Webware for Python

The way to understand Webware is through the source.

You are looking for setting and gettting session data

Take a look at the summary for WebKit.page
http://webware.sourceforge.net/Webware-0.7/WebKit/Docs/Source/Summaries/Page.py.html

You will see a method called session.  this will return the session 
ovject associated with the browser being used to access the page.

1) mySession = self.sessions()

Then you take a look at the docs for session
http://webware.sourceforge.net/Webware-0.7/WebKit/Docs/Source/Summaries/Session.py.html

and you will see hasValue, setValue, and value methods

So to set a session value use
mySession.setValue('pageCount',count)

to read it use:
mySession.hasValue('pageCount'):
	savedCount = mySession.value('pageCount')
else:
	savedCount = 0

Good Luck,
-Aaron Held


Ben Logan wrote:
> Hello,
> 
> I successfully installed Webware on my Redhat 7.1 box a few days ago,
> but am having some trouble with a few concepts.  Before I get into
> that, perhaps I should tell you what I would eventually like to
> accomplish using Webware.
> 
> I created and maintain a website at http://cyclist.wblogan.net.  You
> might want to take a look to get a feel for what I would like to do.
> My username is 'benl', and you can login with the pulldown menu on the
> left.  The site is written in PHP with a MySQL backend.  This was my
> first such project, and it shows!  :)  The code is nasty and
> unmaintainable, and the interface is crummy.  I do have an improved
> version in the works on my own system, but I've pretty much ceased
> work on it.  The new version is about 10,000 combined lines of
> PHP+HTML, and has a much more modular and layered design.  However, I
> would *much* rather code this project in Python.  It looks like
> WebWare could simplify the process for me.  Is this a good candidate
> for an application server?  If I'm understanding the concept behind an
> app server, the state of my application could remain intact between
> pages without me having to try to maintain it between pages.  That's
> what I've been using sessions in PHP for, but it always seems to get
> complicated--especially when it comes to accepting/validating form
> data.  Or maybe I'm just dense...
> 
> I think I get most of the ideas from the examples provided with WebKit
> (and looking through the sources), but I'm mainly confused about
> transactions and the HTTP{Request,Response} classes.  (OK, so there
> are a bunch more that I don't get, but those seem most relevant.)  I'm
> just having some trouble getting started with WebKit--probably because
> I'm completely new to appservers in general.
> 
> I hope I've made my question clear.  Thanks for any help,
> 
> Ben
>

On Thu, 2002-09-26 at 13:33, Ben Logan wrote:
> Hello,
> 
> I successfully installed Webware on my Redhat 7.1 box a few days ago,
> but am having some trouble with a few concepts.  Before I get into
> that, perhaps I should tell you what I would eventually like to
> accomplish using Webware.
> 
> I created and maintain a website at http://cyclist.wblogan.net.  You
> might want to take a look to get a feel for what I would like to do.
> My username is 'benl', and you can login with the pulldown menu on the
> left.  The site is written in PHP with a MySQL backend.  This was my
> first such project, and it shows!  :)  The code is nasty and
> unmaintainable, and the interface is crummy.  I do have an improved
> version in the works on my own system, but I've pretty much ceased
> work on it.  The new version is about 10,000 combined lines of
> PHP+HTML, and has a much more modular and layered design.  However, I
> would *much* rather code this project in Python.  It looks like
> WebWare could simplify the process for me.  Is this a good candidate
> for an application server?  If I'm understanding the concept behind an
> app server, the state of my application could remain intact between
> pages without me having to try to maintain it between pages.  That's
> what I've been using sessions in PHP for, but it always seems to get
> complicated--especially when it comes to accepting/validating form
> data.  Or maybe I'm just dense...

Yes, Webware would be appropriate for this sort of application.  It's
still similar to PHP in terms of session data, but hopefully it would
still be simpler.  I'd recommend you spend time putting all the hard
work (with the databases and statistics generation) into a plain Python
module (i.e., one that doesn't use Webware in any way).  Then you can
use Webware servlets to provide an interface to this module.  This will
help keep your code cleaner, and probably make the programming more
pleasant.  

> I think I get most of the ideas from the examples provided with WebKit
> (and looking through the sources), but I'm mainly confused about
> transactions and the HTTP{Request,Response} classes.  (OK, so there
> are a bunch more that I don't get, but those seem most relevant.)  I'm
> just having some trouble getting started with WebKit--probably because
> I'm completely new to appservers in general.

