From abulka at netspace.net.au  Fri Mar 14 10:05:21 2003
From: abulka at netspace.net.au (abulka at netspace.net.au)
Date: Fri, 14 Mar 2003 10:05:21 +1100
Subject: [albatross-users] file upload capability for Albatross
Message-ID: <1047596721.3e710eb1767d8@webmail.netspace.net.au>

Hi Dave,
 I like Albatross more and more...  

 On 21 Sep 2002 you wrote:

 "At some stage we will have to implement file upload capability for Albatross."

 Any idea when a new release with this capability will happen?  I want my users 
to upload text and images onto a single web page, and have that same web page 
appear immediately with the new images/comments - like a wikki.  Also hoping to 
avoid cache problems so that the new page is presented straight away.

 Should I make the change to a cgiapp.Request.field_value() as you recommended 
in an earlier post - and just go with that?  Would a new albatross release do 
any more for me?

thanks for any thoughts,
-Andy Bulka
http://www.atug.com/andypatterns




------------------------------------------------------------
This email was sent from Netspace Webmail: http://www.netspace.net.au



From andrewm at object-craft.com.au  Fri Mar 14 10:43:59 2003
From: andrewm at object-craft.com.au (Andrew McNamara)
Date: Fri, 14 Mar 2003 10:43:59 +1100
Subject: [albatross-users] file upload capability for Albatross 
In-Reply-To: Message from abulka@netspace.net.au 
   of "Fri, 14 Mar 2003 10:05:21 +1100." <1047596721.3e710eb1767d8@webmail.netspace.net.au> 
References: <1047596721.3e710eb1767d8@webmail.netspace.net.au> 
Message-ID: <20030313234359.572893CC5F@coffee.object-craft.com.au>

> "At some stage we will have to implement file upload capability for
> Albatross."
>
> Any idea when a new release with this capability will happen?

We needed this recently ourselves - this is one of the changes that is
waiting for us to get off our butt and release a new albatross.

Note to self - need to add example type="file" use to doco.

The changelog entry reads:

    Added support for <input type="file">. For inputs of this sort, the
    local context now gets a list of FileField instances. The FileField
    class contains attributes for filename (filename), open file object
    (file), and mime type (type).

    The NameRecorder Mixin tracks whether a type="file" input has
    been seen, and the to_html method of the Form class generates the
    appropriate enctype attribute if seen (otherwise file inputs simply
    pass back the filename).

    On type="file" inputs, "value" attributes are now ignored.

    Currently this is only supported on the cgiapp request class, and
    no documentation or tests have been written.

> Should I make the change to a cgiapp.Request.field_value() as you recommended 
>in an earlier post - and just go with that?  Would a new albatross release do 
>any more for me?

The changes were recently involved, and I'm sure the diff won't apply
cleanly to the 1.01 release. For information purposes only (you probably
don't want to try to apply it unless you're really desperate):

cvs server: Diffing .
Index: cgiapp.py
===================================================================
RCS file: /usr/local/cvsroot/object-craft/albatross/albatross/cgiapp.py,v
retrieving revision 1.28
retrieving revision 1.30
diff -u -r1.28 -r1.30
--- cgiapp.py   29 Nov 2002 10:12:47 -0000      1.28
+++ cgiapp.py   11 Dec 2002 05:08:00 -0000      1.30
@@ -5,9 +5,21 @@
 #
 import cgi, sys, os, string
 
+class FileField:
+    def __init__(self, field):
+        self.filename = field.filename
+        self.file = field.file
+        self.type = field.type
+
+    def __repr__(self):
+        return 'FileField(%s, %s, %s)' % (self.filename, self.file, self.type)
+
 class Request:
-    def __init__(self):
-        self.__fields = cgi.FieldStorage()
+    def __init__(self, fields = None):
+        if fields:
+            self.__fields = fields
+        else:
+            self.__fields = cgi.FieldStorage()
         self.__sent_headers = 0
         self.__status = 200
 
