[Building Sakai] Entity References Broken During Site Import: Solution Vote (KNL-737 or SAK-16568)

[Matthew Buckett]

On Thu, Jul 28, 2011 at 2:07 PM, Bryan Holladay <holladay at longsight.com> wrote:
> Matt can describe his and maybe we can make an educated decision here?

Background:

Most tools at the moment support the transfer of content from one site
to another. When they do this however they don't update any of the
content, so if you have a link to a PDF held in the current site's
resource in the syllabus, when the syllabus is transferred to the new
site the link remains pointing to the old site, if people don't have
access to the old site they aren't able to access the PDF.

Solution:

So what both Bryan and I have done it have the tools re-write their
content when they are transferring it from one site to another. What I
did was provide a service that allows tools to have each piece of
their content scanned for links and those links re-written and the
content handed back to the tool. I also build list of resources that
the content linked to and all the resources needed by that resource
which can be automatically copied. This is so that if you are just
importing the syllabus from another site you get a copy of the
syllabus (with the links updated) in your new site but also any
references to content in resources will be copied across even if you
don't want the whole of the resources tool copied.

The new service supports looking at HTML and plain text for references
to content in resources. I have patches for all the core tools to
support this, they are currently against 2.6.x but we are moving to
2.8.x over the summary so I will need to update them to close to
trunk.

I do full regexp replaces in content only if the context IDs (site
IDs) are auto-generated so that if you allow custom site IDs we don't
accidentally re-write content we shouldn't.

I like the service solution as it means we don't end up with this
logic duplicated across lots of tools.

Issues:

I don't scan the content for links to things other than resources. So
for example, if you have a HTML file in resources which links to a
forums discussion topic, and you are only copying the resources of a
site, I won't automatically add the Forum to the destination site and
create a copy of the referenced discussion topic. With our current URL
management I don't think this would be easy todo.

Side note: I'm off on holiday (for 10 days yey) in about 2 hours and
will be away from email, so I'm not ignoring responses.

  Matthew Buckett
  VLE Developer, LTG, Oxford University Computing Services