[eml-dev] EML access and application behavior (metacat)

[Margaret O'Brien]

Hi Inigo -
Since we went to EML 2.1.0, that opened the door for other 
backward-incompatible changes. One that was always targeted for 2.1 was 
to clean up the access rules. See bug 1132 
(http://bugzilla.ecoinformatics.org/show_bug.cgi?id=1132).

In EML 2.0.1 datasets, access to the metadata was controlled at 
eml/dataset/access, and for control of other nodes, authors were told to 
add additonalMetadata sections with access trees and <describes> 
elements pointing to the node they wanted the rules to apply to. But in 
reality, node-level access control is too problematic to implement. So 
the best solution is to identify the document parts that people most 
want to control over, and put access trees where their rules can be 
applied to those parts.

The 2 places where authors most often want  to control access are on the 
entire metadata document, and the individual entities it describes. This 
required 2 changes to EML 2.1:
1. to make it clear that an access tree controlled the entire package, 
<access> will be a sibling of dataset rather than a child.
2. an access tree was added to the PhysicalDistributionType by extension 
(see bug 3480 for that discussion, and my questions about the use of the 
distribution tree)

So, the upshot for EML-2.1.0
<access>  will appear in these locations:
eml/access
eml/dataset/dataTable/distribution/physical/access

See bugzilla for examples. And the documentation will state that 
node-level access control is not reasonable. So while it is possible to 
put an access tree into an additionalMetadata section, it's not 
recommended, and authors shouldn't expect them to be recognized by 
applications like metacat. 

I havent thought much about the 201-to-210 xslt stylesheet yet, but I 
think it should be able to handle moving the access trees around.

Margaret
===================



inigo wrote:
>
> Dear Margaret,
>
> There is no <access> under <distribution>, isn't it? I think you meant 
> under the main resource in (i.e;) <dataset>
> /eml/dataset/access
>
> cheers, inigo
> Margaret O'Brien wrote:
>> EML2.0.1: yes, what I was hoping.
>> EML2.1.0: I agree that recognizing access trees in additionalMetadata 
>> is unnecessary. That's what I prefer - people should use <access> 
>> under <distribution>, and discontinue putting it in addionalMetadata 
>> altogether.
>>
>> life is simpler. thanks!
>> margaret
>>
>> Jing Tao wrote:
>>> Hi, Margaret:
>>>
>>> See my comments under the text.
>>>
>>> Thanks,
>>>
>>> Jing
>>>
>>> Jing Tao
>>> National Center for Ecological
>>> Analysis and Synthesis (NCEAS)
>>> 735 State St. Suite 204
>>> Santa Barbara, CA 93101
>>>
>>> On Wed, 17 Sep 2008, Margaret O'Brien wrote:
>>>
>>>> Hi Jing -
>>>> I am updating the EML documentation for access. Per our discussion 
>>>> last week, I just wanted to confirm the planned behavior of metacat 
>>>> with regard to access trees in EML.
>>>>
>>>> 1. in EML 2.0.1, access is located at eml/dataset/access, and 
>>>> authors may also have been putting in additionalMetadata/access as 
>>>> well, accompanied by <describes>any_node_id</describes>
>>>> And you plan that metacat will
>>>> a. honor the eml/dataset/access tree (for all metadata and data) and
>>>> b. when it finds an access tree in an additionMetadata section, it 
>>>> will recognize it only if it references an id on a distribution 
>>>> element that is a descendant of dataTable  -- or is it honoring a 
>>>> reference to any distribution id (ie, res:distribution).
>>>>
>>> Metacat currently is doing the way you described (maybe a little 
>>> different).
>>> If no additionalMetadata/access in eml, the eml/dataset/access will 
>>> be applied to EML document itself(metadata) and all data files.
>>>
>>> If there is additionalMetadata/access in eml and the id in element 
>>> <describes> references a distribution element that is a descendant 
>>> of dataTable (or other entities), the rules of 
>>> additionalMetadata/access will be applied to the data table. The 
>>> eml/dataset/access will be applied to EML document itself and other 
>>> data files (if there is any) which are not in the <describes> in 
>>> <additionalMetadata>.
>>>
>>>> 2. in EML 2.1.0, access will be found at eml/access and 
>>>> /eml/dataset/dataTable/distribution/physical/access
>>>> And metacat will
>>>> a. continue to honor eml/access for all metadata and data, and
>>>> b. not recognize access trees found under additionalMetadata. Does 
>>>> that mean it will ignore additionalMetadata/metadata/access trees 
>>>> that were honored in 2.0.1, or can EML authors continue to create 
>>>> these?
>>>>
>>> In the eml 2.1.0, my guess 
>>> /eml/dataset/dataTable/distribution/physical/access is the 
>>> replacement of additionalMetadata/access in eml 2.0.1. So there is 
>>> no reason to continue to use additionalMetadata/access to controll 
>>> the access of the data files in eml 2.1.0. So i think metacat can 
>>> ingore additionalMetadata/metadata/access
>>> trees in eml 2.1.0 documents. What do you think?
>>>
>>>> thanks -
>>>> Margaret
>>>>
>>>> -- 
>>>>
>>>>
>>>> ========================
>>>> Margaret O'Brien
>>>> Information Management
>>>> Santa Barbara Coastal LTER Marine Science Institute
>>>> University of California
>>>> Santa Barbara, CA  93106-6150
>>>>
>>>> 805-893-2071
>>>> mob at icess.ucsb.edu
>>>> http://sbc.lternet.edu
>>>> ========================
>>>>
>>>>
>>>>
>>
>

-- 


========================
Margaret O'Brien
Information Management
Santa Barbara Coastal LTER 
Marine Science Institute
University of California
Santa Barbara, CA  93106-6150

805-893-2071
mob at icess.ucsb.edu
http://sbc.lternet.edu
========================