@@ -16,12 +28,18 @@
 
     def field_value(self, name):
         field = self.__fields[name]
-        if type(field) is type([]):
-            value = []
-            for elem in field:
-                value.append(elem.value)
-            return value
+        if isinstance(field, type([])):
+            return map(lambda f: f.value, field)
         return field.value
+
+    def field_file(self, name):
+        field = self.__fields[name]
+        if isinstance(field, type([])):
+            return map(FileField, field)
+        if field.type[:9] == 'multipart':
+            return map(FileField, field.value)
+        else:
+            return [FileField(field)]
 
     def field_names(self):
         return self.__fields.keys()
Index: context.py
===================================================================
RCS file: /usr/local/cvsroot/object-craft/albatross/albatross/context.py,v
retrieving revision 1.72
retrieving revision 1.73
diff -u -r1.72 -r1.73
--- context.py  6 Dec 2002 07:06:34 -0000       1.72
+++ context.py  11 Dec 2002 04:10:48 -0000      1.73
@@ -229,11 +229,14 @@
         return '(%s,%s)' % (self.x, self.y)
 
 class NameRecorderMixin:
+    NORMAL, LIST, FILE = range(3)
+
     def __init__(self):
         self.__elem_names = {}
 
     def form_open(self):
         self.__elem_names = {}
+        self.__need_multipart_enc = 0
 
     def form_close(self):
         text = cPickle.dumps(self.__elem_names, 1)
@@ -245,9 +248,13 @@
         self.write_content(text)
         self.write_content('">\n')
         self.__elem_names = {}
+        return self.__need_multipart_enc
 
     def input_add(self, itype, name, unused_value = None, return_list = 0):
-        if self.__elem_names.has_key(name):
+        if itype == 'file':
+            self.__need_multipart_enc = 1
+            self.__elem_names[name] = self.FILE
+        elif self.__elem_names.has_key(name):
             prev_multiples = self.__elem_names[name]
             implicit_multi = itype in ('radio', 'submit', 'image')
             if not return_list and not implicit_multi:
@@ -261,7 +268,10 @@
                 raise FieldTypeError('"%s" initially defined as "list"' % \
                                      name)
         else:
-            self.__elem_names[name] = return_list
+            if return_list:
+                self.__elem_names[name] = self.LIST
+            else:
+                self.__elem_names[name] = self.NORMAL
 
     def merge_request(self):
         if not self.request.has_field('__albform__'):
@@ -277,8 +287,10 @@
         if not text:
             return
         elem_names = cPickle.loads(text)
-        for name, return_list in elem_names.items():
-            if self.request.has_field(name):
+        for name, mode in elem_names.items():
+            if mode == self.FILE:
+                value = self.request.field_file(name)
+            elif self.request.has_field(name):
                 value = self.request.field_value(name)
             else:
                 x_name = '%s.x' % name
@@ -289,7 +301,7 @@
                                   int(self.request.field_value(y_name)))
                 else:
                     value = None
-            if return_list:
+            if mode == self.LIST:
                 if not value:
                     value = []
                 elif type(value) is not type([]):
Index: tags.py
===================================================================
RCS file: /usr/local/cvsroot/object-craft/albatross/albatross/tags.py,v
retrieving revision 1.100
retrieving revision 1.102
diff -u -r1.100 -r1.102
--- tags.py     18 Nov 2002 23:18:39 -0000      1.100
+++ tags.py     11 Dec 2002 04:10:48 -0000      1.102
@@ -149,18 +149,18 @@
             ctx.write_content(' checked')
         ctx.input_add('checkbox', name, value_attr, self.has_attrib('list'))
 
-    def image_to_html(self, ctx):
+    def generic_novalue_to_html(self, ctx):
         # value= not applicable
-        self.write_attribs_except(ctx)
+        self.write_attribs_except(ctx, 'value')
         name = self.get_name(ctx)
         ctx.write_content(' name="%s"' % name)
-        ctx.input_add('image', name, None, self.has_attrib('list'))
+        ctx.input_add(self.__itype, name, None, self.has_attrib('list'))
 
     type_dict = {
         'text': generic_to_html, 'password': generic_to_html,
         'radio': radio_to_html, 'checkbox': checkbox_to_html,
         'submit': generic_to_html, 'reset': generic_to_html,
-        'image': image_to_html, 'file': generic_to_html,
+        'image': generic_novalue_to_html, 'file': generic_novalue_to_html,
         'hidden': generic_to_html, 'button': generic_to_html, }
 
