[Bug 1132] - fix access control rule ambiguities

[bugzilla-daemon@ecoinformatics.org]

http://bugzilla.ecoinformatics.org/show_bug.cgi?id=1132

sgarg at nceas.ucsb.edu changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|EML2.0.2                    |EML2.1.0



------- Additional Comments From sgarg at nceas.ucsb.edu  2004-05-10 15:22 -------

Notes taken based on the conversation on 6th May 2004:

1. Discussion on how Access should be handled in Metacat while reading eml 2.0.0
In eml 2.0.0 Access can be specified in following places.
//eml/dataset/access
//eml/citation/access
//eml/software/access
//eml/protocol/access
//eml/additionalMetadata

Permissions in //eml/dataset/access will be applied to all the metadata and by 
default to the data. Any permissions specified in //eml/citation/access, 
//eml/software/access and //eml/protocol/access are ignored. So all the 
metadata has same permissions overall. However, access rules can still be 
specified for any data attached to the metadata. This can be done in following 
manner:
Define a reference id in the <distribution> for which you want to define the 
access control. e.g. 
        <distribution id="xxyyzz">
                .
                .
        </distribution>
To define the access rule for the above distribution, use
//eml/additionalMetadata is following way:
<additionalMetadata>
     <describes>
        xxyyzz
     </describes>
     <access>
          .
          .
     <access>
</additionalMetadata>

If additioncalMetadata describes as id which is not defined in the current eml 
document, then that additioncalMetadata is ignored. 
If the id is defined in the current eml document, but is not in distribution 
tag, then also that additioncalMetadata is ignored. 
If a distribution tag contains reference id but there is no additional Metadata 
entry for that reference id, then the rules specified in //eml/dataset/access 
are applied to this distribution. 

2. Discussion on how Access should be handled in Metacat while reading eml 2.1.0
In eml 2.1.0 Access can be specified in following places.
//eml/access
//eml/..../distribution/access

Permissions in //eml/access will be applied to all the metadata and by default 
to the data. So all the metadata has same permissions overall. However, access 
rules can still be specified for any data attached to the metadata. This can be 
done using the /access that will now be added to the distribution tag. e.g. 
        <distribution>
           <access>
              .
           <access>
        </distribution>

If no access is specified in distribution then //eml/access rules are applied.