On Jun 4, 10:43 am, Doug Warren <[email protected]> wrote: > Traditionally when I've written MVC style applications, the model > would contain not only the data representing the objects but also the > data for manipulating the objects. I'm not sure how that same > relation applies to web2py. > > If I have a model that defines 4-5 tables, 2 of them are just foreign > key lookups, and creating a new object involves inserting data into 3 > of the tables, it seems that I would want a create_object method in my > model file. > > So I write something like: > > def create_object(owner_id=None, template=None): > # Some sanity checking on the above > new_object = db.objects.insert(template_id=template.id, > person_id=owner_id) > > widgets = db.template_widget(db.template_widget.thingy_template_id > == template.id).select() > for widget in widgets: db.thingy_widget.insert(widget_id = > widget.id, thingy_id = new_object) > > whatchymacallits = > db.template_whatchymacallit(db.template_whatchymacallit.thingy_template_id > == template.id).select() > for whatchymacallit in whatchymacallits: > db.thingy_whatchymacallit.insert(whatchymacallit_id = > whatchymacallit.id, thingy_id = new_object) > > return new_object > > and place that into my db.py. Now the controller has a function like: > def create(): > form = SQLFORM.factory( Field('template', > requires=IS_IN_SET(__get_templates()))) > if form.accepts(request.vars, session): > foo = db.create_object(owner_id=auth.auth_id, > template_name=form.vars.template) > response.flash = "Created" > elif form.errors: > response.flash = "Error (hacker)" > > Well db is referring to the DAL db not the db.py, from db import > create_object gives a name not found error, so I'm at a loss as to how > to define functions that work upon the model and can be invoked from > one or more controllers.
I'm not sure what exactly you are saying here - but to import, use local_import() (see http://www.web2py.com/book/default/section/4/18?search=local_import) BUT before you do, here is some background: When a request comes into web2py, here's what happens (roughly): web2py parses the request url, and sets up an environment to call the appropriate application / controller / function; Part of that setup involves running all the files in your app's model folder (so that db connections, table definitions, etc. are all "there for you"); This means you can put your files in the models folder, and they will be run (defined) before the call to your controller. Then, your controller / function is called. local_import will pull in definitions / modules from your application's modules folder, but you can (for development certainly) just put your file in your models folder. When you really want to reduce what gets run at _each_ request, you might want to look at what to move to modules, so that you're only pulling in those files when needed. As for db - DAL: db is the "global" and "default" name for the db connection string (it is so named and setup in the default models/ db.py file). You can change the name of this variable as you like (or change your imports). Hope this at least helps point you out of the forrest. Regards, - Yarko > Are there any non-trivial example > applications for web2py? Most of the ones that I have seen assumes > that all data you need in the database can be supplied from a form and > that's not the case I run into over and over again.