 # Allows the application need to modify the HREF attribute of the <A>
@@ -229,18 +229,27 @@
 # Using the albatross <FORM> tag allows Albatross to record the
 # contents of each form.  This is used to register valid browser
 # requests with the toolkit.
+#
+# We use a content_trap to capture the enclosed content so we know before
+# emiting the <form> element whether or not to use a multipart/form-data
+# encoding (required to make <input type="file"> work correctly).
 class Form(EnclosingTag):
     name = 'al-form'
 
     def to_html(self, ctx):
+        ctx.push_content_trap()
+        ctx.form_open()
+        EnclosingTag.to_html(self, ctx)
+        use_multipart_enc = ctx.form_close()
+        content = ctx.pop_content_trap()
         ctx.write_content('<form')
         self.write_attribs_except(ctx)
         if not self.has_attrib('action'):
             ctx.write_content(' action="%s"' % ctx.current_url())
+        if use_multipart_enc and not self.has_attrib('enctype'):
+            ctx.write_content(' enctype="multipart/form-data"')
         ctx.write_content('>')
-        ctx.form_open()
-        EnclosingTag.to_html(self, ctx)
-        ctx.form_close()
+        ctx.write_content(content)
         ctx.write_content('</form>')
 
 # Applications which need to know the list of valid <al-select>
@@ -250,6 +259,10 @@
 # Two forms implemented:
 # <al-option>12</al-option>
 # <al-option value="12">Arbitrary text</al-option>
+# 
+# In the first form, we need to evaluate the content of the tag before
+# we output the start tag so we can determine whether or not to set
+# the selected attribute on the option, hence the use of the content_trap.
 class Option(EnclosingTag):
     name = 'al-option'


-- 
Andrew McNamara, Senior Developer, Object Craft
http://www.object-craft.com.au/


From andrewm at object-craft.com.au  Fri Mar 14 11:04:35 2003
From: andrewm at object-craft.com.au (Andrew McNamara)
Date: Fri, 14 Mar 2003 11:04:35 +1100
Subject: [albatross-users] file upload capability for Albatross 
In-Reply-To: Message from Andrew McNamara <andrewm@object-craft.com.au> 
   of "Fri, 14 Mar 2003 10:43:59 +1100." <20030313234359.572893CC5F@coffee.object-craft.com.au> 
References: <1047596721.3e710eb1767d8@webmail.netspace.net.au>  <20030313234359.572893CC5F@coffee.object-craft.com.au> 
Message-ID: <20030314000435.573873CC5F@coffee.object-craft.com.au>

>The changes were recently involved, and I'm sure the diff won't apply

That should have been "were reasonably involved" - my fingers were off
doing their own thing again.

-- 
Andrew McNamara, Senior Developer, Object Craft
http://www.object-craft.com.au/


From abulka at netspace.net.au  Mon Mar 17 15:30:14 2003
From: abulka at netspace.net.au (abulka at netspace.net.au)
Date: Mon, 17 Mar 2003 15:30:14 +1100
Subject: [albatross-users] URL style user inputs requiring a session server
Message-ID: <1047875414.3e754f56d70d3@webmail.netspace.net.au>

I'm having trouble running the popview3 example.

1. I copied the file session-server/simpleserver.py 
into the popview3 directory, ran it and then entered
   http://localhost:34343/popview.py
into my browser.  This doesn't work - what are the 
correct instructions for running the popview3 example?

2. It seems that in order to have an albatross app be 
responsive to URL style user inputs, like popview3, 
e.g. <a href="magic?nextpage,m=1">Next Page</a> then 
one needs to run an albatross session server.  Doesn't
this mean that I cannot deploy on my regular obscure 
overseas ISP since they won't let me run my own server, 
let alone have my own port?

