just off the top of my head, so please
forgive any minor errors/typos. The general structure is the idea I'm
trying to get across.
I have used a structure very similar to the code below, with good
results. I know it's not the only way to do things, but it has served me
well.
--John
my_servlet.py
--------------
# my_servlet.py could also be a psp page, I'm sure, but since I don't
really have any experience with psp...
from WebKit.Page import Page
from some.other.place import MyGenericAPI # a facade class that offers a
static API for business logic
class my_servlet(Page):
# preAction and postAction are changed to ensure that actions don't
write anything out to the screen (they just set state for writeHTML())
def preAction(self,name):
pass
def postAction(self):
self.writeHTML()
def actions(self):
return Page.actions() + ['login']
def login(self):
login_id = self.request().fields().get('login_id','').strip()
passwd = self.request().fields().get('login_pw','').strip()
api = MyGenericAPI() # this could be implemented in some site
page as an attribute of the class
good_login,err_msg = api.VerifyLogin(login_id,passwd)
if good_login is True:
# use sendRedirectAndEnd so that we won't call writeHTML again
self.response().sendRedirectAndEnd('the_next_page_after_login.py')
else:
self.displayMessage = err_msg # this could be more elegant,
but this is an example, right?
# this action will now fall out to writeHTML
def writeContent(self):
# best way:
#render_template_for_this_page(self.displayMessage,blah,blah,whatever)
# slightly more straightforward but harder to maintain way:
# (I've left out the css niceties, etc)
wl = self.writeln
if self.displayMessage != "":
wl('Error: %s' % self.displayMessage)
wl('<form action="my_servlet.py" method="post">')
wl('Login ID:<input type="text" name="login_id" />')
wl('Password:<input type="password" name="login_pw" />')
wl('<input type="submit" name="_action_login" value="Log Me In!" />')
wl('</form>')
some.other.place.py
--------------------
import login_mod
class MyGenericAPI(object):
# the implementation of these functions may change, but the
functions themselves should not change much (if ever)
def VerifyLogin(self,login_id,pw):
return login_mod.verify(login_id,pw)
login_mod.py
-------------
import storage_mod
class login_class(object):
user_id = None
passwd = None
def load(which):
return storage_mod.load(which)
def save(which,where):
storage_mod.save(which,where)
def verify(some_id,some_pw):
login_class_instance = storage_mod.load(some_id)
if login_class_instance.passwd == some_hash(some_pw):
return true
else:
return false
storage_mod.py
---------------
# whatever storage method you are using, but basically, this is a common
gateway for all storage stuff (like MyGenericAPI above)
import magic
def load(request):
return magic.sprinkles(request)
def save(which,where):
magic.pixie_dust(which,where)
maker joe wrote:
> hi john,
> can i have a simple CRUD code example to see how it looks like ?
> kind regards
> makerjoe
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