Claims are GPG signed XML documents which contain claim-set root elements. An example claim-set may be:
<?xml version="1.0" encoding="UTF-8"?>
<claim-set
xmlns="https://evr.ma300k.de/claims/"
xmlns:dc="http://purl.org/dc/terms/"
dc:created="2022-04-23T16:32:07.000000Z"
>
<some-claim xmlns="https://my.claim.ns">
This is the pice of fact we would like to store.
</some-claim>
</claim-set>
A claim-set contains claims. everarch comes with a limited set of supported claims. These include for example an attr claim which can define attributes for itself or another seed claim.
Just like blobs claims also have references. A claim reference is the blob reference which contains the claim-set concatinated with the index of the claim in the claim-set. The index is encoded in hexadecimal form. A claim reference might be sha3-224-00000000000000000000000000000000000000000000000000000000-0000.
The following attr claim defines some attribute changes for a referenced seed claim which was created in the past.
<attr
xmlns="https://evr.ma300k.de/claims/"
seed="sha3-224-00000000000000000000000000000000000000000000000000000000-0000">
<!-- adds the value v to the set of tag values -->
<a op="+" k="tag" v="todo"/>
<!-- empties the set of values for someKey -->
<a op="-" k="someKey"/>
<!-- removes the value v from the set of values for someKey -->
<a op="-" k="someKey" v="someVal"/>
<!-- replaces the set of values for replacedKey with replacedVal -->
<a op="=" k="replacedKey" v="replacedVal"/>
</attr>
As you can see in the example you should be able to easily add your own self defined claims. In order to make them searchable you must provide an XSLT stylesheet which converts your claim into attr claims.
The archive claim is beside the attr claims another built in claim type. Archive claims are used to indicate that a seed is archived at a certain point in time and should not be shown in future searches.
Archive claims may look like this:
<archive
xmlns="https://evr.ma300k.de/claims/"
seed="sha3-224-00000000000000000000000000000000000000000000000000000000-0000"
/>