3. Is there any documentation or quick overview of 
what each part of URL style user inputs, mean to 
albatross? e.g.
 e.g. <a href="magic?nextpage,m=1">Next Page</a>
What exact bit of my web app code is executed when a user 
clicks on such an url?  How do I get at the url parameters
or does albatross make them available for me in some way?

If I had popview3 running I could probably deconstruct it
and figure out my question #3, however some simple 
documentation on this would be good. The doco on <al-a> tags
is great on creating these sorts of tags, but not on what
they mean.

thanks,
-Andy Bulka
http://www.atug.com/andypatterns







------------------------------------------------------------
This email was sent from Netspace Webmail: http://www.netspace.net.au



From andrewm at object-craft.com.au  Wed Mar 19 12:19:03 2003
From: andrewm at object-craft.com.au (Andrew McNamara)
Date: Wed, 19 Mar 2003 12:19:03 +1100
Subject: [albatross-users] URL style user inputs requiring a session server 
In-Reply-To: Message from abulka@netspace.net.au 
   of "Mon, 17 Mar 2003 15:30:14 +1100." <1047875414.3e754f56d70d3@webmail.netspace.net.au> 
References: <1047875414.3e754f56d70d3@webmail.netspace.net.au> 
Message-ID: <20030319011903.9D7433CC5F@coffee.object-craft.com.au>

>1. I copied the file session-server/simpleserver.py 
>into the popview3 directory, ran it and then entered
>   http://localhost:34343/popview.py
>into my browser.  This doesn't work - what are the 
>correct instructions for running the popview3 example?

The session server is a helper for the cgi, rather than being something
users access directly (the albatross application still runs under your
web server). You the session server with something like:

    al-session-daemon -l /tmp/al-ses.log -k /tmp/al-ses.pid start

You can also give it a -h option, and it will show you other arguments
that it accepts.

Once it is running, you should be able to use session-server based
albatross applications. Assuming that you had installed the popview3 sample
to your web server's cgi-bin directory, you would access it as:

    http://localhost/cgi-bin/popview3/popview.py

>2. It seems that in order to have an albatross app be 
>responsive to URL style user inputs, like popview3, 
>e.g. <a href="magic?nextpage,m=1">Next Page</a> then 
>one needs to run an albatross session server.  Doesn't
>this mean that I cannot deploy on my regular obscure 
>overseas ISP since they won't let me run my own server, 
>let alone have my own port?

You may find the session-file mixin more suitable in this case - it uses
files (by default in /tmp/<appname>) to record the session, rather than
passing the session to the session server.

>3. Is there any documentation or quick overview of 
>what each part of URL style user inputs, mean to 
>albatross? e.g.
> e.g. <a href="magic?nextpage,m=1">Next Page</a>
>What exact bit of my web app code is executed when a user 
>clicks on such an url?  How do I get at the url parameters
>or does albatross make them available for me in some way?

This is a special signal to the al-for iterator called "m", and isn't
passed directly to your application. Normally the al-for statement
iterates over all elements of the supplied list, but if you specify
the pagesize attribute, it will render the supplied list the specified
number of elements at a time, and the nextpage/prevpage stuff is used
to give the user control over which pagesized chunk of the list will be
rendered.

>If I had popview3 running I could probably deconstruct it
>and figure out my question #3, however some simple 
>documentation on this would be good. The doco on <al-a> tags
>is great on creating these sorts of tags, but not on what
>they mean.

Hope this helps.

-- 
Andrew McNamara, Senior Developer, Object Craft
http://www.object-craft.com.au/


From neel at mediapulse.com  Thu Mar 20 02:43:22 2003
From: neel at mediapulse.com (Michael C. Neel)
Date: Wed, 19 Mar 2003 10:43:22 -0500
Subject: [albatross-users] URL style user inputs requiring a session server
Message-ID: <C0FC22C08B82074A88B50061764157772C6555@johnson.mediapulse.net>

I'm not sure if this will help, but I'm messed around with CSS to create
a sumbit button to look like a hyperlink, so that I can have a link
submit a form (without resorting to javascript), and allow me to keep
the session in the hidden fields.

