pyPgSQL/Quixote data cursor browse form

	Here is my first cut at a usable data table browser implemented as a Quixote form (hack). 
Not being too intimate with the guts of pyPgSQL or Quixote, I find it works pretty well and doesn't 
have too many nasty surprises. I'd be VERY curious as to comments or recommendations on how 
to accomplish the same functionality in a more correct or elegant manner. 

	All that's needed to try the thing out is to instantiate an instance of DataTableForm, 
passing it a cursor that has executed its SQL statement. This will provide you with a page of 'X' 
rows (optional __init__ parm defaults to 10) of your data with an additional header row listing each 
field name. The data is strictly read-only although the fields appear to be editable - no changes will 
make it to the database (doesn't HTML allow you to specifiy an "input" as non-editable?).

	The other neat hack that I implemented is the ability to optionally filter your data. If you 
also pass in the select statement text (with the where clause eliminated and any where predicates 
in a seperate string if needed), under each column header will be a blank input field (our form's 
actual text widgets) and a new "Filter" button to the left of the table which, when pressed, will take 
the contents of the entry widgets and apply them as a new where clause (which will get stuck 
between the select string and the predicate string which is why I make you seperate them) against 
your cursor. This trick is a bit too invasive for my taste and I'm thinking of passing the filtering tuples 
into a callback function (so the form can be completely ignorant of the SQL) that handles the 
database but haven't decided the best way to do this. I found it interesting (ok - a bit frustrating) 
when implementing this, that, if you manually generate a submit button in your html output, but there 
is not a matching submit_button_widget instance in your form with the same name - selecting it will 
reload the form but your action method will never be called. As a result, you'll see the "Filter" submit 
present twice on the form... One thing I'd like to do is put an Edit or Select submit_button to the left 
of each row of data and have it do something useful but I don't want to use javascript (if I can 
avoid it) and don't want to add a button for each row along the bottom as I have for Filter.

	My first pass at this had me reimplementing several of the Form methods but I finally 
figured out enough about how the form works to cut this way back to just  
__render_visible_widgets() and a few supporting methods so that I don't groan too much when 
considering the structure. I get the feeling I probably could have handled the table content field 
generation a little cleaner but my attempts always hit a snag so I just took complete control over it.

	So has anyone else tried to implement something like this within Quixote? Does my 
implementation show a complete ignorance of the framework's purpose or is this pretty much how 
it's done? 

	One last thing I noticed is that pyPgSQL reports a size of 4 for integer types which is 
really bad because this means I can't enter in a filter of greater than 4 characters for integer fields. 
This comes from the cursor.decription of the select results. Anyone recommend a good way to deal 
with this? Is it a pyPgSQL anomoly or is the 4 supposed to be interpreted differently for integers?

	many thanx,

		Ben Scherrey

_______________________________________________
Quixote-users mailing list
Quixote-users-fVcApmY9cLvQ3/1i3zOLAti2O/[email protected]
http://mail.mems-exchange.org/mailman/listinfo/quixote-users