Re: restrictedTraverse() and encapsulated image Codesource with VMH

Hi Heiko,

> my name is Heiko and I am the technical maintainer of  
> www.noordsee.de, a
> small website running Silva 2.1. Currently I am migrating content  
> from an
> older legacy website to a new publication within noordsee.de's root  
> folder
> and found a problem with code source encapsulated image using
> restrictedTraverse().
>
> For the setup (all absolute paths beginning from the Silva root:
>
> (1) /cms        # This is the noordsee.de's Silva root (virtual host
> monstered as www.noordsee.de)
> (2) /cms/watt   # This is the new publications root folder (currently
> vhm'ed as beta.noordsee.de, the folder is marked as virtual host  
> within
> Silva)
> (3) /cms/watt/pictures/test.jpg  # Here is my image object located
> (4) /cms/watt/watt_allgemein/gezeiten/sturmflut # Here I want to
> encapsulate an image found in (3)
>
> The problem I run into is when I want to link a code source  
> encapsulated
> image found in (3) to a Silva document found in (4). Code source  
> stores
> only "/pictures/test.jpg" as the image_path, whereas  
> restrictedTraverse()
> called from "/watt_allgemein/gezeiten/sturmflut" would need the  
> absolute
> path (3).
> This happends only for virtual hosts.

This code source has been around for a long time but you're right, it  
not working in virtual host situations when the image is not in the  
same folder or a lower folder as the doc. Fixing that is a tricky  
proposition. This issue created a lot of discussion, but no clean  
solution.

There is a workaround. When you use the 'get reference..." button  
while editing the code source, the lookup window returns a path from  
the virtual host root. In your case that is /pictures/test.jpg. If you  
manually add the missing path segments above the vhr, so the content  
of the image path field is:

/cms/watt//pictures/test.jpg

Then save the code source and save the doc, the encapsulated image  
should render properly.


> When I put as a workaound the image
> file within the same folder where the document is located it works ok.
> Nevertheless to get a more structured website a separate pictures  
> folder
> would be good.
>
> So my question to the folks the at silva-dev is how can I modify
> encapsulated image code source to get the full absolute path needed by
> restrictedTraverse()? Funny thing is that linking an image with the
> standard image koopu menu function Silva returns the full absolute  
> path.

With the image path there is some work done 'underwater', where the  
path from the vhr is saved, but removed when displaying to an author  
in the editor. Sometime authors don't know they're in a vh, and it  
could get confusing.

> On the code source site the fomulator view uses the following call to
> launch Silva object browser:
>
> (onclick event fired)
>
> reference.getReference(
> function(path, id, title) {
> document.getElementsByName('%(field_id)s')[0].value = path;;
> }, '%(url)s', 'Silva Image', true)
>
> Would it be clever to change the onclick function to use the same  
> function
> the standard image selector uses?

Both lookup windows store the same path segment. But for the image  
there's a modification on save. You can see this if you examine what's  
saved in the raw xml.

> Or would it be clever to modify the
> template file used by code source encapsulated image? There I found  
> the
> following line...
>
> ...
> imagepath    options/image_path;
> image        python: context.restrictedTraverse(str(imagepath));
> ...

If you have authors that shouldn't be bothered with the above  
workaround, we could do something like this:

...
vhostsegment  
python:get_not_yet_written_code_to_return_vhost_path_segment;
imagepath    options/image_path;
image        python: context.restrictedTraverse(str(vhostsegment +  
imagepath));
...

Actually there would have to be another step to make sure it works  
with relative urls too, where we only insert the vhostsegment if the  
path begins with a slash, but you get the idea....

Hope this helps,

Kit


-- 
Kit BLAKE · Infrae · http://infrae.com/ + 31 10 243 7051