Maybe you are thinking there is more to those objects than there really
is.  They are actually quite simple objects -- Transaction is just a
holder for the HTTPRequest and HTTPResponse.  The request and response
just hold input (form fields) and output (headers, cookies, and the body
of the page).  If you want to get a feel for how WebKit as a whole
works, you might look at
http://webware.colorstudy.net/twiki/bin/view/Webware/TransactionAnatomy
-- however, you don't need to get to this depth to use WebKit (but it
might make you more comfortable with what's going on).

  Ian

On Thu, Sep 26, 2002 at 02:42:11PM -0500, Ian Bicking wrote:
> > If I'm understanding the concept behind an
> > app server, the state of my application could remain intact between
> > pages without me having to try to maintain it between pages.  That's
> > what I've been using sessions in PHP for, but it always seems to get
> > complicated--especially when it comes to accepting/validating form
> > data.  Or maybe I'm just dense...
> 
> Yes, Webware would be appropriate for this sort of application.  It's
> still similar to PHP in terms of session data, but hopefully it would
> still be simpler.  I'd recommend you spend time putting all the hard
> work (with the databases and statistics generation) into a plain Python
> module (i.e., one that doesn't use Webware in any way).  Then you can
> use Webware servlets to provide an interface to this module.  This will
> help keep your code cleaner, and probably make the programming more
> pleasant.  

There are two types of application data.  Data that depends on the
current user has to be kept in session variables like PHP because the
appserver is handling several users at once, and the only way to tell
that this transaction is related to a previous transaction is if they
have a common session ID.  

But there's another type of application data, that which doesn't depend
on the current user.  Perhaps it's an array of error messages or cached
data.  With PHP, you'd have to reinitialize it from source every 
transaction.  With an application server, you can store them in module
globals as Ian suggests, and they are "already there" for the next
transaction.  That's the kind of state Webware gives you that PHP
doesn't.

-- 
-Mike (Iron) Orr, iron@...  (if mail problems: mso@...)
   http://iron.cx/     English * Esperanto * Russkiy * Deutsch * Espan~ol

On Thu, Sep 26, 2002 at 02:42:11PM -0500, Ian Bicking wrote:
[...]
> Yes, Webware would be appropriate for this sort of application.  It's
> still similar to PHP in terms of session data, but hopefully it would
> still be simpler.  I'd recommend you spend time putting all the hard
> work (with the databases and statistics generation) into a plain Python
> module (i.e., one that doesn't use Webware in any way).  Then you can
> use Webware servlets to provide an interface to this module.  This will
> help keep your code cleaner, and probably make the programming more
> pleasant.  

I would really like to design the program that way, because I would
also like to have a compatible, non-web version (perhaps with wxPython
or even ncurses as an interface).  Ideally, there would be a module
that could be hooked with any UI desired.

One question I have is regarding how to store my data in the database.
The records I'm dealing with could be nicely represented by a set of
interrelated Python objects.  Is it better to simply pickle these
objects and store the results in the SQL database, or better to
rebuild the objects from the database rows each time the data is
retrieved?
 
> > I think I get most of the ideas from the examples provided with WebKit
> > (and looking through the sources), but I'm mainly confused about
> > transactions and the HTTP{Request,Response} classes.  (OK, so there
> > are a bunch more that I don't get, but those seem most relevant.)  I'm
> > just having some trouble getting started with WebKit--probably because
> > I'm completely new to appservers in general.
> 
> Maybe you are thinking there is more to those objects than there really
> is.  They are actually quite simple objects -- Transaction is just a
> holder for the HTTPRequest and HTTPResponse.  The request and response
> just hold input (form fields) and output (headers, cookies, and the body
> of the page).  If you want to get a feel for how WebKit as a whole
> works, you might look at
> http://webware.colorstudy.net/twiki/bin/view/Webware/TransactionAnatomy

Okay, I think I'm getting the picture now.  I was trying to make
Transactions more complicated than they are.
 
Thanks to all who responded (Aaron, Ian, and Mike),

Ben

-- 
Ben Logan: ben at wblogan dot net
OpenPGP Key KeyID: A1ADD1F0

We don't need no education, we don't need no thought control.
		-- Pink Floyd

> One question I have is regarding how to store my data in the database.
> The records I'm dealing with could be nicely represented by a set of
> interrelated Python objects.  Is it better to simply pickle these
> objects and store the results in the SQL database, or better to
> rebuild the objects from the database rows each time the data is
> retrieved?