Mike

.btn { 
	font-family: Arial, Helvetica, sans-serif;
	font-size: 18px; color: #000000;
	border-style: none;
	background-color: #FFFFFF;
	text-decoration: underline;
	cursor: hand;
}

-----Original Message-----
From: abulka at netspace.net.au [mailto:abulka at netspace.net.au] 
Sent: Sunday, March 16, 2003 11:30 PM
To: albatross-users at object-craft.com.au
Subject: [albatross-users] URL style user inputs requiring a session
server


I'm having trouble running the popview3 example.

1. I copied the file session-server/simpleserver.py 
into the popview3 directory, ran it and then entered
   http://localhost:34343/popview.py
into my browser.  This doesn't work - what are the 
correct instructions for running the popview3 example?

2. It seems that in order to have an albatross app be 
responsive to URL style user inputs, like popview3, 
e.g. <a href="magic?nextpage,m=1">Next Page</a> then 
one needs to run an albatross session server.  Doesn't
this mean that I cannot deploy on my regular obscure 
overseas ISP since they won't let me run my own server, 
let alone have my own port?

3. Is there any documentation or quick overview of 
what each part of URL style user inputs, mean to 
albatross? e.g.
 e.g. <a href="magic?nextpage,m=1">Next Page</a>
What exact bit of my web app code is executed when a user 
clicks on such an url?  How do I get at the url parameters
or does albatross make them available for me in some way?

If I had popview3 running I could probably deconstruct it
and figure out my question #3, however some simple 
documentation on this would be good. The doco on <al-a> tags
is great on creating these sorts of tags, but not on what
they mean.

thanks,
-Andy Bulka
http://www.atug.com/andypatterns







------------------------------------------------------------
This email was sent from Netspace Webmail: http://www.netspace.net.au

_______________________________________________
Albatross-users mailing list Albatross-users at object-craft.com.au
https://www.object-craft.com.au/cgi-bin/mailman/listinfo/albatross-users


From andrewm at object-craft.com.au  Wed Mar 26 09:58:38 2003
From: andrewm at object-craft.com.au (Andrew McNamara)
Date: Wed, 26 Mar 2003 09:58:38 +1100
Subject: [albatross-users] URL style user inputs requiring a session server 
In-Reply-To: Message from "Michael C. Neel" <neel@mediapulse.com> 
   of "Wed, 19 Mar 2003 10:43:22 CDT." <C0FC22C08B82074A88B50061764157772C6555@johnson.mediapulse.net> 
References: <C0FC22C08B82074A88B50061764157772C6555@johnson.mediapulse.net> 
Message-ID: <20030325225838.E4E743C6F7@coffee.object-craft.com.au>

>I'm not sure if this will help, but I'm messed around with CSS to create
>a sumbit button to look like a hyperlink, so that I can have a link
>submit a form (without resorting to javascript), and allow me to keep
>the session in the hidden fields.
>
>Mike
>
>.btn {=20
>	font-family: Arial, Helvetica, sans-serif;
>	font-size: 18px; color: #000000;
>	border-style: none;
>	background-color: #FFFFFF;
>	text-decoration: underline;
>	cursor: hand;
>}

I couldn't get this to work when I tried it yesterday (with Opera and
Mozilla as browsers) - in particular, I can't see anything in the style
that would trigger the rendering of the button as a link. For the markup,
I was using something like:

    <al-input type="submit" class="btn" name="foo" value="bar">

-- 
Andrew McNamara, Senior Developer, Object Craft
http://www.object-craft.com.au/


From neel at mediapulse.com  Thu Mar 27 04:02:56 2003
From: neel at mediapulse.com (Michael C. Neel)
Date: Wed, 26 Mar 2003 12:02:56 -0500
Subject: [albatross-users] URL style user inputs requiring a session server 
Message-ID: <C0FC22C08B82074A88B50061764157772C6569@johnson.mediapulse.net>

I take it you are using linux browsers?  I haven't really checked the
style sheet there, as I'm mostly concerned with Windows systems.  In the
case where I've used this was on an Intranet, and it was IE only so
cross-platform wasn't an issue.  Try it in IE to make sure you have it
working (I'd just use a standard <input> to rule out an albatross
issues), then you can see if those browsers support enough css to make
this work.

