[Zope3-dev] IMPORTANT RFS: Through the Web Site Development

[Jim Fulton]

Stephan Richter wrote:

...

> What I noticed is that we will have an awesome system for people that know 
> Python and understand the CA.
> 
> On the other hand we will loose about 70-80% (wild guess) of the current Zope 
> 2 TTW developers, who do not know any Python and have difficulties to 
> understand it.

That is a wild guess. I wish I knew what the real numbers were.

One wonders what they *do* know, if not Python .... of course,
you answer that below....

 > I am pretty sure that there are many, many sites out there
> that are written using one of the following two options:
> 
> 1.) They only use the standard Content Objects that are provided by default in 
> Zope 2 (maybe they download another product or two). Then they use ZPT and 
> DTML to do all the logic. Note: I do not think that much Python Script is 
> used unless someone on the mailing list gave it to them.

So they don't know Python, but they *do* know dtml and zpt.  Certainly,
they have to *learn* these to use Zope.  Of course, we're being pretty vague
about what we mean by logic.

Any non-display logic in DTML or ZPT is Python, so they are probably using some Python
anyway. But maybe you are talking about people who just do simpler interaction,
conditionals and data insertion.

I think that this group of users is best served by content-space scripts and pages.

> 2.) They use ZClasses (because they understand sort of OO programming) and use 
> scripts often DTML and ZPT, but maybe already some very small Python scripts 
> to do the logic.

Well, if they use ZClasses, they are forced to deal with class, products,
methods, and either Python, or some hairy DTML or ZPT logic.

> Advanced Zope developers use:
> 
> 3) They write their own Python products, but develop most of the look and feel 
> using the ZMI and therefore ZPT and DTML that lives in the ZODB.
> 
> While I think that group 3 is addressed nicely, Group 1 and 2 are not.

I don't think your group 2 is well served by ZClasses. I think that they
are better served with something like the system I've sketched out.
If they don't need any Python logic, or insist on only using Python
scripts in their templates, they can work solely with ZPT (or DTML if we
decide we need that).

If they do need Python, they's be much better off creating modules.
Modules are pretty simple, after all.

 > The
> current versions of ZPT Page and DTML Page are too weak (as intended when 
> originally implmented) to satisfy group 1, since you do not have access to 
> some of the interesting methods.

What methods to they not have access to? Could you be more specific?


> Example: I want to create a menu quickly. What I did on one site was to simply 
> take an OrderedFolder and put other OrderedFolder objects in it having a 
> senible title. Then I just called "of.objectValues('Ordered Folder')" and 
> displayed the titles of the sub-folders an voila I had my menu. This was a 
> 2-minute task. How would I do that in Zope 3?

We don't have an API like objectValues, that filteres items that have a particular
type.  If all of the items in the outer folder were known to be ordered folders,
you could just use the values method: "of.values()", or, better yet: "of/values"

If people need an API like that (I'm a bit skeptical), then someone could
certainly provide one.

> Addressing Group 2, let's say I want to quickly create a NewsItem object that 
> has a couple of properties and methods. In Zope 2 I would just create a 
> ZClass, add all the properties and create a couple of scripts for the methods 
> and I am done. If ZClasses weren't so unpredictable, this should be a 
> 10-minute task. How would I do that in Zope 3? Note that writing a Python 
> module is **not** an option.

Could you explain why creating a module is not an option? If people are
using Python anyway, wouldn't it make more sense to have them create something
familiar, like a Python class in a module?

> What I want to do is:
> 
> 1. Create ContentObject that inherits from this and that.

Like what and which? Do you really think the non-advanced user
cares that much about inheritence?

> 2. Create properties in Content Object.

These are most simply done in a Python module.

> 3. Create methods in Content Object.

Ditto

> 4. Define security.

You'll be able to do that with content configuration in a way that's
*much* simpler than ZClasses.

> 5. Register the Content Object.

Yes, this too will be much cleaner than with ZClasses.

> A more Zope3ish way would be to define the interface doing step 1-3 and then 
> autogenerate the Content Object skeleton. 

We could certainly provide a tool like this.  Steve and Martijn
are working on a system for generating content types from schema.

Their system generates Python modules that implement the schema.

Jim

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