This is really application specific, but here is what I did on some 
projects:

User information is stored in related tables and I query a db view to 
pull in all of the required info about a user (preferences, security 
level etc...) Then I build an instance of a user class and stick that 
into a session as a py object.

News Articles were stored in a db but I used a python object to sql 
mapping (MiddleKit) to allow me to work with objects.  I called 
articles.save() and then the mapping writes and executed the required sql.

Application settings are stored in a py module as a python dict.  This 
never changes during an application run, so it is used a module variable.

 From mySettings import Settings
self.writeln( 'Welcome to app version' % Settings.version )

I like using a db table because I can manipulate the data outside of 
python, but using native objects is easier.  It really depends upon how 
you will aquire the data also.

-Aaron

On Fri, Sep 27, 2002 at 08:11:17AM -0400, Ben Logan wrote:
> One question I have is regarding how to store my data in the database.
> The records I'm dealing with could be nicely represented by a set of
> interrelated Python objects.  Is it better to simply pickle these
> objects and store the results in the SQL database, or better to
> rebuild the objects from the database rows each time the data is
> retrieved?

There's no "right" answer, but I would be inclined to bust them down
into normal SQL objects.  That way you have a second way to access
the data (the *SQL CLI) if you need to repair something, and the data
is also portable to a non-Python application if the need should
ever arise.  

This assumes the data can be conveniently represented as:
1) A row of SQL objects (strings, numbers, date fields...)
2) Rows in related tables with a common key field linking them
3) A table with 'key' & 'value' columns (or maybe 'section', 'key' &
   'value').

If not, then maybe you want to keep the data together in Pickle
units rather than breaking it down further.  At that point, you can
investigate ZODB, which automatically does the (un)pickling for you
using an intuitive get-database-object, use-dotted-fields-and-the-
assignment-operator-to-review/update-the-data, call-a-commit-method
interface.  It doesn't do everything a SQL database does; in
particular I don't think it handles multiple processes accessing the
database simultaneously (as opposed to a multithreaded Webware
application which is one process); but supposedly ZEO does such
multiplexing.

-- 
-Mike (Iron) Orr, iron@...  (if mail problems: mso@...)
   http://iron.cx/     English * Esperanto * Russkiy * Deutsch * Espan~ol

On Fri, 2002-09-27 at 07:11, Ben Logan wrote:
> On Thu, Sep 26, 2002 at 02:42:11PM -0500, Ian Bicking wrote:
> [...]
> > Yes, Webware would be appropriate for this sort of application.  It's
> > still similar to PHP in terms of session data, but hopefully it would
> > still be simpler.  I'd recommend you spend time putting all the hard
> > work (with the databases and statistics generation) into a plain Python
> > module (i.e., one that doesn't use Webware in any way).  Then you can
> > use Webware servlets to provide an interface to this module.  This will
> > help keep your code cleaner, and probably make the programming more
> > pleasant.  
> 
> I would really like to design the program that way, because I would
> also like to have a compatible, non-web version (perhaps with wxPython
> or even ncurses as an interface).  Ideally, there would be a module
> that could be hooked with any UI desired.
> 
> One question I have is regarding how to store my data in the database.
> The records I'm dealing with could be nicely represented by a set of
> interrelated Python objects.  Is it better to simply pickle these
> objects and store the results in the SQL database, or better to
> rebuild the objects from the database rows each time the data is
> retrieved?

If you want something to help you rebuild your objects, you are looking
for an Object Relational Mapper -- there are several out there. 
MiddleKit, included with Webware, is one of them (it doesn't actually
have any Webware dependencies, though, so you can use it without
Webware).  There's lots of others, as well.

ZODB will take care of the pickling if you like, but you can also do it
yourself if you don't have much data that needs to be persistent like
this.  I often use pickle for small parts of the data that don't
translate well to SQL (often runtime extensible objects).

BTW -- you should also consider using XMLRPC for alternate interfaces. 
Then you are still location-independent, but don't have to put
everything through a browser.  It's very easy to work with, both client
and server (see XMLRPCServlet in Webware for the server side).

  Ian