Mike

-----Original Message-----
From: Andrew McNamara [mailto:andrewm at object-craft.com.au] 
Sent: Tuesday, March 25, 2003 5:59 PM
To: Michael C. Neel
Cc: albatross-users at object-craft.com.au
Subject: Re: [albatross-users] URL style user inputs requiring a session
server 


>I'm not sure if this will help, but I'm messed around with CSS to 
>create a sumbit button to look like a hyperlink, so that I can have a 
>link submit a form (without resorting to javascript), and allow me to 
>keep the session in the hidden fields.
>
>Mike
>
>.btn {=20
>	font-family: Arial, Helvetica, sans-serif;
>	font-size: 18px; color: #000000;
>	border-style: none;
>	background-color: #FFFFFF;
>	text-decoration: underline;
>	cursor: hand;
>}

I couldn't get this to work when I tried it yesterday (with Opera and
Mozilla as browsers) - in particular, I can't see anything in the style
that would trigger the rendering of the button as a link. For the
markup, I was using something like:

    <al-input type="submit" class="btn" name="foo" value="bar">

-- 
Andrew McNamara, Senior Developer, Object Craft
http://www.object-craft.com.au/


From francis.meyvis at sonycom.com  Thu Mar 27 22:59:33 2003
From: francis.meyvis at sonycom.com (Francis Meyvis)
Date: Thu, 27 Mar 2003 12:59:33 +0100
Subject: [albatross-users] problem with static data members in templates ...
Message-ID: <3E82E7A5.2080806@sonycom.com>

Hoi,

In a HTML form I present a database record/row data for editing.
The class cRow abstacts the db data.
The class in a simplified form is presented next:


class cRow():

   mFld = cField("table_name")

   def __init__(s, atData):
     mlData = list(atData)    # convert db query result tuple to list

   def __getitem__(s, i): return mlData[i]
   def __setitem__(s, i, v): mlData[i] = v

   def validate(): ... # validate the data in mlData
   def update(): ... # update database with changed mlData


cField is a static datamember to conserve memory
(it is the same for all rows of that specific table).
cField uses the DB API II ".description" to query the table format.
Using this information it adds datamembers to itself during __init__()
e.g.
mFld.mVal.NAME evaluates to a numberic index for
indexing the list "mlData" to find the value
corresponding to the column named 'NAME'


In the template I do something like this:

<al-input type="text" name="row[row.mFld.mVal.NAME]"/>

The idea was :-( that "row" is found in context.locals.
The advantage I saw, was that row's mlData is read and write
by albatross templating mechanism.
No need for me to start adding accessor functions.

But is does not work, I get the trace dump error below
(I use slight different variable names).

This could be a python 2.1 limitation however.
When I do a "dir(row)" I only see row's normal data members.
Not the static data member mFld.
In my python code (not template) itself this mechanism
for manipulating db data through cRow works.

Does someone on the list has a simple solution?

Many thanks,
francis




Template traceback (most recent call last):
   File "tmpl/prjAdd.html", line 34, in al-form
   <al-form method="post">
   File "tmpl/prjAdd.html", line 40, in al-input
         <td><al-input type="text" name="prjName" 
expr="xprj[xprj.mFld.mVal.OWNERID]"/></th>

