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Hi Jill,

I did a CONTENTdm to Omeka migration many years back. Wilhelmina pretty
much covered what you need to be thinking about, but first thing to know is
that OAI is rarely an appropriate migration tool. The second is that the
whole point of migrating is that the new system works differently than the
old one -- i.e. you need to migrate an effect and set yourself up for the
future. This can be very different than faithfully moving everything over
intact.

OAI limits you to very specific types of metadata -- if you look at the
fields, you're going to find a lot in your CONTENTdm records isn't
represented at all. You'll probably also notice that your suppressed
records aren't visible, permissions, etc.

Hopefully they've fixed this by now, but the native export in CONTENTdm
spit out invalid XML at the time I did it and had some really annoying
bugs. For example, every heading in a repeatable field that contained an
XML entity (e.g. "&") then got split on the semicolon messing up the field
and the entity. For example,

<subject>Dogs & cats</subject>
was exported as
<subject>Dogs &amp</subject>
<subject>cats</subject>

There were also invalid characters, and I remember the csv export having
quoting problems, line breaks in records, and the like. Binary objects
associated with the metadata was also fairly clunky and made more
complicated by access controls.

Regarding the cpd structure -- how you parse that really depends on what
the object is and how you want to represent it in the new system which
could be very different. Your specific example looks like an automatically
generated index to jpg images for printed material which may or may not be
usable as a structure in your new system -- you may well find it easier to
just ingest the who thing as a singular file or do something else.

kyle

On Mon, Sep 13, 2021 at 8:48 AM Jill Ellern <[log in to unmask]> wrote:

> Well that make sense!   Is there folks out there that have converted from
> CONTENTdm to other systems? (Dspace?, others?...)  How did you get the
> structure info from the cpd files to populate the new system?
> Jill
>
> -----Original Message-----
> From: Code for Libraries <[log in to unmask]> On Behalf Of Brian
> Meuse
> Sent: Monday, September 13, 2021 11:31 AM
> To: [log in to unmask]
> Subject: Re: [CODE4LIB] Do we have any OAI programmers here? I have
> questions.
>
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>
> WARNING: This email originated from a non-WCU email account. Do not click
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>
> Hi,
>
> For what it's worth, OAI is usually meant to harvest descriptive metadata,
> not structural. DPLA doesn't host content, AFAIK, they just link back to
> the host site.
>
>
> On Mon, Sep 13, 2021 at 11:00 AM Jill Ellern <[log in to unmask]> wrote:
>
> > Code4lib folks,
> > Thanks to everyone for help on this...It has kept me up last night
> > thinking about...  It certainly seemed like it from the documentation
> > at
> > https://help.oclc.org/Metadata_Services/CONTENTdm/CONTENTdm_Administra
> > tion/Collection_administration/090Export_metadata
> >
> >
> > So I was hoping that the data structure info was in either the OAI and
> > then it occurred to me that it might also be in the XML data. (it
> > looks like it from the brief info in the documentation) So I had a
> > long conversation with OCLC/ContentDm.
> > I was disappointed to I found out that the "structure" of the compound
> > images (also called the containers for those in Contentdm) that might
> > have multiple children files is in files called #.cpd.  Those files
> > are kept in the images folder.  The data looks like this <?xml
> > version="1.0" encoding="utf-8"?> <cpd>
> >   <type>Document</type>
> >   <page>
> >     <pagetitle>Page 1</pagetitle>
> >     <pagefile>253.jpg</pagefile>
> >     <pageptr>252</pageptr>
> >   </page>
> >   <page>
> >     <pagetitle>Pages 2 &amp; 3</pagetitle>
> >     <pagefile>254.jpg</pagefile>
> >     <pageptr>253</pageptr>
> >   </page>
> >   <page>
> >     <pagetitle>Page 4</pagetitle>
> >     <pagefile>255.jpg</pagefile>
> >     <pageptr>254</pageptr>
> >   </page>
> > </cpd>
> >
> > I'm wondering how places like OCLC and DLA actually harvest the data
> > from CONTENTdm OAI without these files.
> >
> > Jill
> >
> > > On Sep 13, 2021, at 4:07 AM, Jill Ellern <[log in to unmask]> wrote:
> > >
> > > Code4lib folks,
> > >
> > > I have perhaps some stupid OAI questions.  We are moving off
> > > Contentdm
> > and onto a platform with programmers that I’m pretty sure don't know
> > OAI and harvesting at all.  We  have been thinking that it would be
> > simple to convert our output of metadata that comes in a text format.
> > However, we see now that it drops the set structure (front and back of
> > an image for
> > example) especially since we have some collections that have different
> > titles for the container (root description) and the images attached.
> > We do see a line with cpd but with different titles, it look like we
> > might have to identify sets in Excel.  That sounds like a big job and
> > a pain.  I'm thinking there is a better way with OAI but I don't know
> much about it.
> > > My thinking is that we can use OAI to move this data instead of text
> > files.  I'm sure it has the structure built in...doesn't it?  Is there
> > a easy tutorial on OAI?  I’m not finding much for the layperson. And
> > our new vendor is pretty new to library land (they are in museum land)
> > and we doubt if they know OAI and I don't see easy ways to teach them.
> > Do you have suggestions?
> > >
> > > Jill Ellern
> > >
> >
>
>
> --
> Brian Meuse, MSLIS
> he/him/his
>
> Digital Initiatives Librarian
> Brandeis University Library
>
> *Proud member of SEIU Local 888*
>