Traceback (most recent call last):
   File "/usr/lib/python2.1/site-packages/albatross/app.py", line 147, 
in run
     self.display_response(ctx)
   File "/usr/lib/python2.1/site-packages/albatross/app.py", line 305, 
in display_response
     func(ctx)
   File "page/prjAdd.py", line 58, in page_display
     aoCtx.run_template(mode.GetTmplName(aoCtx))
   File "/usr/lib/python2.1/site-packages/albatross/app.py", line 65, in 
run_template
     templ.to_html(self)
   File "/usr/lib/python2.1/site-packages/albatross/template.py", line 
358, in to_html
     self.content.to_html(ctx)
   File "/usr/lib/python2.1/site-packages/albatross/template.py", line 
150, in to_html
     item.to_html(ctx)
   File "/usr/lib/python2.1/site-packages/albatross/tags.py", line 242, 
in to_html
     EnclosingTag.to_html(self, ctx)
   File "/usr/lib/python2.1/site-packages/albatross/template.py", line 
189, in to_html
     self.content.to_html(ctx)
   File "/usr/lib/python2.1/site-packages/albatross/template.py", line 
150, in to_html
     item.to_html(ctx)
   File "/usr/lib/python2.1/site-packages/albatross/tags.py", line 117, 
in to_html
     self.unbound_to_html(self, ctx)
   File "/usr/lib/python2.1/site-packages/albatross/tags.py", line 122, 
in generic_to_html
     name, value = self.get_name_and_value(ctx)
   File "/usr/lib/python2.1/site-packages/albatross/tags.py", line 90, 
in get_name_and_value
     return name, self.eval_expr(ctx)
   File "/usr/lib/python2.1/site-packages/albatross/tags.py", line 36, 
in eval_expr
     return ctx.eval_expr(self.expr)
   File "/usr/lib/python2.1/site-packages/albatross/context.py", line 
320, in eval_expr
     return eval(expr, self.__globals, self.locals.__dict__)
   File "<albatross>", line 0, in ?
AttributeError: mFld





From francis.meyvis at sonycom.com  Fri Mar 28 01:51:03 2003
From: francis.meyvis at sonycom.com (Francis Meyvis)
Date: Thu, 27 Mar 2003 15:51:03 +0100
Subject: [albatross-users] [Fwd: problem with static data members in templates ...]
Message-ID: <3E830FD7.3000803@sonycom.com>

Hoi,

Seems I made a scripting error that caused
the error described in my previous email.

However my problems with the idea are not gone.
When the post request from the form arrives I get the error
in context.py NamespaceMixin::set_value() described below.

I patched the method by adding an exception catch
in which I evaluate a statement "name = `value`".
Is there a danger doing so?
There's a big change someone can execute arbitrary code this way?

try:
   original code
except:
   vsStatement = name + "=" + `value` + "\n"
   exec vsStatement in self.locals.__dict__

Kind regards,
francis

Template traceback (most recent call last):

Traceback (most recent call last):
   File "lib/albatross/app.py", line 145, in run
     self.merge_request(ctx)
   File "lib/albatross/app.py", line 219, in merge_request
     ctx.merge_request()
   File "lib/albatross/context.py", line 297, in merge_request
     self.set_value(name, value)
   File "lib/albatross/context.py", line 355, in set_value
     index = int(elem)
ValueError: invalid literal for int(): prj



-------- Original Message --------
Subject: problem with static data members in templates ...
Date: Thu, 27 Mar 2003 12:59:33 +0100
From: Francis Meyvis <francis.meyvis at sonycom.com>
To: albatross-users at object-craft.com.au

Hoi,

In a HTML form I present a database record/row data for editing.
The class cRow abstacts the db data.
The class in a simplified form is presented next:


class cRow():

    mFld = cField("table_name")

    def __init__(s, atData):
      mlData = list(atData)    # convert db query result tuple to list

    def __getitem__(s, i): return mlData[i]
    def __setitem__(s, i, v): mlData[i] = v

    def validate(): ... # validate the data in mlData
    def update(): ... # update database with changed mlData


cField is a static datamember to conserve memory
(it is the same for all rows of that specific table).
cField uses the DB API II ".description" to query the table format.
Using this information it adds datamembers to itself during __init__()
e.g.
mFld.mVal.NAME evaluates to a numberic index for
indexing the list "mlData" to find the value
corresponding to the column named 'NAME'


In the template I do something like this:

<al-input type="text" name="row[row.mFld.mVal.NAME]"/>

The idea was :-( that "row" is found in context.locals.
The advantage I saw, was that row's mlData is read and write
by albatross templating mechanism.
No need for me to start adding accessor functions.

But is does not work, I get the trace dump error below
(I use slight different variable names).

This could be a python 2.1 limitation however.
When I do a "dir(row)" I only see row's normal data members.
Not the static data member mFld.
In my python code (not template) itself this mechanism
for manipulating db data through cRow works.

Does someone on the list has a simple solution?

Many thanks,
francis




Template traceback (most recent call last):
    File "tmpl/prjAdd.html", line 34, in al-form
    <al-form method="post">
    File "tmpl/prjAdd.html", line 40, in al-input
          <td><al-input type="text" name="prjName"
expr="xprj[xprj.mFld.mVal.OWNERID]"/></th>

Traceback (most recent call last):
    File "/usr/lib/python2.1/site-packages/albatross/app.py", line 147,
in run
      self.display_response(ctx)
    File "/usr/lib/python2.1/site-packages/albatross/app.py", line 305,
in display_response
      func(ctx)
    File "page/prjAdd.py", line 58, in page_display
      aoCtx.run_template(mode.GetTmplName(aoCtx))
    File "/usr/lib/python2.1/site-packages/albatross/app.py", line 65, in
run_template
      templ.to_html(self)
    File "/usr/lib/python2.1/site-packages/albatross/template.py", line
358, in to_html
      self.content.to_html(ctx)
    File "/usr/lib/python2.1/site-packages/albatross/template.py", line
150, in to_html
      item.to_html(ctx)
    File "/usr/lib/python2.1/site-packages/albatross/tags.py", line 242,
in to_html
      EnclosingTag.to_html(self, ctx)
    File "/usr/lib/python2.1/site-packages/albatross/template.py", line
189, in to_html
      self.content.to_html(ctx)
    File "/usr/lib/python2.1/site-packages/albatross/template.py", line
150, in to_html
      item.to_html(ctx)
    File "/usr/lib/python2.1/site-packages/albatross/tags.py", line 117,
in to_html
      self.unbound_to_html(self, ctx)
    File "/usr/lib/python2.1/site-packages/albatross/tags.py", line 122,
in generic_to_html
      name, value = self.get_name_and_value(ctx)
    File "/usr/lib/python2.1/site-packages/albatross/tags.py", line 90,
in get_name_and_value
      return name, self.eval_expr(ctx)
    File "/usr/lib/python2.1/site-packages/albatross/tags.py", line 36,
in eval_expr
      return ctx.eval_expr(self.expr)
    File "/usr/lib/python2.1/site-packages/albatross/context.py", line
320, in eval_expr
      return eval(expr, self.__globals, self.locals.__dict__)
    File "<albatross>", line 0, in ?
AttributeError: mFld






From djc at object-craft.com.au  Fri Mar 28 09:23:58 2003
From: djc at object-craft.com.au (Dave Cole)
Date: 28 Mar 2003 09:23:58 +1100
Subject: [albatross-users] [Fwd: problem with static data members in templates ...]
In-Reply-To: <3E830FD7.3000803@sonycom.com>
References: <3E830FD7.3000803@sonycom.com>
Message-ID: <m3isu4xxc1.fsf@ferret.object-craft.com.au>

> Seems I made a scripting error that caused the error described in my
> previous email.
> 
> However my problems with the idea are not gone.  When the post
> request from the form arrives I get the error in context.py
> NamespaceMixin::set_value() described below.

The parsing of input field names when merging requests is deliberately
limited to the following:

        name          ::= identifier | list-backdoor | tree-backdoor
        identifier    ::= identifier (("." identifier) | ("[" number "]"))*
        list-backdoor ::= operation "," iter
        tree-backdoor ::= operation "," iter "," alias

This is from the documentation:

        http://www.object-craft.com.au/projects/albatross/albatross/mixin-namespace.html

You could probably replace the:

        <al-input type="text" name="row[row.mFld.mVal.NAME]"/>

With:

        <al-input type="text" nameexpr="'row[%d]' % row.mFld.mVal.NAME"/>

This would make cause the template to generate input field with names
like row[0], row[1], etc.  The request merging will understand these
input field names.

- Dave

-- 
http://www.object-craft.com.au